Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages. Squid has extensive access controls and makes a great server accelerator. It runs on most available operating systems, including Windows and is licensed under the GNU GPL.
Squid optimises the data flow between client and server to improve performance and caches frequently-used content to save bandwidth. Squid can also route content requests to servers in a wide variety of ways to build cache server hierarchies which optimise network throughput.
Thursday, September 10, 2009
Group3_AMAK: Network protocol analysis
In last week's post we had covered the different types of protocols and a brief insight into what is network protocol analysis. Also covered was the various network protocol analyzers or packet sniffers commonly used. This week we will be learning more on network protocol analysis. In the typical network architecture, a layered approach is used to design network protocols and communications. The most popular network architecture reference model is called the OSI model. The protocols at one layer should communicate with protocols at the same layer. Each of the seven layers of the protocol stack have specific protocols through which they communicate. The key function of a protocol analyzer is to decode the protocol at each layer. Network protocol analyzers or packet sniffers are used to analyze the network protocols. These capture the data passing through your dial-up connection or network Ethernet card, analyze this data and then represents it in an easily readable form. Analyzers defragment and reassemble network packets into streams which now become the readable form.
The packet analyzers consist of a flexible system of fully configurable filters can be used to discard all network traffic except the specific traffic patterns you wish to analyze. Like for example we can filter the FTP protocol and allow TCP/IP protocols. Protocol Analyzers can be used both for legitimate network management or for stealing information off a network. Network operations and maintenance personnel use Protocol Analyzer to monitor network traffic, analyze packets, watch network resource utilization, conduct forensic analysis of network security breaches and troubleshoot network problems. Unauthorized protocol analyzers can be extremely dangerous to a network's security because they are virtually impossible to detect and can be inserted almost anywhere. This makes them a favorite weapon of hackers as they can reassemble the data transmitted in a network back in readable form hence information exchanged on the network can easily be viewed and hence pose a threat.
group17_the spark:introduction to FTP
INTRODUCTION ABOUT FTP(File Transfer Protocol).
FILE TRANSFER.
Transferring files from one system to another system is one of the biggest tasks in the networking environment.the large volume of data transfer in the internet today is due to the file transfer and the protocol that is responsible for this task of file transferring is File Transfer Protocol.
File transfer protocol is the standard mechanism provided by TCP\IP for copying and transferring the file from one host to another which seems to be simple and straightforward. FTP differs from other client server applications since it establishes 2 connections between hosts.
That is one connection for data transfer and other for control information.This separation of data and commands makes ftp more efficient.Control connection uses very simple rules for communications where only one command or data is transferred at a time.in data connection since it need to transfer different data types uses a bit complex procedure.
FTP uses two well known TCP ports:
PORT 21 is used for the control connection.
PORT 20 is used for data connection.
COMMUNICATION OVER CONTROL CONNECTION.
FTP uses same approach as SMPT to communicate by using 7 bit ASCII character which is very simple .Each command or response is only one short line and hence need not worry about the file format and file structure.
COMMUNICATION OVER DATA CONNECTION.
File transfer occurs over data connection under control of some set of commands which is sent over control connection.
File transfer in FTP means one of the three things i.e.
Retrieving the file -command used is RETR .
Storing a file-command used is STOR.
Listing of files or directories-command used is LIST .
The client has to define type of file ,data structure and transmission mode.
FILE TRANSFER.
Transferring files from one system to another system is one of the biggest tasks in the networking environment.the large volume of data transfer in the internet today is due to the file transfer and the protocol that is responsible for this task of file transferring is File Transfer Protocol.
File transfer protocol is the standard mechanism provided by TCP\IP for copying and transferring the file from one host to another which seems to be simple and straightforward. FTP differs from other client server applications since it establishes 2 connections between hosts.
That is one connection for data transfer and other for control information.This separation of data and commands makes ftp more efficient.Control connection uses very simple rules for communications where only one command or data is transferred at a time.in data connection since it need to transfer different data types uses a bit complex procedure.
FTP uses two well known TCP ports:
PORT 21 is used for the control connection.
PORT 20 is used for data connection.
COMMUNICATION OVER CONTROL CONNECTION.
FTP uses same approach as SMPT to communicate by using 7 bit ASCII character which is very simple .Each command or response is only one short line and hence need not worry about the file format and file structure.
COMMUNICATION OVER DATA CONNECTION.
File transfer occurs over data connection under control of some set of commands which is sent over control connection.
File transfer in FTP means one of the three things i.e.
Retrieving the file -command used is RETR .
Storing a file-command used is STOR.
Listing of files or directories-command used is LIST .
The client has to define type of file ,data structure and transmission mode.
- File type includes ASCII FILE,EBCDIC file,IMAGE file.
- Data structure includes file structure,record structure and page structure.
- Transmission mode includes stream mode,block mode and compressed mode.
group17_the spark:http proxy server.
PROXY SERVER
A proxy server is a server that acts as an intermediary between a workstation user and the Internet so that the enterprise can ensure security, administrative control, and caching service.
Proxy servers have two main purposes:
Improve Performance: Proxy servers can improve performance for groups of users. This is because it saves the results of all requests for a certain amount of time. Consider the case where both user X and user Y access the World Wide Web through a proxy server. First user X requests a certain Web page, which we'll call Page 1. Sometime later, user Y requests the same page. Instead of forwarding the request to the Web server where Page 1 resides, which can be a time-consuming operation, the proxy server simply returns the Page 1 that it already fetched for user X,hence this is a much faster operation. Real proxy servers support hundreds or thousands of users. The major online services such as America Online, MSN and Yahoo, for example, employ an array of proxy servers.
Filter Requests: Proxy servers can also be used to filter requests. For example, a company might use a proxy server to prevent its employees from accessing a specific set of Web sites.it may also commmunicate to daemon based or ICAP based anti virus software to provide security against virus and other malware by scanning incoming content in real time before it enters the network.
The HYPERTEXT TRANSFER PROTOCOL is used mainly to access data on the world wide web . the protocol tranfers datd in the form of plain text, hypertext , audio, video and so on. It is called the hypertext transfer protocol because it is used in an envirornment where there are rapid jumps from one document to another.During the HTTP connection,the IP address of the client machine is necessarily transmitted in order to get the information back. This allows a server to identify the source of the web request.
HTTP proxy servers interprets web access.
HTTP is a proxy server which acts as an middleman between your web browser and an end server.Instead of directly connecting to web page it connects to the proxy which forwards the request to end server. They support many programms browsers, download managers. They can be united into a chain and in a chain can be mixed with other types of proxy servers like SOCKS and CGI.
A proxy server is a server that acts as an intermediary between a workstation user and the Internet so that the enterprise can ensure security, administrative control, and caching service.
Proxy servers have two main purposes:
Improve Performance: Proxy servers can improve performance for groups of users. This is because it saves the results of all requests for a certain amount of time. Consider the case where both user X and user Y access the World Wide Web through a proxy server. First user X requests a certain Web page, which we'll call Page 1. Sometime later, user Y requests the same page. Instead of forwarding the request to the Web server where Page 1 resides, which can be a time-consuming operation, the proxy server simply returns the Page 1 that it already fetched for user X,hence this is a much faster operation. Real proxy servers support hundreds or thousands of users. The major online services such as America Online, MSN and Yahoo, for example, employ an array of proxy servers.
Filter Requests: Proxy servers can also be used to filter requests. For example, a company might use a proxy server to prevent its employees from accessing a specific set of Web sites.it may also commmunicate to daemon based or ICAP based anti virus software to provide security against virus and other malware by scanning incoming content in real time before it enters the network.
The HYPERTEXT TRANSFER PROTOCOL is used mainly to access data on the world wide web . the protocol tranfers datd in the form of plain text, hypertext , audio, video and so on. It is called the hypertext transfer protocol because it is used in an envirornment where there are rapid jumps from one document to another.During the HTTP connection,the IP address of the client machine is necessarily transmitted in order to get the information back. This allows a server to identify the source of the web request.
HTTP proxy servers interprets web access.
HTTP is a proxy server which acts as an middleman between your web browser and an end server.Instead of directly connecting to web page it connects to the proxy which forwards the request to end server. They support many programms browsers, download managers. They can be united into a chain and in a chain can be mixed with other types of proxy servers like SOCKS and CGI.
group17_the spark:understanding of computer networks
Computer network is a collection of several autonomous computers interconnected by a single technology .
Resource sharing and communication are the two principle reasons of building and using computer networks.
Some of the most popular applications include email, web browser, digital libraries, video -on-demand, file transfer, video or audio conferencing, e-commerce, etc.
Computers in a network are interconnected through a transmission media through which the data can be shared.
Transmission media are classified into wire based and wireless media.
- Computer networks use a well defined mutually agreed set of rules and conventions known as protocols.
- They interact with one another who are authenticated and authorized.
- They allow source sharing preferabally in a predictable and controllable manner.
Resource sharing and communication are the two principle reasons of building and using computer networks.
Some of the most popular applications include email, web browser, digital libraries, video -on-demand, file transfer, video or audio conferencing, e-commerce, etc.
Computers in a network are interconnected through a transmission media through which the data can be shared.
Transmission media are classified into wire based and wireless media.
- Wired media includes fiber optic cables, twisted pair cable, coaxial cable etc
- wireless media includes bluetooth, infrared, terrestrial microwaves, communication satellites, cellular and pcs systems, wireless LANs etc
- In client-server computing, computer plays a major role known as server where the files, data in the form of web pages, documents, data base and resources are placed and the computers in this network are called clients and they receive data from the server.
