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

Deadlock involving only one single process, Is it probable to have a deadlo...

Is it probable to have a deadlock involving only one single process? Describe your answer. Answer: No This pursue directly from the hold-and-wait condition.

Programable clock modes in computer systems, Ask question #Minimuexplain th...

Ask question #Minimuexplain the programable clock modes in a computer system m 100 words accepted#

What is symmetric multiprocessing, Symmetric multiprocessing To get ma...

Symmetric multiprocessing To get maximum reliability and efficiency a mode of function called as symmetric multiprocessing is used. In essence, with SMP any program or threads

Removing system dependencies, Removing System Dependencies Because port...

Removing System Dependencies Because portions of the client - server application program may execute on different machines, it is very important for the developer to remove the

How does dma raise system concurrency, Q. How does DMA raise system concurr...

Q. How does DMA raise system concurrency? How does it make difficult hardware design? Answer: DMA increases system concurrency by allowing the CPU to perform tasks while the

Define cpu scheduling, Define CPU scheduling. CPU scheduling is the met...

Define CPU scheduling. CPU scheduling is the method of switching the CPU among several processes. CPU scheduling is the basis of multiprogrammed operating systems. By switching

Os, why we say" OS is a resource allocator" and “OS is a control program"?

why we say" OS is a resource allocator" and “OS is a control program"?

search tree generated by hill-climbing search, Show the search tree genera...

Show the search tree generated by Hill-Climbing search (text figure 4.2, page 122; or Local Search lecture, slide 6) for each of the two heuristics (a) and (b) applied to the follo

Explain a computing environment, Q. Polling for an I/O completion is able ...

Q. Polling for an I/O completion is able to waste a large number of CPU cycles if the processor iterates a busy-waiting loop several times before the I/O completes. However if the

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