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

Batch oriented and interactive operating system., properies of Batch orient...

properies of Batch oriented and interactive operating system.

Describe the concept of transaction atomicity, Q. Describe the concept of t...

Q. Describe the concept of transaction atomicity? Answer: A transaction is a sequence of read as well as writes operations upon some data followed by a commit operation. If the

Explain the reasons why an organisation fail to plan, Problem 1: (a) Wh...

Problem 1: (a) What are the likely benefits which an organisation may derive from the planning process? (b) Explain the main reasons why an organisation may fail to plan.

Crank-nicolson timestepping schemes, For the heat conduction problem, inves...

For the heat conduction problem, investigate the effects on the numerical solution of the following aspects: 1. non-uniform meshes with re?nement at both ends versus a uniform m

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.

What is paging? name the different paging techniques, What is paging? Name ...

What is paging? Name the different paging techniques. Paging is a memory management method that permits the physical-address space of a process to be noncontiguous. Paging evad

Explain additional-reference-bits algorithm, Additional-reference-bits algo...

Additional-reference-bits algorithm We can keep an 8-bit byte for every page in a table in memory. The operating system shifts the reference bits right 1 bit, discarding the lo

How is a process chosen for being swapped either in or out?, How is a proce...

How is a process chosen for being swapped either in or out? Swap out: a.         If the process is idle. b.         If process has been in main memory for a long time.

Explain first fit allocation algorithm, Describe the following allocation a...

Describe the following allocation algorithms: a. First fit b. Best fit c. Worst fit   a. First-fit: search the list of available memory and all

Write a short note on pcb, Write a short note on PCB? Every process is ...

Write a short note on PCB? Every process is represented in the operating system by a process control block also called a task control block. It contains more information regard

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