- In peer-peer networks, all the computers play the same role and no computer acts as a centralised server.
Wednesday, September 9, 2009
group15_krazzy4:first weekly report on REMOTE LOGIN
In this post we are actually going to see how things work in remote login. For this consider two parties i> A host computer and
ii>A remote user.
The host computer is the computer that is to be accessed by a user who is remote to that system. When we relate to our prvious example the host computer is the computer that is placed in the cluster lab and 'X' is the remote user.
For remote login to work successfully three major components are required viz : A common software(eg team viewer),an internet connection and a secure desktop sharing network. The common software consists of two distinct programs which are :
1)The desktop sharing client that runs on the host computer and
2)A viewer program that allows the remote user to view the contents of the host.
The scheme works when both the host and the remote user are connected to the net and both use the same desktop sharing software. We have tried doing this using the Team Viewer software on the windows vista operating software. Through this software the host computer was able to hand over it's keyboard and mouse controls to the remote user. In order to do this the software must be run on the host computer first where it generates a partner id and password. In order for the remote user to access the host computer, it has to request the host computer for the partner id and the password. Thus we were able to control the host computer through a common software when both the host and the remote systems were connected to the internet.
Group18_Awesome4some: HTTP/FTP Proxy servers (introduction)
Proxy servers:
A proxy server is a server (a machine or a program) which is present between the user (client side) and the Internet. When a person requests for a particular web page, the request is passed on directly to the server and the requested page is located, retrieved and sent back to the requested computer. This is done by locating the surfer’s IP address, and then transferring back to the same IP address which had requested the web page. But with the introduction of proxy servers the request is intercepted by it and the request does not reach the real server. The proxy server acts as a regular server by saving caches of all previously downloaded websites. When a request sent to server is intercepted by the proxy server, it checks in its cache. If the page is found then it is sent back to the Ip which raised the request. If it is not found then, the proxy uses its own IP address and raises a request to the real server and then sends it to the requested terminal. This is useful in terms of retaining anonymity, to speed up the process of webpage retrieval and to filter requests. There are many types of Proxy servers like transparent proxy, anonymous proxy, distorting proxy, high anonymity proxy.
Http proxy server:
Hypertext Transfer Protocol (HTTP) is an application-level protocol used for retrieving inter-linked resources led to the establishment of the World Wide Web. HTTP is a request/response standard of a client (end user) and a server (web site). The client making an HTTP request—using a web browser, etc—is referred to as the user agent. The responding server—which stores or creates resources such as HTML files and images—is called the origin server.
HTTP proxy server is a proxy, allowing working on the Internet with HTTP and (not always) FTP protocols. It (as well as other proxy servers) can carry out caching of information downloaded from the Internet. HTTP proxy servers are the most prominently used.
Ftp Proxy server:
File Transfer Protocol (FTP) is a standard network protocol used to exchange and manipulate files over an Internet. FTP is also built on a client-server architecture and utilizes separate control and data connections between the client and server applications. FTP is also often used as an application component to automatically transfer files for program internal functions and can be used with user-based password authentication or with anonymous user access.
Ftp proxy is an application level gateway for FTP. It sits between a client and a server forwarding command and data streams supporting a subset of the file transfer protocol as described in RFC 959. Beside this basic function which makes the program useful on firewall or masqueraders it offers fixing the FTP server (e.g. for connections into a protected LAN) and proxy authentication.
Group11_dnaa:Protocol Stack and Addressing
International Standards Organization (ISO) developed OSI model as a first step towards international standardization of the protocols used in the various layers. The model is known as the ISO OSI Reference Model because it is related with connecting open system i.e. systems that are open for communication with other systems.
The OSI model includes seven layers:
A layer is a collection of conceptually similar functions that provide services to the layer above it and receives service from the layer below it. On each layer an instance provides services to the instances at the layer above and requests service from the layer below. For example, a layer that provides error-free communications across a network provides the path needed by applications above it, while it calls the next lower layer to send and receive packets that make up the contents of the path. Conceptually two instances at one layer are connected by a horizontal protocol connection on that layer.
Different layers of ISO OSI model are as follows:
1) Physical Layer describes the physical & electrical properties of the communications media.
e.g., voltage levels, data rates, max distances.
2) Data Link layer describes the logical organization of data bits transmitted on a particular
medium.
e.g., frame sequencing, error notification
3) Network Layer describes how a series of exchanges over various data links can deliver data across a network.
e.g., addressing and routing
4) Transport Layer describes the quality and nature of data delivery
e.g., how retransmissions are used to ensure delivery
5) Session layer describes the organization of large data sequences & manages
communication session.
e.g., coordinates requests/responses
6) Presentation Layer describes the form of data being transferred & ensures that it will be
readable by receiver.
e.g., floating point formats, data compression, encryption
7) Application Layer describes how applications will communicate
e.g., HTTP, FTP, Telnet, SMTP
Physical layer:
The physical layer defines the hardware implementation, mechanical, electrical and procedural interfaces and the physical communication channel which lies below the physical layer. At this layer information is placed on the physical medium. The Physical Layer will tell one device how to transmit to the medium, and another device how to receive from it. It is related with delivering raw bits over a communication channel. The design issues have to do with making sure that when one side sends a 1 bit, it is received as a 1 bit by the other side but not as a 0 bit. The physical layer performs services requested by the Data Link Layer.
The major functions and services performed by the Physical Layer:
- Definition of Hardware Specifications: The details of operation of cables, connectors wireless radio transceivers, network interface cards and other hardware devices are generally a function of the physical layer.
- Physical topology: establishment and termination of a connection to a communications media. It defines how devices are connected to devices to media. Devices can be connected by using mesh topology, star topology, ring topology or bus topology.
- Participation in the process whereby the communication resources are effectively shared among multiple users.
- Representation of bits: Conversion between the representation of digital data in user equipment and the corresponding signals transmitted over a communications channel. To be transmitted bits must be encoded into signals electrical or optical.
- Encoding and Signaling: The physical layer data consists of a stream of bits with no interpretation thus it is responsible for various encoding and signaling functions that transform the data from bits that reside within a computer or other device into signals that can be sent over the network.
- Date transmission rate: The transmission rate the no of bits sent each second is also defined by the physical layer.
- Transmission mode: The physical layer also defines the direction of transmission between two devices:simplex,half dupolex,full duplex.
Group1_Charisma:First weekly report of the project network protocol analysis
Our objective in the previous week was to understand the basics of network protocol analysis, know more about the tools used and thier working,and we have accomplished the same.We have learnt that network protocol analysis is a process of decoding packets of information encapsulated by the protocol.This can be done using a network protocol analyser which can also be used to build protocols.In the typical network architecture, a layered approach is used to design network protocols and communications. The most popular network architecture reference model is called the OSI model. The protocols at one layer should communicate with protocols at the same layer.The regular computer communication class was of great help in making us understand these concepts better and get a vivid picture of how protocol stack works. The key function of a protocol analyzer is to decode the protocol at each layer. Protocol information of multiple layers may be used by protocol analyzer to identify possible problems in the network communication, which is called Expert Analysis.
With this background we learnt about the usage of the protocol analyser tool wireshark.These are some of the commands whose syntaxes and functions were understood by us:-
capinfos - Prints information about capture files
dumpcap - Dump network traffic
editcap - Edit and/or translate the format of capture files
idl2wrs - CORBA IDL to Wireshark Plugin Generator
mergecap - Merges two or more capture files into one
rawshark - Dump and analyze raw libpcap data
text2pcap - Generate a capture file from an ASCII hexdump of packets
tshark - Dump and analyze network traffic
wireshark-filter - Wireshark filter syntax and reference
wireshark - Interactively dump and analyze network traffic
We look forward to learn more about wireshark by next week.
With this background we learnt about the usage of the protocol analyser tool wireshark.These are some of the commands whose syntaxes and functions were understood by us:-
capinfos - Prints information about capture files
dumpcap - Dump network traffic
editcap - Edit and/or translate the format of capture files
idl2wrs - CORBA IDL to Wireshark Plugin Generator
mergecap - Merges two or more capture files into one
rawshark - Dump and analyze raw libpcap data
text2pcap - Generate a capture file from an ASCII hexdump of packets
tshark - Dump and analyze network traffic
wireshark-filter - Wireshark filter syntax and reference
wireshark - Interactively dump and analyze network traffic
We look forward to learn more about wireshark by next week.
group9_dead lock:Transmission control protocol
TCP is one of the main protocols in TCP/IP networks. TCP/IP was developed in the 1970s and adopted as the protocol standard for ARPANET (the predecessor to the Internet) in 1983.Whereas the IP protocol deals only with packets. TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent.It is a popular network debugging tool used to intercept and display packets transmitted or received on a network.TCPdump is one of those tools that network and systems administrators alike reach for whenever they need to take a look at the actual network packets. The TCP/IP suite provides two transport methods and also ensures that data arrive intact and complete. It is used for everything that must arrive in perfect form.
The TCP transport layer 4 sends packets to IP network layer 3, which adds its own header and delivers a "datagram" to a data link layer 2 protocol such as Ethernet, ATM or SONET. Datagram is the unit of data or packet, transmitted in a TCP/IP network. Each datagram contains source and destination addresses and data.
group14_indigo:this week report of remote login
For using the TELNET command for remote login the syntax is:
-->telnet host name
After connecting with the remote host, you will be prompted for your login id and your password just as if you were logging on via a terminal on that system.
