Networking tidbits, Operating System

Assignment Help:

There is a very small amount of networking background required for Project 2. In Project 2, we want our computer (or our "host") to request information over the Internet from a remote webserver (another Internet "host"). On our computer, from within our Project 2 ap-plication, we will open a "socket", which on many operating systems acts like a ?le which you can read or write. Moving down the network stack into the operating system, a socket uses a transport protocol to communicate with the remote host. The application-layer HTTP protocol which webservers use is built on top of the transport-layer TCP protocol, which provides reliable, in-order, stream-based delivery between your socket and the remote socket. A socket also has a "port" number associated with it. When we open our socket, we will request that it opens port 80 on the remote host, since this is the port number on which almost all webservers listen for re-quests.  Finally, when opening the socket, we need to specify which remote webserver we want to communicate with, such as www.cnn.com, etc. Moving down one more layer, every host (laptop, server, cell phone, etc) which is directly accessible on the Internet has a unique network-layer IP address, such as 128.119.240.19, and most of those have hostnames, such as www.cs.umass.edu; the Domain Name Service (DNS) translates from hostnames to IP addresses.

Note that the sock.read() method is in a while-loop, since reading from a socket will return between one byte and the maximum number of bytes requested ((MAX READ-1-size) in the code above). You'll need to keep repeatedly reading from the socket again until you get all the bytes you want. sock.read() will block until it has at least one byte to return, unless its request times out (set by sock.setTimeout(5) to be 5 seconds), or unless the connection is closed.


Related Discussions:- Networking tidbits

What is multiprogramming, What is Multiprogramming? Multiprogramming is...

What is Multiprogramming? Multiprogramming is the capability of am operating system to support multiple applications running concurrently. Multiprogramming simply means that an

Define some language processors, Define Name of some language processors?  ...

Define Name of some language processors?   Name of some language processors are as follow: Assembler, Compiler and Interpreter

Explain concept of buffering, Buffering Messages exchanged by communica...

Buffering Messages exchanged by communication processes reside in a impermanent queue. Such a queue can be executed in three ways. Zero capacity: The queue length is 0.

Explain debugging a multi threaded program, Debugging a multi threaded prog...

Debugging a multi threaded program The following list points out few of the more frequent oversights and errors that can cause bugs in multithreaded programs. 1.    Ephemeral

Prevention of a data race in a parallelised program, Present your own fully...

Present your own fully documented and tested programming example illustrating the prevention of a data race in a parallelised program. This is an example where total number of p

Describe the differences among short-term and medium-term, Describe the dif...

Describe the differences among short-term, medium-term, and long-term scheduling.   Short-term (CPU scheduler)-selects from jobs in memory those jobs that are ready to execu

Define projected allocation state is safe - banker algorithm, A system cons...

A system consists of 10 units of resource class Ru. The resource needs of three user processes P1, P2 and P3 are like this                     Using Banker's algorithm, de

Thread safety, What does it mean for something to be thread-safe? By saying...

What does it mean for something to be thread-safe? By saying that X is thread-safe, we mean that if multiple threads use X at the same time, we don't have to worry about concurrenc

What is the use of the command interpreter, Q. What is the use of the comma...

Q. What is the use of the command interpreter? Why is it generally separate from the kernel? Answer: It reads commands from the user or else from a file of commands and execu

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd