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

Explain deadlock avoidance, Deadlock Avoidance It's a method to evade ...

Deadlock Avoidance It's a method to evade deadlock by careful resource scheduling. This approach to the deadlock problem foresees deadlock before it actually occurs. This a

Write a short note on disk scheduling, Write a short note on disk schedulin...

Write a short note on disk scheduling   One of the responsibities of operating system O/S is to use the hardware efficiently. Whenever a process requires I/O to or from the

What is logical address space and physical address space, What is logical a...

What is logical address space and physical address space? The set of all logical addresses formed by a program is known as a logical address space; the set of all physical addr

Define an assembly language, Define an assembly language  Assembly lan...

Define an assembly language  Assembly language stands for a Low level programming language

Explain file, What is a file? A named collection of related data explai...

What is a file? A named collection of related data explained by the creator, recorded on secondary storage.

What is the sequence in which resources may be utilized, What is the sequen...

What is the sequence in which resources may be utilized? Under normal mode of operation, a process may utilize a resource in the following sequence: Request: If the requ

What is the main function of the memory-management unit, What is the main f...

What is the main function of the memory-management unit? The runtime mapping from virtual to physical addresses is done by a hardware device known as a memory management unit (

Explain medium term scheduling, Medium term scheduling This is componen...

Medium term scheduling This is component of the swapping function. Usually the swapping in decision is based on the need to manage the degree of multiprogramming. At a system t

Transferring files from windows to unix, Transferring files from Windows to...

Transferring files from Windows to Unix Be very careful transferring files from Windows to Unix. If you do transfer a file from Windows to Unix open the file, in Unix, using vi

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