-->telnet host name
After connecting with the remote host, you will be prompted for your login id and your password just as if you were logging on via a terminal on that system.
For using the RLOGIN command for remote login the syntax is:
-->rlogin hostname
This command provides an advantage over the telnet command that is here in this command you can specify a username on the command line, ahttp://www.blogger.com/post-create.g?blogID=1013281640107267804nd can set it up so that when you rlogin to a host you will not be prompted for a password. Rlogin assumes you wish to login to an account with the same name as the account you are presently logged in as. If you wish to change this, use the -l option.
Rlogin: Remote Login in UNIX systems
rlogin (remote login) is a UNIX command that allows an authorized user to login to other UNIX machines (hosts) on a network and to interact as if the user were physically at the host computer. Once logged in to the host, the user can do anything that the host has given permission for, such as read, edit, or delete files.
Each remote machine may have a file named /etc/hosts.equiv containing a list of trusted hostnames with which it shares usernames. Users with the same username on both the local and remote machine may rlogin from the machines listed in the remote machine's /etc/hosts.equiv file without supplying a password. Individual users may set up a similar private equivalence list with the file .rhosts in their home directories. Each line in this file contains two names: a host- name and a username separated by a space. An entry in a remote user's .rhosts file permits the user named username who is logged into hostname to log in to the remote machine as the remote user without supplying a password. If the name of the local host is not found in the /etc/hosts.equiv file on the remote machine, and the local username and hostname are not found in the remote user's .rhosts file, then the remote machine will prompt for a password. Hostnames listed in /etc/hosts.equiv and .rhosts files must be the official hostnames listed in the hosts database; nicknames may not be used in either of these files. For security reasons, the .rhosts file must be owned by either the remote user or by root.
The remote terminal type is the same as your local terminal type (as given in your environment TERM variable). The terminal or window size is also copied to the remote system if the server supports the option, and changes in size are reflected as well. All echoing takes place at the remote site, so that (except for delays) the remote login is transparent. Flow control using
A secure version of rlogin (slogin) was combined with two other UNIX utility, ssh and scp, in the Secure Shell suite, an interface and protocol created to replace the earlier utilities.
group13_Avani:description of protocol stack
Brief description of layers of the OSI model
7. Application layer:
- it is the top layer of the OSI model.
- it is responsible for providing services to the user.
- provides a set of interfaces for sending and receiving applications to gain access to and use network services.
6. Presentation layer
- it converts the data into a generic format for network transmission for outgoing messages and for incoming messages, it converts the data from the generic network format to a format that the receiving application can understand.
- it is also responsible for certain protocol conversions, data encryption/decryption or data compression and decompression.
5. Session layer
- it manages user sessions and dialogues.
- controls establishment and termination of logic links between users.
- reports upper layer errors.
- it is also responsible for security and access control to session information(via session participant identification).
4. Transport layer
- it is responsible for the delivery of a message from one procees to another.
- manages the data flow between parties by segmenting long data streams into smaller data chunks.
- reaasembles chunks into their original sequence at the receiving end.
- provides acknowledgements for successful transmissions and requests resends for packets which arrive with errors.
3. Network layer
- it determines how data is transferred between network devices.
- routes packets according to unique network device addresses.
- provides flow and congestion control to prevent network resource depletion.
2. Data link layer
- handles special data frames(packets) between the network layer and physical layer.
- at the receiving end, it packs the raw data from the physical layer into data frames for delivery to the network layer.
- at the sending end this layer handles conversion of data into raw formats that can be handled by the physical layer.
1. Physical layer
- it is the bottom layer of the OSI model.
- converts bits into electronic signals for outgoing messages and converts electronic signals into bits for incoming messages.
- it manages the interface between the network medium(coax, twisted pair etc) and computer.
Group20_dynamic networks:htp/ftp proxy servers
Now let us be familiar with certain terms used now and then,HTTP and FTP.Computer Networking involves communicating between the computers.So when we request a web-page a computer 'talks' to a web server through a web browser.They speak a language known as HTTP which stands forHyper Text Transfer Protocol.
For ex:
The browser says:
GET /http/1.0
Host:www.cricketnews.com
The server replies:
http/1.0 200 OK
Content-Type: text/html
{
the body of the page
}
Here we can see how the browser is communicating to the server. First the browser request's(GET /http/1.0) indicating that the browser wants to see the home page of the site and it is using 1.0HTTP protocol.The second line indicates the website of the requested page.In the first line of the server's reply (http/1.0 200 OK),indicates the server is also speaking version 1.0 and the request sent was successful and in the second line it is showing the content or type of data it is.
FTP refers to File Transfer Protocol which is an older protocol for moving files back and forth over the networks i.e actually file transfering and also its not a secured way of choice for senstive data.
Project Schedule
| Date | Group A project | Group B project |
| Sept 9 | Group 5, Group 6, Group 7 | - |
| Sept 16 | Group 11, Group 12, Group 16 | - |
| Sept 23 | Group 13, Group 14, Group 15 | - |
| Sept 30 | Group 17, Group 18 | Group 19 |
| Oct 7 | Group 20, Group 9 | Group 5 |
| Oct 14 | Group 19, Group 8 | Group 17 |
| Oct 21 | Group 10, Group 1 | Group 3 |
| Oct 28 | Group 2, Group 4 | Group 13 |
| Nov 4 | Group 3 | Group 11, Group 18 |
| Nov 11 | - | Group 15, Group 6, Group 10 |
| Nov 18 | - | Group 20, Group 9, Group 1 |
| Nov 25 | - | Group 14, Group 4, Group 8 |
| Dec 2 | - | Group 12, Group 7 |
| Dec 9 | - | Group 2, Group 16 |
Group16_QuadMasters:Remote Login
Remote login requires three basic components:
1. Software download
2. Internet connection
3. Secure desktop sharing network
For remote login to work, both the host computer and all remote users have to download and install the same desktop sharing software. Desktop sharing software typically includes two distinct programs:
1. The desktop sharing client that runs on the host computer
2. A viewer program that allows the remote user to view the contents of the host computer's desktop in a resizable window
1. Software download
2. Internet connection
3. Secure desktop sharing network
For remote login to work, both the host computer and all remote users have to download and install the same desktop sharing software. Desktop sharing software typically includes two distinct programs:
1. The desktop sharing client that runs on the host computer
2. A viewer program that allows the remote user to view the contents of the host computer's desktop in a resizable window
Group8_Vintageboys:TCPdump
As said previously, tcp dump is an analyser tool which displays the packets which flow in a network or an interface in a computer or a server(which analyses the packets which the server is using) and displays them.
It allows us to view entire ethernet frame or other link layer and if required print the frame header. By default, tcp dump prints the packets at the IP layer.
TCPdump generally helps in solving a variety of problems and analysts say that the number of server based problems that could be solved by using TCPdump is limitless since it prints detailed information about network traffic, helps in debug denial and during service attacks. If a network is flooded and all other attempts to determine the source or destination of the traffic fail, tcpdump will show you the source address, destination address, and type of traffic involved.
It allows us to view entire ethernet frame or other link layer and if required print the frame header. By default, tcp dump prints the packets at the IP layer.
TCPdump generally helps in solving a variety of problems and analysts say that the number of server based problems that could be solved by using TCPdump is limitless since it prints detailed information about network traffic, helps in debug denial and during service attacks. If a network is flooded and all other attempts to determine the source or destination of the traffic fail, tcpdump will show you the source address, destination address, and type of traffic involved.
Thursday, September 3, 2009
MKN_Folks...SOS Need Ur help!
Yup! This is "ejjactly" how I felt when I saw your neat little blogs, children, on our CN Blog Site! Why, that mammoth look of frustration? The sheer volume of the number of blogs to read and evaluate!
Thought that the hyperlinks to your blogs will fit in one page, neatly on the left hand side. Each of us faculties need read only a max of 5 blogs of groups we are handling. By the way, saw the blogs on 5 B's Home Page (http://netbrainz.blogspot.com/) ?
Pretty neat...Has a lot of YouTube Videos on some good sensible "fundas" on Networking :-)
Well, to say the least, I think Iam waaaaaaaay too short-sighted as well as did not foresee the avalance of information you folks would collect and post! Maybe under-estimated the energy and enthusiasm inherent in your present chronological age, dear students! I ADMIT :-) Therefore, this blog. I need help, ideas to make it more manageable. Could someone volunteer to help me? I will give admin rights to your gmail id, so you could implement your ideas of helping me. Its SOS considering the amount of blogs that will be logged every lab! Do email me mydhili.nair@gmail.com with any of your ideas, okies? Looking forward to your co-operation, folks!:-)
---Mydhili
Tuesday, September 1, 2009
Group12_chaarMusafirs:how does internet works?
The Internet is a global network of computers that connects millions of people and uses the Internet Protocol Suite (TCP/IP) standard rules for data representation, signaling, authentication, and error detection. Each computer connected to the Internet must have a unique address. Internet addresses are in the form nnn.nnn.nnn.nnn where nnn must be a number from 0 - 255. This address is known as an IP address. Once a laptop or computers is connected to any routers or servers then IP addresses is automatically assigned to them. If we want to access the web server then we take the help of DNS(domain name service)server. If we type www.google.com then it connects to the Google DNS server and match the IP address of searched item and display the searched items on the page.
