Internet Layer In The Tcp Ip Model example essay topic
Relative to the OSI reference model, provides layer 2 (data-link layer) service. Essentially, it packages your computer's TCP / IP packets and forwards them to the server where they can actually be put on the Internet. is a full-duplex protocol that can be used on various physical media, including twisted pair or fiber optic lines or satellite transmission. is usually preferred over the earlier standard SLIP because it can handle synchronous as well as asynchronous communication. can share a line with other users and it has error detection that SLIP lacks. Where a choice is possible, is preferred. HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files (text, graphic images, sound, video, and other multimedia files) on the Web.
As soon as a Web user opens their Web browser, the user is indirectly making use of HTTP. HTTP is an application protocol that runs on top of the TCP / IP suite of protocols. HTTP concepts include the idea that files can contain references to other files whose selection will elicit additional transfer requests. Your Web browser is an HTTP client, sending requests to server machines. When the browser user enters file requests by either 'opening' a Web site or clicking on a link, the browser builds an HTTP request and sends it to the Internet Protocol address indicated by the URL. File Transfer Protocol (FTP), a standard Internet protocol, is the simplest way to exchange files between computers on the Internet.
FTP is an application protocol that uses the Internet's TCP / IP protocols. FTP is commonly used to transfer Web page files from their creator to the computer that acts as their server for everyone on the Internet. It's also commonly used to download programs and other files to your computer from other servers. As a user, you can use FTP with a simple command line interface or with a commercial program that offers a graphical user interface.
Your Web browser can also make FTP requests to download programs you select from a Web page. Using FTP, you can also update files at a server. You need to logon to an FTP server. However, publicly available files are easily accessed using anonymous FTP. Basic FTP support is usually provided as part of a suite of programs that come with TCP / IP. However, any FTP client program with a graphical user interface usually must be downloaded from the company that makes it.
TCP (Transmission Control Protocol) is a set of rules used along with the Internet Protocol to send data in the form of message units between computers over the Internet. While IP takes care of handling the actual delivery of the data, TCP takes care of keeping track of the individual units of data that a message is divided into for efficient routing through the Internet. TCP is known as a connection-oriented protocol, which means that a connection is established and maintained until such time as the message or messages to be exchanged by the application programs at each end have been exchanged. TCP is responsible for ensuring that a message is divided into the packets that IP manages and for reassembling the packets back into the complete message at the other end. In the OSI model, TCP is in layer 4, the Transport Layer.
The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. Each computer on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet. When you send or receive data, the message gets divided into little chunks called packets. Each of these packets contains both the sender's Internet address and the receiver's address.
Any packet is sent first to a gateway computer that understands a small part of the Internet. The gateway computer reads the destination address and forwards the packet to an adjacent gateway that in turn reads the destination address and so forth across the Internet until one gateway recognizes the packet as belonging to a computer within its immediate neighborhood or domain. That gateway then forwards the packet directly to the computer whose address is specified. Because a message is divided into a number of packets, each packet can, if necessary, be sent by a different route across the Internet. Packets can arrive in a different order than the order they were sent in. The Internet Protocol just delivers them.
It's up to another protocol, the Transmission Control Protocol to put them back in the right order. IP is a connection less protocol, which means that there is no continuing connection between the end points that are communicating. Each packet that travels through the Internet is treated as an independent unit of data without any relation to any other unit of data. In the OSI Model, IP is in layer 3, the Networking Layer. In fact, the Internet and TCP / IP are so closely related in their history that it is difficult to discuss one without also talking about the other. They were developed together, with TCP / IP providing the mechanism for implementing the Internet.
TCP / IP has over the years continued to evolve to meet the needs of the Internet and also smaller, private networks that use the technology. The TCP / IP protocols were initially developed as part of the research network developed by the United States Defense Advanced Research Projects Agency (DARPA or ARPA). Initially, this fledgling network, called the ARPAnet, was designed to use a number of protocols that had been adapted from existing technologies. The developers of the new network recognized that trying to use these existing protocols might eventually lead to problems as the ARPAnet scaled to a larger size and was adapted for newer uses and applications. In 1973, development of a full-fledged system of internet working protocols for the ARPAnet began. What many people don't realize is that in early versions of this technology, there was only one core protocol: TCP.
And in fact, these letters didn't even stand for what they do today; they were for the Transmission Control Program. The lowest layer of the OSI Reference Model is the physical layer, which is responsible for the smallest details of transmitting information from one place to another on a network. The layer just above the physical layer is the data link layer, called the network interface layer or just the link layer in the TCP / IP architectural model. Its primary job is to implement networks at the local level, and to interface between the hardware-oriented physical layer, and the more abstract, software-oriented functions of the network layer and those above it. The second layer of the OSI Model is the data link layer; it corresponds to the TCP / IP network interface layer. It is there that most LAN, WAN and WLAN technologies are defined, such as Ethernet and I 802.11.
The third layer is the network layer, also called the internet layer in the TCP / IP model, where internet working protocols are defined, the most notable being the Internet Protocol. These two layers are related, because messages sent at the network layer must be carried over individual physical networks at the data link layer. They perform different tasks but as neighbors in the protocol stack, must cooperate with each other. The third OSI layer is the network layer. We are of course talking about networks in this Guide, and it is no coincidence that the layer bearing that name is one of the most important in comprehending how networks function. It is here that we find protocols that tie networks together to create internet works, and also where cross-network addressing and routing are performed.
The network layer is also called the internet layer in the TCP / IP model.