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

Define caching, Define caching. A cache is a region of fast memory that...

Define caching. A cache is a region of fast memory that holds copies of data. Access to the cached copy is well-organized than access to the original. Caching and buffering are

Sector sparing, What is sector sparing is proper definition

What is sector sparing is proper definition

Explain process states in the unix system, Process States A total of n...

Process States A total of nine states are acknowledged by the UNIX system. They are like as follow: User running                                                   Executing

Example of semaphore, For example, by initializing a semaphore to 0, thread...

For example, by initializing a semaphore to 0, threads can wait for an event to occur, and impose an ordering constraint, similar to a monitor using condition variables, but with m

Allocating new pages, Processes have valid and invalid entries on their pag...

Processes have valid and invalid entries on their page tables. The valid entries all point to some where "real" (e.g. a physical page, or some portion of disk in case of non-reside

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 external fragmentation?, Explain external fragmentation? Extern...

Explain external fragmentation? External fragmentation is the process where the free space and the space still available for use, in a piece of storage become separated into ma

Calculate the average waiting time, Calculate the Average Waiting Time ...

Calculate the Average Waiting Time CPU burst time points out the time, the process needs the CPU. The subsequent are the set of processes with their respective CPU burst time (

Describe the benefits of using microkernels, Question: (a) (i) What is ...

Question: (a) (i) What is a microkernel? Describe the benefits of using microkernels. (ii) How does a microkernel-based operating system differ from a traditional operating

Why we need to use a while statement when using wait method, Q. The wait()...

Q. The wait() statement in every Java program examples was part of a while loop. Describe why you would always need to use a while statement when using wait() and why you would ne

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