Group12_ChaarMusafirs : Protocol Stack and addressing
Our project will describe the several protocols in details, and put forth comparisons (for eg. With the OSI reference model) Our goal is to analyze data from a live network or from a capture file on disk, and examine details of the packets transmitted and the protocols used. Our program of choice for the network analysis is Wireshark(formerly ethereal) and N map. We plan to host dummy networks, and transfer files, download torrents, P2P programs and host game servers which will be then be monitored by these tools. Also, our project will delve into the details of how Ipv4, Ipv6 addresses are assigned over the network, how the Address Resolution Protocol (ARP) is used for finding a host's link layer (hardware) address/MAC address. and how through DHCP (Dynamic Host Configuration Protocol) lets a network administrator supervise and distribute IP addresses from a central point, with respect to local networks/Routers (we will use Linkysys WRT54AG router for testing) and even the Internet as a whole.
Linksys WRT45ABG
Nmap:
Linksys WRT45ABG
Nmap:
group06_Bandwidth Brothers : Transmission Media
Transmission media is the state which propagates energy waves. The state may be solid,liquid or gas. Our team will stress more on transmission media in networking as it is will be more useful for our subject. In our talk we would like to show visually the media type categories if possible and talk about it. The three main media type categories according to us are copper cable ( like coaxial cable), wireless ( such as microwaves used in LAN,infrared) and finally fibre optics (most expensive among the three). According to us none of them can be considered “the best” cause each has different use in different situation. So according to the need or situation we have to choose the best media. Also suppose if one fails we must have another to back upon, cause if events such as earthquake occurs if one media fails to work the other must be ready to use.We will be focussing mainly on the five traditionally used transmission media and explain everything related to it in detail. We would also rate the performance of they types of transmission media after thorough analysis. We would also like to download applications of transmission media and give a small demonstration. The basic understanding of transmission media will provide a good base for students studying computer communication. So to make everyone understand the basics of transmission media would be our team’s main aim. The five main transmission media which we will be focussing is twisted pair(used for voice applications), coaxial cable, microwave, satellite and finally fibre.
Group05_Illuminati:Transmission Media
On any network, the various entities must communicate through some form of media. Just as humans can communicate through telephone wires or sound waves in the air, computers can communicate through cables, light, and radio waves. Transmission media enable computers to send and receive messages but do not guarantee that the messages will be understood.
Our project will discuss some of the most common network transmission media, such as coaxial cable, shielded twisted-pair cable, and unshielded twisted-pair cable. We will also learn about network fiber-optic cable and wireless communications.
Our project will discuss some of the most common network transmission media, such as coaxial cable, shielded twisted-pair cable, and unshielded twisted-pair cable. We will also learn about network fiber-optic cable and wireless communications.
GROUP3_AMAK: Network protocol analysis
Network protocols defines a language of rules and conventions for communication between network devices.
List of Protocols with examples of each : -
1 Layer 1 protocols (Physical Layer)
- ADSL Asymmetric digital subscriber line
- ISDN Integrated Services Digital Network
2 Layer 2 protocols (Data Link Layer)
- Ethernet
- IEEE 802.11
- IEEE 802.16
Layer 3 protocols (Network Layer)
- IPv4 Internet Protocol version 4
- IPv6 Internet Protocol version 6
Layer 4 protocols (Transport Layer)
- TCP Transmission Control Protocol
- UDP User Datagram Protocol
Layer 5 protocols (Session Layer)
- NCP NetWare Core Protocol
- NFS Network File System
Layer 7 protocols (Application Layer)
- FTP, File Transfer Protocol
- HTTP, HyperText Transfer Protocol
- IMAP, Internet Message Access Protocol
- POP3 Post Office Protocol Version 3
- Telnet, a remote terminal access protocol
- SOAP, Simple Object Access Protocol
What is Network Protocol Analysis and Protocol Analyzer?
The packet analyzer (also known as a network protocol) is computer software or computer hardware that can intercept and log traffic passing over a digital network or part of a network.
Network protocol analysis is a process for a program or a device to decode network protocol headers and trailers to understand the data and information inside the packet encapsulated by the protocol. To conduct protocol analysis, packets must be captured at real time for line speed analysis or later analysis. Such program or device is called a Protocol Analyzer.
The uses of network analysers :
- Analyze network problems
- Detect network intrusion attempts
- Gain information for effecting a network intrusion
- Monitor network usage
- Gather and report network statistics
- Filter suspect content from network traffic
- Spy on other network users and collect sensitive information such as passwords
- Debug client/server communications
- Debug network protocol implementations
Notable Network analysis applications : -
- dSniff
- Microsoft Network Monitor
- Wireshark (formerly known as Ethereal)
- Snoop (part of Solaris)
- OPNET Technologies ACE Analyst
Group13_Avani:Protocol stack and addressing
A protocol stack/communication stack is a particular software implementation of a computer networking protocol suite.
The Open System Interconnection Reference Model (OSI Reference Model or OSI Model) is an abstract description for layered communications and computer network protocol design. It is a prescribed hierarchy of software layers, starting from the application layer at the top to the physical layer at the bottom. The stack resides in each client and server.
The Open System Interconnection Reference Model (OSI Reference Model or OSI Model) is an abstract description for layered communications and computer network protocol design. It is a prescribed hierarchy of software layers, starting from the application layer at the top to the physical layer at the bottom. The stack resides in each client and server.
OSI MODEL
LAYER -FUNCTION
7. Application -Network process to application
6. Presentation -Data representation and encryption
5. Session -Interhost communication
4. Transport -End-to-end connections and reliability
3. Network -Path determination and logical addressing
2. Data link -Physical addressing
1. Physical -Media, signal and binary transmission
A client application sends data down its protocol stack, passing through each of the protocols and interfaces. At the receiving side, the data packets traverse a similar stack of protocols and programs, this time in reverse. Starting at the physical layer, the packet passed through each successive layer until it reaches the top of the stack at the relevant application process. At each layer, the information appended by the different protocols is examined so that the host can forward the packet to its final destination. For the host to accomplish this, both the client and the host need to run the same program at each level.
To deliver data between two Internet hosts, it is necessary to move data across the network to the correct host, and within that host to the correct user or process. One of the schemes used by TCP/IP to accomplish these tasks is protocol stack addressing which deliver data to the correct host.
Specification used for multiple protocol stack addressing are:
• Media Access Control (MAC) driver: This is a device driver written by the vendors of the NIC that directly interfaces with the NIC hardware.
• Upper-Level Protocol driver
• Protocol manager program
To avoid confusion with MAC addresses, which are machine or station addresses, the term IP address will be used to designate this kind of address.Since the network and data link layer use different addressing schemes, some system is needed to convert or map the IP addresses to the MAC addresses. Transport-layer services and user processes use IP addresses to identify hosts, but packets that go out on the network need MAC addresses. The Address Resolution Protocol (ARP) is used to convert the 32-bit IP address of a host into its 48-bit MAC address. When a hosts wants to map an IP address to a MAC address, it broadcasts an ARP request on the network, asking for the host using the IP address to respond. The host that sees its own IP address in the request returns its MAC address to the sender. With a MAC address, the sending host can transmit a packet on the Ethernet and know that the receiving host will recognise it.
Group3_AMAK: How internet works?
The internet is a standardized, global system of interconnected computer networks that connects millions of people. The system uses IP/TCP standard rules for data representation. It carries a vast array of information resources and services in the form of interlinked hyper text documents of the world wide web(www) and the infrastructure to support electronic mail.
As we know that the internet is a global network of computers, each computer must have a unique address in the form of nnn.nnn.nnn.nnn where nnn ranges between 0-255. This unique address is known as IP address. If you connect to internet through an Internet Service Provider(ISP), you are assigned a temporary IP address for the session. If you connect to the internet through LAN(Local Area Network) you might be assigned a permanent IP address or a temporary one from DHCP(Dynamic Host Configuration Protocol) server.
Once the computer is connected to the internet and we want to communicate with the other computers, the message must be translated from alphabetic text to electronic signals and is sent over the medium through which it is connected. The receiving computer translates it back into alphabetic text and this is achieved through the use of protocol stack.The protocol stack used on the internet is referred to as TCP/IP protocol stack.
The protocol stack consists of layers that have different functions:
1.)Application Protocols layer: it is the protocol which is specific to the applications such as WWW,FTP,E-Mail.etc.
2.)Transmission Control Protocol Layer: directs packets to a specific application on a computer using a port number.
3.)Internet Protocol Layer: it directs packets to a specific computer using IP address.
4.)Hardware Layer: Converts binary packet data into network signals and back.
The data to be transmitted works its way downward the stack. The data to be transmitted is broken into smaller chunks of data known as packets.Each packet is assigned a port number.Port numbers are necessary because we need to determine the program on the computer which requires the information.From the TCP layer the packets proceed to the IP layer where they are assigned a destinatin IP address. Now that the packet has the port number and the IP address it proceeds to the hardware layer where it becomes ready to be sent over the internet. The packets work their way upwards in the protocol stack at the receiving computer. When the data reaches the top of the stack the data is reassembled in its original form.
The DNS is a distributed database which keeps track of computer's names and their corresponding IP addresses on the Internet. Many computers connected to the Internet host part of the DNS database and the software that allows others to access it. These computers are known as DNS servers. No DNS server contains the entire database; they only contain a subset of it. If a DNS server does not contain the domain name requested by another computer, the DNS server re-directs the requesting computer to another DNS server.
As we know that the internet is a global network of computers, each computer must have a unique address in the form of nnn.nnn.nnn.nnn where nnn ranges between 0-255. This unique address is known as IP address. If you connect to internet through an Internet Service Provider(ISP), you are assigned a temporary IP address for the session. If you connect to the internet through LAN(Local Area Network) you might be assigned a permanent IP address or a temporary one from DHCP(Dynamic Host Configuration Protocol) server.
