Computer Networking - Essay Example

What is a client program? What is server program? How pop works? (5) Answer: A networking program usually has clients programs and servers programs, each running on a different host and communicating with each other. The program that initiates the communication is the client. Typically, the client program sends service requests to server and server program provide service to client. Informally, clients tend to be desktop and mobile PC’s, Smartened, and so on, whereas servers tend to be more powerful machines that store and distribute Web pages, stream video, relay e-mail, and so on.

Today, most of the servers from which we receive search results, e- mail, Web pages, and videos reside in large data centers. For example, Google has 30-50 data centers, with many having more than one hundred thousand servers. In a POP network, the “peers” are computer systems which are connected to each other via the Internet. Files can be shared directly between systems on the network without the need of a central server. In other words, each computer on a POP network becomes a file server as well as a client.

POP allows us to search for files on other people’s computers. Meanwhile, other users on the network can search for files on my computer, but typically only within a single folder that we have designated to share Suppose you are developing for new type of packet switched network. You need to decide whether you work your network will use Vs. or datagram routing. What are the pros and cons for using Vs.? (5) Answer: In my network I will use vs..

The cons of Vs. include The need to have a signaling protocol to set-up and tear-down the Vs.; The need to maintain connection state in the packet switches For the pros, Some researchers and engineers argue that it is easier to provide So services – such s services that guarantee a minimum transmission rate or services that guarantee maximum end-to-end packet delay – when Vs. are used. What are the five layers in the internet protocol stack? What are the principles responsibilities for each of these layers? 5) Answer: The five layers in the Internet protocol stack are – from top to bottom – Application layer, Transport layer, Network layer, Link layer, Physical layer. The principal responsibilities are given bellow: Application layer: The application layer is responsible for supporting network applications. Transport layer: The transport layer is responsible for transporting application-layer messages between the client and server sides of an application. Network layer: The network layer is responsible for routing datagram from one host to another.

Link layer: The link layers are responsible for handling communication over a specific link . The network layer routes a packet through a series of packet switches (I. E. , routers) between the source and destination. To move a packet from one node (host or packet switch) to the next node in the route, the network layer must rely on the services of the link layer. Physical layer: The physical layer and link layers re responsible for handling communication over a specific link, they are typically implemented in a network interface card (e. G. Ethernet or ATM interface cards) associated with a given link. What is the difference between persistent HTTP with pipelining and persistent HTTP without pipelining? Which of the two use by HTTP/I . 1? (5) Answer: In persistent HTTP with pipelining, the browser issues requests as soon as it has a need to do so, without waiting for response messages from the server. In persistent HTTP without pipelining, the browser first waits to receive a HTTP response room the server before issuing a new HTTP request. HTTP/I . 1 uses persistent connection with pipelining as its default.