Once the computer is connected to the internet and we want to communicate with the other computers, the message must be translated from alphabetic text to electronic signals and is sent over the medium through which it is connected. The receiving computer translates it back into alphabetic text and this is achieved through the use of protocol stack.The protocol stack used on the internet is referred to as TCP/IP protocol stack.
The protocol stack consists of layers that have different functions:
1.)Application Protocols layer: it is the protocol which is specific to the applications such as WWW,FTP,E-Mail.etc.
2.)Transmission Control Protocol Layer: directs packets to a specific application on a computer using a port number.
3.)Internet Protocol Layer: it directs packets to a specific computer using IP address.
4.)Hardware Layer: Converts binary packet data into network signals and back.
The data to be transmitted works its way downward the stack. The data to be transmitted is broken into smaller chunks of data known as packets.Each packet is assigned a port number.Port numbers are necessary because we need to determine the program on the computer which requires the information.From the TCP layer the packets proceed to the IP layer where they are assigned a destinatin IP address. Now that the packet has the port number and the IP address it proceeds to the hardware layer where it becomes ready to be sent over the internet. The packets work their way upwards in the protocol stack at the receiving computer. When the data reaches the top of the stack the data is reassembled in its original form.
The DNS is a distributed database which keeps track of computer's names and their corresponding IP addresses on the Internet. Many computers connected to the Internet host part of the DNS database and the software that allows others to access it. These computers are known as DNS servers. No DNS server contains the entire database; they only contain a subset of it. If a DNS server does not contain the domain name requested by another computer, the DNS server re-directs the requesting computer to another DNS server.
Group4_Newcreation:Network Protocal Analysis
Network protocol analysis is a process for a program or a device to decode network protocol headers and trailers to understand the data and information inside the packet encapsulated by the protocol. To conduct protocol analysis, packets must be captured at real time for line speed analysis or later analysis. Such program or device is called a Protocol Analyzer.network protocol defines a language of rules and convention for communication between network devices.
Network protocols include mechanisms for devices to identify and make connections with each other, as well as formatting rules that specify how data is packaged into messages sent and received. Some protocols also support message acknowledgement and data compression designed for reliable and/or high-performance network communication. Hundreds of different computer network protocols have been developed each designed for specific purposes and environments.
Internet Protocols:
The Internet Protocol family contains a set of related (and among the most widely used network protocols. Besides Internet Protocol (IP) itself, higher-level protocols like TCP, UDP, HTTP and FTP all integrate with IP to provide additional capabilities. Similarly, lower-level Internet Protocols like ARP and ICMP also co-exist with IP. These higher level protocols interact more closely with applications like Web browsers while lower-level protocols interact with network adapters and other computer hardware.
How Network Protocols Are Implemented:
Modern operating systems like Microsoft Windows contain built-in services or daemons that implement support for some network protocols. Applications like Web browsers contain software libraries that support the high level protocols necessary for that application to function. For some lower level TCP/IP and routing protocols, support is implemented in directly hardware (silicon chipsets) for improved performance.
Network protocols include mechanisms for devices to identify and make connections with each other, as well as formatting rules that specify how data is packaged into messages sent and received. Some protocols also support message acknowledgement and data compression designed for reliable and/or high-performance network communication. Hundreds of different computer network protocols have been developed each designed for specific purposes and environments.
Internet Protocols:
The Internet Protocol family contains a set of related (and among the most widely used network protocols. Besides Internet Protocol (IP) itself, higher-level protocols like TCP, UDP, HTTP and FTP all integrate with IP to provide additional capabilities. Similarly, lower-level Internet Protocols like ARP and ICMP also co-exist with IP. These higher level protocols interact more closely with applications like Web browsers while lower-level protocols interact with network adapters and other computer hardware.
How Network Protocols Are Implemented:
Modern operating systems like Microsoft Windows contain built-in services or daemons that implement support for some network protocols. Applications like Web browsers contain software libraries that support the high level protocols necessary for that application to function. For some lower level TCP/IP and routing protocols, support is implemented in directly hardware (silicon chipsets) for improved performance.
Group05_Illuminati:How Internet Works?
Internet is a global network of computers. Every computer that is connected to the Internet is part of a network. For example, a modem can be used to dial a local number to connect to an Internet Service Provider (ISP). At work, a local area network might be used but still connection to the Internet is made using an ISP that the company has contracted with. When a connection to an ISP is made, we become part of their network. The ISP may then connect to a larger network and become part of their network. The Internet is simply a network of networks.
Each computer connected to the Internet must have a unique address. This address is known as an IP (Internet Protocol) address. Every computer needs one to communicate on the Internet and it is usually built into the computer's operating system. The Internet uses a protocol stack referred to as the TCP/IP protocol stack because of the two major communication protocols used.The Internet backbone is made up of many large networks which interconnect with each other. These large networks are known as Network Service Providers or NSPs.These networks peer with each other to exchange packet traffic. Each NSP is required to connect to three Network Access Points or NAPs. At the NAPs, packet traffic may jump from one NSP's backbone to another NSP's backbone. NSPs also interconnect at Metropolitian Area Networks or MAEs. MAEs serve the same purpose as the NAPs but are privately owned. NAPs were the original Internet interconnect points. Both NAPs and MAEs are referred to as Internet Exchange Points or IXs. NSPs also sell bandwidth to smaller networks, such as ISPs and smaller bandwidth providers.The ISP maintains a pool of modems for their dial-in customers. This is managed by some form of computer (usually a dedicated one) which controls data flow from the modem pool to a backbone or dedicated line router. This setup may be referred to as a port server, as it 'serves' access to the network. Billing and usage information is usually collected here as well. No computer knows where any of the other computers are, and packets do not get sent to every computer. The information used to get packets to their destinations are contained in routing tables kept by each router connected to the Internet.. A router is usually connected between networks to route packets between them. Each router knows about it's sub-networks and which IP addresses they use. When a packet arrives at a router, the router examines the IP address put there by the IP protocol layer on the originating computer. The router checks it's routing table. If the network containing the IP address is found, the packet is sent to that network.After your packets traverse the phone network and your ISP's local equipment, they are routed onto the ISP's backbone or a backbone the ISP buys bandwidth from. From here the packets will usually journey through several routers and over several backbones, dedicated lines, and other networks until they find their destination,
Each computer connected to the Internet must have a unique address. This address is known as an IP (Internet Protocol) address. Every computer needs one to communicate on the Internet and it is usually built into the computer's operating system. The Internet uses a protocol stack referred to as the TCP/IP protocol stack because of the two major communication protocols used.The Internet backbone is made up of many large networks which interconnect with each other. These large networks are known as Network Service Providers or NSPs.These networks peer with each other to exchange packet traffic. Each NSP is required to connect to three Network Access Points or NAPs. At the NAPs, packet traffic may jump from one NSP's backbone to another NSP's backbone. NSPs also interconnect at Metropolitian Area Networks or MAEs. MAEs serve the same purpose as the NAPs but are privately owned. NAPs were the original Internet interconnect points. Both NAPs and MAEs are referred to as Internet Exchange Points or IXs. NSPs also sell bandwidth to smaller networks, such as ISPs and smaller bandwidth providers.The ISP maintains a pool of modems for their dial-in customers. This is managed by some form of computer (usually a dedicated one) which controls data flow from the modem pool to a backbone or dedicated line router. This setup may be referred to as a port server, as it 'serves' access to the network. Billing and usage information is usually collected here as well. No computer knows where any of the other computers are, and packets do not get sent to every computer. The information used to get packets to their destinations are contained in routing tables kept by each router connected to the Internet.. A router is usually connected between networks to route packets between them. Each router knows about it's sub-networks and which IP addresses they use. When a packet arrives at a router, the router examines the IP address put there by the IP protocol layer on the originating computer. The router checks it's routing table. If the network containing the IP address is found, the packet is sent to that network.After your packets traverse the phone network and your ISP's local equipment, they are routed onto the ISP's backbone or a backbone the ISP buys bandwidth from. From here the packets will usually journey through several routers and over several backbones, dedicated lines, and other networks until they find their destination,
Group18_awesum4sum: Undersatnding Computer Networks
Earlier a single computer served the whole organization's computational needs. But now a large number of seperate computers are capable of working individually and get the tasks done. But all these individual computers should be able to share and exchange the data and information in order to complete the organizational needs. This is possible by interconnecting the computers. These systems are called Computer Networks. There are two ways to communicate in a network. It can be a broadcast network, where a single communication channel is shared by all networks. The data is sent by any one of the system and any other system receives it. The system checks if the packets are intended for itself, if yes, it accepts the packets or it ignores. The data can also be sent to all the systems in the network. We can also have point to point networks, where there exists many computers between the source and the destination.
Group8_VintageBoys:TCPDump
TCPDUMP is a network protocol analyser which works on command line.it is the pre version of network protocol analysers like ethereal and wireshark
TCP Dump allows you to examine the header or content of each packet flowing over an interface or data link. To begin monitoring, select the desired interface from the "Monitor interface" popup and press "Start".
TCP Dump in IPNetMonitorX is a simple User Interface to the underlying unix "tcpdump" facility. Unix tcpdump has many options allowing you to specify in detail what packets you want to capture including protocols, interfaces, and link layer headers. The Options field accepts standard tcpdump options ("-n -p -t" for example to show numeric addresses, do not set promiscuous mode, and no time stamps).
Naturally you can run tcpdump directly from a terminal window if desired. The reason to incorporate TCP Dump in IPNetMonitorX is simple user convenience.
While TCP Dump is well suited to capturing packet headers and protocol information, it is less ideal for viewing the actual TCP data flow between a client and server. For this purpose, you can "Use TCP Flow" instead of TCP Dump. tcpflow is an open source utility distributed under GNU .
http://sustworks.com/site/prod_ipmx_help/html/TCPDumpHelp.html
The grab of TCPDUMP from ethereal
tcpdump is used on platforms like ethereal by network professionals for troubleshooting, analysis, software and protocol development. It has all of the standard features you would expect in a protocol analyzer, and several features not seen in any other product. Its open source licence allows people in the networking community to add enhancements. It runs on all popular computing platforms, including Unix, Linux, and Windows.although the windows version is enhanced with ethereal modern day network analyzers like wireshark are more popular and have made it redundant.
abridged from-http://www.ethereal.com/
parisparfait.typepad.com
tcpdump is used on platforms like ethereal by network professionals for troubleshooting, analysis, software and protocol development. It has all of the standard features you would expect in a protocol analyzer, and several features not seen in any other product. Its open source licence allows people in the networking community to add enhancements. It runs on all popular computing platforms, including Unix, Linux, and Windows.although the windows version is enhanced with ethereal modern day network analyzers like wireshark are more popular and have made it redundant.
abridged from-http://www.ethereal.com/
parisparfait.typepad.com
Group 10 _Fosters:understanding on computer networks
Computer network is basically concerned with a group of interconnected computers to share information and data. 
The above are the basic types of network used to connect computers.
the general types of computer networks are
Connections can be either wired or wireless (eg :bluetooth) depending upon our convenience.They can be intra connected using wires, hubs , routers and various different hardware components .
the general types of computer networks are
Connections can be either wired or wireless (eg :bluetooth) depending upon our convenience.They can be intra connected using wires, hubs , routers and various different hardware components .
group9_dead lock: IP utilities/ tcpdump
IP(Internet Protocol) is the primary network protocol allows us to create very large Internetwork by connecting individual networks together. when we send data between devices on different network, The data is routed between networks using IP. This permits us to view even a huge Internet work such as global Internet as if it were just a single large network. IP function at layer of OSI model it can therefore run on different data link interface including Ethernet and Wi-Fi. data on IP network is organized into packets. each packet includes both a header(source, destination and other information about data) and message itself.
IP/TCP three layers:-
* IP - its responsible for moving packet of data from node to node. IP forwards each packets based on a four byte destination address( IP number). IP operates on gateway machine that move data from department to organization to region and then around the world.
* TCP(transmission control protocol) - its responsible for verifying correct delivery of data from client to server. data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.
* Sockets - its a name given to the packages of subroutines that provide access to TCP/IP on most systems.
IP/TCP three layers:-
* IP - its responsible for moving packet of data from node to node. IP forwards each packets based on a four byte destination address( IP number). IP operates on gateway machine that move data from department to organization to region and then around the world.
* TCP(transmission control protocol) - its responsible for verifying correct delivery of data from client to server. data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger retransmission until the data is correctly and completely received.
* Sockets - its a name given to the packages of subroutines that provide access to TCP/IP on most systems.
group7_rothman:Transmission media
Transmission Media describes the type of physical system used to carry a communication signal from one system to another. Examples of transmission media include twisted-pair cable, coaxial cable, and fiber optic cable.
There are 2 basic categories of Transmission Media:
1. Guided
2. Unguided
Guided Transmission Media uses a "cabling" system that guides the data signals along a specific path. The data signals are bound by the "cabling" system. Guided Media is also known as Bound Media. Cabling is meant in a generic sense in the previous sentences and is not meant to be interpreted as copper wire cabling only.
There 4 basic types of Guided Media:
Open Wire
Twisted Pair
Coaxial Cable
Optical Fiber
Unguided Transmission Media consists of a means for the data signals to travel but nothing to guide them along a specific path. The data signals are not bound to a cabling media and as such are often called Unbound Media. The three guided media commonly used for transmission are twisted-pair,coaxial and fiber optic cable.
Unguided media,transmission and reception are achieved by means of an antenna.
The various types of waves used for wireless transmission are:
Terrestrial microwave
Satellite microwave
Broadcast radio
Infrared
Wireless propagation is through one of the following routers:
-Ground wave
-Sky wave
-Light of sight
Group 10_Fosters:IP/TCP
IP/TCP
TCP/IP defines the rule computers must follow to communicate with each other over the internet. It is the protocol suite that drives the Internet. Specifically, TCP/IP handles network communications between network nodes (computers, or nodes, connected to the net).The suite is actually composed of several protocols including IP which handles the movement of data between host computers, TCP manages the movement of data between applications.
About IP
IP is for communication between computers.It is a "connection-less" communication protocol. IP does not occupy the communication line between two computers. IP reduces the need for network lines. Each line can be used for communication between many different computers at the same time.With IP, messages (or other data) are broken up into small independent "packets" and sent between computers via the Internet.
IP is responsible for "routing" each packet to the correct destination.When an IP packet is sent from a computer, it arrives at an IP router. The IP router is responsible for "routing" the packet to the correct destination, directly or via another router.
About TCP
TCP is for communication between applications.If one application wants to communicate with another via TCP, it sends a communication request. This request must be sent to an exact address. After a "handshake" between the two applications, TCP will set up a "full-duplex" communication between the two applications.The "full-duplex" communication will occupy the communication line between the two computers until it is closed by one of the two applications.
TCP/IP defines the rule computers must follow to communicate with each other over the internet. It is the protocol suite that drives the Internet. Specifically, TCP/IP handles network communications between network nodes (computers, or nodes, connected to the net).The suite is actually composed of several protocols including IP which handles the movement of data between host computers, TCP manages the movement of data between applications.
About IP
IP is for communication between computers.It is a "connection-less" communication protocol. IP does not occupy the communication line between two computers. IP reduces the need for network lines. Each line can be used for communication between many different computers at the same time.With IP, messages (or other data) are broken up into small independent "packets" and sent between computers via the Internet.
IP is responsible for "routing" each packet to the correct destination.When an IP packet is sent from a computer, it arrives at an IP router. The IP router is responsible for "routing" the packet to the correct destination, directly or via another router.
About TCP
TCP is for communication between applications.If one application wants to communicate with another via TCP, it sends a communication request. This request must be sent to an exact address. After a "handshake" between the two applications, TCP will set up a "full-duplex" communication between the two applications.The "full-duplex" communication will occupy the communication line between the two computers until it is closed by one of the two applications.
Group16_QuadMasters:Remote Login
In the 1970s and early 1980s, text-oriented terminals were the predominate tools for computer users. Protocols such as TELNET and RLOGIN were developed for terminal users to use their terminals as if they were directly connected to a remote system. UNIX systems, with their predominately terminal-oriented interface, still make heavy use of these protocols.
In the late 1980s, as graphical, window-oriented user interfaces became popular, protocols were developed to allow remote windowing operations, much as earlier protocols allowed remote terminal operations. Although conceptually similar, the operation of such windowing protocols is markedly different.
Let's say we are preparing a huge PowerPoint presentation for a meeting on Friday. All of the PowerPoint files and PDFs and images that you want to use in your presentation are saved on the hard drive of your work computer.Thursday rolls around and you wake up with a nasty stomach virus.You don't feel well enough to go to the office, but you need to finish that presentation. Here's where remote login can help.
In simple words Remote Login means to access other computers on the network or on the other network by the use of telnet or rlogin command.In other words we can also say that Remote Login means to access native computer from the other computer on the network when you are connected to the internet.
Remote login, however, uses simple desktop sharing software to give you a "remote control" for accessing your computer and all of its software and hard drive files from any Internet-connected device anywhere in the world.
Remote login will only work if the host computer is powered on, connected to the Internet and running the desktop sharing software
Common tools used are:Telnet,SSH(secure shell),Putty,etc
In the late 1980s, as graphical, window-oriented user interfaces became popular, protocols were developed to allow remote windowing operations, much as earlier protocols allowed remote terminal operations. Although conceptually similar, the operation of such windowing protocols is markedly different.
Let's say we are preparing a huge PowerPoint presentation for a meeting on Friday. All of the PowerPoint files and PDFs and images that you want to use in your presentation are saved on the hard drive of your work computer.Thursday rolls around and you wake up with a nasty stomach virus.You don't feel well enough to go to the office, but you need to finish that presentation. Here's where remote login can help.
In simple words Remote Login means to access other computers on the network or on the other network by the use of telnet or rlogin command.In other words we can also say that Remote Login means to access native computer from the other computer on the network when you are connected to the internet.
Remote login, however, uses simple desktop sharing software to give you a "remote control" for accessing your computer and all of its software and hard drive files from any Internet-connected device anywhere in the world.
Remote login will only work if the host computer is powered on, connected to the Internet and running the desktop sharing software
Common tools used are:Telnet,SSH(secure shell),Putty,etc
group19_angels : http proxy server
A proxy server is one that receives requests intended for another server and that acts on the behalf of the client (as the client proxy) to obtain the requested service.Basically it acts as an intermediate between the client and the server. A proxy server is often used when the client and the server are incompatible for direct connection. It may also be used for screening purposes i.e for filtering purposes ,to enable the administrator to control access to undesirable sites. The proxy server may also be used for caching purposes which enables faster access to frequently used websites.
We will host a proxy server both in Linux/Windows and for the demonstration purpose, we will host a proxy server in our home router and computer, configure a dynamic DNS (through dyndns.org) to connect to it.
Our tool of choice is Squid:
We will host a proxy server both in Linux/Windows and for the demonstration purpose, we will host a proxy server in our home router and computer, configure a dynamic DNS (through dyndns.org) to connect to it.
Our tool of choice is Squid:
Group 1_Charisma : How does the internet work?
How did the Internet really get started? It all began with a satellite. In 1957 when the then Soviet Union launched Sputnik, the first man-made satellite, the cold war between the Russians and the Americans led to the then American President Dwight D. Eisenhower create the Advanced Research Projects Agency (ARPA) in 1958. ARPA's purpose was to give the United States a technological edge over other countries. It created a computer network which connected four computers running on four different operating systems. They called the network ARPANET. ARPANET laid the foundation for the present day internet.
Nobody owns the Internet. The Internet Society, a non-profit group established in 1992, monitors how we interact with the Internet.
Internet Protocol: IP Addresses:
Every machine on the Internet has a unique identifying number, called an IP Address. The IP stands for Internet Protocol, which is the language that computers use to communicate over the Internet. A protocol is the predefined way that someone who wants to use a service talks with that service. The "someone" could be a person, but more often it is a computer program like a Web browser.
A typical IP address looks like this:
216.27.61.137
To make it easier for us humans to remember, IP addresses are normally expressed in decimal format as a dotted decimal number like the one above. But computers communicate in binary form. The same IP address in binary looks like this:
11011000.00011011.00111101.10001001
All of these networks rely on Network Access Points or NAPs, backbones and routers to talk to each other.The Internet backbone is made up of many large networks which interconnect with each other. These large networks are known as Network Service Providers or NSPs. What is incredible about this process is that a message can leave one computer and travel halfway across the world through several different networks and arrive at another computer in a fraction of a second!
The routers determine where to send information from one computer to another. Routers are specialized computers that send your messages and those of every other Internet user speeding to their destinations along thousands of pathways. A router has two separate, but related, jobs:
* It ensures that information doesn't go where it's not needed. This is crucial for keeping large volumes of data from clogging the connections of "innocent bystanders."
* It makes sure that information does make it to the intended destination.
Protocol Stacks and Packets:
How does a computer with a unique IP address communicate with other computers connected to the Internet? An example should serve here: Let's say your IP address is 1.2.3.4 and you want to send a message to the computer 5.6.7.8. Obviously, the message must be transmitted over whatever kind of wire connects your computer to the Internet. Let's say you've dialed into your ISP(Internet Service Provider) from home and the message must be transmitted over the phone line. Therefore the message must be translated from alphabetic text into electronic signals, transmitted over the Internet, then translated back into alphabetic text. This is accomplished through the use of a protocol stack. Every computer needs one to communicate on the Internet and it is usually built into the computer's operating system (i.e. Windows, Unix, etc.). The protocol stack used on the Internet is referred to as the TCP(Transmission Control Protocol)/IP protocol stack because of the two major communication protocols used.
The ISP maintains a pool of modems for their dial-in customers. This is managed by some form of computer (usually a dedicated one) which controls data flow from the modem pool to a backbone or dedicated line router. This setup may be referred to as a port server, as it 'serves' access to the network. Billing and usage information is usually collected here as well.
After your packets traverse the phone network and your ISP's local equipment, they are routed onto the ISP's backbone or a backbone the ISP buys bandwidth from. From here the packets will usually journey through several routers and over several backbones, dedicated lines, and other networks until they find their destination, the computer with address 5.6.7.8. This is how the internet works.
Nobody owns the Internet. The Internet Society, a non-profit group established in 1992, monitors how we interact with the Internet.
Internet Protocol: IP Addresses:
Every machine on the Internet has a unique identifying number, called an IP Address. The IP stands for Internet Protocol, which is the language that computers use to communicate over the Internet. A protocol is the predefined way that someone who wants to use a service talks with that service. The "someone" could be a person, but more often it is a computer program like a Web browser.
A typical IP address looks like this:
216.27.61.137
To make it easier for us humans to remember, IP addresses are normally expressed in decimal format as a dotted decimal number like the one above. But computers communicate in binary form. The same IP address in binary looks like this:
11011000.00011011.00111101.10001001
All of these networks rely on Network Access Points or NAPs, backbones and routers to talk to each other.The Internet backbone is made up of many large networks which interconnect with each other. These large networks are known as Network Service Providers or NSPs. What is incredible about this process is that a message can leave one computer and travel halfway across the world through several different networks and arrive at another computer in a fraction of a second!
The routers determine where to send information from one computer to another. Routers are specialized computers that send your messages and those of every other Internet user speeding to their destinations along thousands of pathways. A router has two separate, but related, jobs:
* It ensures that information doesn't go where it's not needed. This is crucial for keeping large volumes of data from clogging the connections of "innocent bystanders."
* It makes sure that information does make it to the intended destination.
Protocol Stacks and Packets:
How does a computer with a unique IP address communicate with other computers connected to the Internet? An example should serve here: Let's say your IP address is 1.2.3.4 and you want to send a message to the computer 5.6.7.8. Obviously, the message must be transmitted over whatever kind of wire connects your computer to the Internet. Let's say you've dialed into your ISP(Internet Service Provider) from home and the message must be transmitted over the phone line. Therefore the message must be translated from alphabetic text into electronic signals, transmitted over the Internet, then translated back into alphabetic text. This is accomplished through the use of a protocol stack. Every computer needs one to communicate on the Internet and it is usually built into the computer's operating system (i.e. Windows, Unix, etc.). The protocol stack used on the Internet is referred to as the TCP(Transmission Control Protocol)/IP protocol stack because of the two major communication protocols used.
The ISP maintains a pool of modems for their dial-in customers. This is managed by some form of computer (usually a dedicated one) which controls data flow from the modem pool to a backbone or dedicated line router. This setup may be referred to as a port server, as it 'serves' access to the network. Billing and usage information is usually collected here as well.
After your packets traverse the phone network and your ISP's local equipment, they are routed onto the ISP's backbone or a backbone the ISP buys bandwidth from. From here the packets will usually journey through several routers and over several backbones, dedicated lines, and other networks until they find their destination, the computer with address 5.6.7.8. This is how the internet works.
Group2_OldBridge::How does LAN work
LAN: Local area network.
A local area network (LAN) supplies networking capability to a group of computers in close proximity to each other such as in an office building.
There are many kinds of LAN networks such as Client-Server network in which there exists a dedicated server, peer-to-peer network in which there are no servers, but each computer works as a server.
In LAN the computers are connected through a certain medium like optical fiber or data cables which provides the pathway for electrical signals in between computers. The transmission and receiving of data is controlled by an administrator who authorizes the file access, sharing of files etc.. In LAN network, each computers are equipped with communication device called network adapter.
A network adapter interfaces a computer to a network. The term "adapter" was popularized originally by Ethernet add-in cards for PCs.
Modern network adapter hardware exists in several forms. Besides traditional PCI Ethernet cards, some network adapters are PCMCIA devices (also know as "credit card" or "PC Card" adapters) or USB devices. Some wireless network adapter gear for laptop computers are integrated circuit chips pre-installed inside the computer.
For ex: Assume two computers, say COMPUTER A and COMPUTER B are connected by a LAN newtork, Computer A contains a printer and Computer B doesn't have printer, B will be able to access A's printer through LAN and print the required pages from the A's printer as if it were its own.
group11_DNAA:protocol stack
A protocol stack is a complete set of network protocol layers that work together to provide networking capabilities. It is called as stack because it is designed as a hierarchy of layers, each supporting one above it and using those below it. A protocol is a mutually agreed upon format for doing something. With regard to computers, it most commonly refers a set of rules that enables computers to connect and transmit data to one another. A protocol can be implemented by hardware, software or a combination of the two.
Regardless of the number of layers, the lowest protocols always deal with low level, physical interaction of the hardware. Each higher layer adds additional features, an user applications typically interact only with the uppermost layers. The layers can be broadly classified as media, transport and application.
The media-to-transport interface defines how transport protocol software makes use of particular media and hardware types. The application-to-transport interface defines how application programs make use of the transport layers.
Example of protocol stack and corresponding layers:
Protocol----- Layer
1. HTTP----- Application
2. TCP------- Transport
3. IP ---------Internet
4. Ethernet--- Link
Regardless of the number of layers, the lowest protocols always deal with low level, physical interaction of the hardware. Each higher layer adds additional features, an user applications typically interact only with the uppermost layers. The layers can be broadly classified as media, transport and application.
The media-to-transport interface defines how transport protocol software makes use of particular media and hardware types. The application-to-transport interface defines how application programs make use of the transport layers.
Example of protocol stack and corresponding layers:
Protocol----- Layer
1. HTTP----- Application
2. TCP------- Transport
3. IP ---------Internet
4. Ethernet--- Link
group20_dynamic networks:ftp,http proxy servers
HTTP defines how messages are formatted and transmitted, and what actions Web servers
and browsers should take in response to various commands.One of the most popular uses of the internet is to download/ upload files that is transfer files
from a computer on the internet to your computer and vise versa which is achieved through FTP
A proxy server that all computers on the local network have to go through before accessing information on the Internet.which improves the network performance and filter what users connected to the network can access.Proxy servers have two main purposes i.e improve performance and filter requests.Proxy servers dramatically increase the speed of the web-searching,performance,etc and also it takes off the load from the 'main'server.We must find new ways of improving the blocking of unauthorised sites and improve the performance so that it reduces cost while handling more data/information.a http proxy allows a user to change their IP online and remain completely anonymous. Using anything less than a HTTP based proxy server will either risk revealing your identity online or being unable to access many websites and their content.
and browsers should take in response to various commands.One of the most popular uses of the internet is to download/ upload files that is transfer files
from a computer on the internet to your computer and vise versa which is achieved through FTP
A proxy server that all computers on the local network have to go through before accessing information on the Internet.which improves the network performance and filter what users connected to the network can access.Proxy servers have two main purposes i.e improve performance and filter requests.Proxy servers dramatically increase the speed of the web-searching,performance,etc and also it takes off the load from the 'main'server.We must find new ways of improving the blocking of unauthorised sites and improve the performance so that it reduces cost while handling more data/information.a http proxy allows a user to change their IP online and remain completely anonymous. Using anything less than a HTTP based proxy server will either risk revealing your identity online or being unable to access many websites and their content.
Group15_Krazzy4:Remote Login
Remote Login is the process of connecting to an internet host to use its native user interface. In simple words Remote Login means to access other computers on the network or on the other network by the use of telnet or rlogin command. To explain in simple terms let us assume that 'X' is preparing a presentation in the cluster lab for a Vo'ISE event to be held tomorrow. Unfortunately 'X' gets diagnosed with stomach ache and is not able to come to college the day before the event. But he has to finish the presentation at any cost for the event. WHAT does he do?
This is where remote login comes into picture. Remote login however, uses simple desktop sharing software to give us a "remote control" for accessing our computer and all of its software and hard drive files from any Internet connected device anywhere in the world. So now 'X' can access the computer in the cluster lab using the process of remote login. For remote login to work, both the host computer and all remote users have to download and install the same desktop sharing software. Thus remote login has proved to be a boon to access computers in other parts of the world.
This is where remote login comes into picture. Remote login however, uses simple desktop sharing software to give us a "remote control" for accessing our computer and all of its software and hard drive files from any Internet connected device anywhere in the world. So now 'X' can access the computer in the cluster lab using the process of remote login. For remote login to work, both the host computer and all remote users have to download and install the same desktop sharing software. Thus remote login has proved to be a boon to access computers in other parts of the world.
Group4_Newcreation:How does Internet works
Introduction:
Internet is the global network of computers each computer connected to the internet must have a unique address internet address are in the form nnn.nnn.nnn.nnn where nnn must be a number from 0 to 255 this address is known as an IP address.
Computer ----> Internet ----> Computer.
If the computer is connected to the internet through an Internet Service Provider (ISP),the computer will be assigned the temporary IP address for the duration of your dial-in session.If the is connected to the internet through local area network (LAN) it will have a permanent IP address or it might obtain a temporary one from a DHCP (Dynamic Host Configuration Protocal)
server.
Computer Internal Communication Via Internet:
As we know computer has a unique IP address lik comp A has 1.2.3.4 and the comp B may have 5.6.7.8 and if these two computers wants to communicate, and if comp A want to send a "Hello" message to comp B then the message must be transmitted over watever kind of wire connects both the computer to the internet.Lets say both the computer have dialed to ISP from home and the message must be transmitted over the phone line.there fore the message must be transmitted from Alphabetic text in to electronic signals transmited over the internet, then transmitted back in to Alphabetic text.
A simple flow:
Comp A:Application-> TCP -> IP -> Hardware -->INTERNET-->CompB: Hardware -> IP ->TCP -> Application
Internet is the global network of computers each computer connected to the internet must have a unique address internet address are in the form nnn.nnn.nnn.nnn where nnn must be a number from 0 to 255 this address is known as an IP address.
Computer ----> Internet ----> Computer.
If the computer is connected to the internet through an Internet Service Provider (ISP),the computer will be assigned the temporary IP address for the duration of your dial-in session.If the is connected to the internet through local area network (LAN) it will have a permanent IP address or it might obtain a temporary one from a DHCP (Dynamic Host Configuration Protocal)
server.
Computer Internal Communication Via Internet:
As we know computer has a unique IP address lik comp A has 1.2.3.4 and the comp B may have 5.6.7.8 and if these two computers wants to communicate, and if comp A want to send a "Hello" message to comp B then the message must be transmitted over watever kind of wire connects both the computer to the internet.Lets say both the computer have dialed to ISP from home and the message must be transmitted over the phone line.there fore the message must be transmitted from Alphabetic text in to electronic signals transmited over the internet, then transmitted back in to Alphabetic text.
A simple flow:
Comp A:Application-> TCP -> IP -> Hardware -->INTERNET-->CompB: Hardware -> IP ->TCP -> Application
group19_angels:how does internet work
Internet is simply computers connected in a network.All these computers connected in a network are assigned a unique IP address provided by the server or the router.If we connect to the Internet through an Internet Service Provider (ISP), we are assigned with a temporary IP address for the duration of your dial-in session. If we connect to the Internet from a local area network (LAN) our computer might have a permanent IP address or it might obtain a temporary one from a DHCP (Dynamic Host Configuration Protocol) server.if we have to access a web page something of the kind www.google.com ,then it connects to the domain name service (DNS)server which keeps a track of all the computer names and their corresponding IP addresses.Here google also has a unique IP address and only after DNS server matches its IP address ,the accessor gets to see the web page he/she is looking for on his/her computer.If it does not find the address of the particular computer ,the request will be forwarded to another DNS server.
Group9_dead lock: How do you think a LAN works?
LAN(local area netwok) is used to connect systems which are in short range. e.g for an institute which has to communicate regularly or a scientific research lab which has to share devices/resources worth lakhs. LAN are generally called hub switches in which other computer sit virtually. The main computer generally called the server will have a LAN card installed, In modern days Ethernet cards are used. The connection between LAN card and switches are done through RJ-45 cables. When a computer has to communicate with other for data transfer it establish a dynamic or static IP address. e.g 192.168.1.4 , after which the client can access any data or device on other LAN computer as if it was in the client machine itself. LAN can be used for bidirectional use like playing games which require continuous data exchange. while data is been transfered the data packets will have the ip address of the client which requested the transfer.
group14_indigo:Remote Login
As far as our understanding on the topic is concerned, Remote Login is how one can access other computer on the network when connected to the internet.For example if a company is serving a client who is at a far distance from the company and if a problem arises in the client system, then by using the concept of remote login the company can solve the clients problem by accesing the clients system through remote login.
For the successful implementation of remote login three basic components are required.They are:
For the successful implementation of remote login three basic components are required.They are:
- Software Download
- Internet Connection
- Secure Desktop Sharing Network.
- Remote Easy IP Finder 0.1
- Win-Spy Software 8.0
- Rlogin Overview Protocol
- Remote Administrator 2.2
- Telnet Overview Protocol
- Putty
Since we are familiar with the basic concepts of UNIX, the rlogin command can be used for the purpose of remote login.The usage of rlogin command is yet to be learnt.
group7_rothman:how does internet work??
Internet is a global network of computers each computer connected to the internet must have a unique address.Internet addresses are in the form of nnn.nnn.nnn.nnn. where nnn must be a number from 0-255.This address is known as the IP address.
If we connect to the internet through a internet service protocol (ISP), we are usually assigned a temporary IP address for the duration of the dial-in session.If we connect to the internet from a local area network(LAN) the computer might have a permanent IP address or it might have a temporary one from DHCP (dynamic host configuration protocol) server.In any case if you are connected to the internet and the computer will have a unique IP address.
The backbone of the Internet consists of a powerful set of telephone lines including T3 lines, capable of transferring data at a very fast rate of about 45 megabyte per second. The lines link metropolitan cities and include national access points or feeds.The backbone of the Internet is operated and maintained by various companies and organizations working cooperatively without centralized ownership. Redundancy is built into the backbone of the Internet so that if one or more major lines go down, traffic can be rerouted, much like a traffic detour when a highway is temporarily under construction. While this might slow Internet traffic, it will not ‘break’ the Internet.
Any one who is connected to the internet can send and receive information over the internet by using internet enabled softwares. When you point-and-click on a link, your browser sends out a request that is addressed to the website that houses the content you want.When the data packet arrives at the website, the server reads the request and sends the requested page back to your computer via a return address in the data packet this is your computer’s IP address.The data packet is routed back to you , your browser interprets the content and displays the page for you.
If we connect to the internet through a internet service protocol (ISP), we are usually assigned a temporary IP address for the duration of the dial-in session.If we connect to the internet from a local area network(LAN) the computer might have a permanent IP address or it might have a temporary one from DHCP (dynamic host configuration protocol) server.In any case if you are connected to the internet and the computer will have a unique IP address.
The backbone of the Internet consists of a powerful set of telephone lines including T3 lines, capable of transferring data at a very fast rate of about 45 megabyte per second. The lines link metropolitan cities and include national access points or feeds.The backbone of the Internet is operated and maintained by various companies and organizations working cooperatively without centralized ownership. Redundancy is built into the backbone of the Internet so that if one or more major lines go down, traffic can be rerouted, much like a traffic detour when a highway is temporarily under construction. While this might slow Internet traffic, it will not ‘break’ the Internet.
Any one who is connected to the internet can send and receive information over the internet by using internet enabled softwares. When you point-and-click on a link, your browser sends out a request that is addressed to the website that houses the content you want.When the data packet arrives at the website, the server reads the request and sends the requested page back to your computer via a return address in the data packet this is your computer’s IP address.The data packet is routed back to you , your browser interprets the content and displays the page for you.
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