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

Array-initialization loops using lru replacement algorithm, Q. Consider th...

Q. Consider the two-dimensional array A: int A[][] = new int[100][100]; Whereas A [0][0] is at location 200 in a paged memory system with pages of size 200. A little process

Demand paging, Demand paging gives that pages could only be brought into ...

Demand paging gives that pages could only be brought into memory if the running process acts them. This is usually referred to as lazy evaluation as only those pages operated by

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

Android operating system, Android operating system is an open source, Linux...

Android operating system is an open source, Linux-based Smartphone OS. It is the world's most popular mobile platform with more than 700,000 applications and 25 billion downlo

How can a user program disturb the normal operation, How can a user program...

How can a user program disturb the normal operation of the system? a) Issuing illegal I/O operation. b) By accessing memory locations within the OS itself. c) Refusing to

Pstree, Construct a process tree similar to Figure 1. Look up the Linux com...

Construct a process tree similar to Figure 1. Look up the Linux command pstree -p and describe what it does. Then type in the command the capture the output.

Explain how a domain user account is authenticated, Question: a) The fo...

Question: a) The following questions pertain to User and Group accounts in Windows XP: i) Give four differences between a Power User and a Guest User account. ii) Explain h

Kernel to context switch between kernel level threads, Q. Explain the actio...

Q. Explain the actions taken by a kernel to context switch between kernel level threads. Answer: Context switching among kernel threads classically requires saving the value

Write knowledge base relevant propositional statement, Suppose a logic-base...

Suppose a logic-based agent in the wumpus world has found that locations (1,1) and (2,1) do not contain a stench, but that locations (3,1) and (2,2) do contain a stench. Can the ag

Explain concept of synchronization, Synchronization In communication am...

Synchronization In communication among processes messages passed may be blocking or nonblocking - also called as synchronous and asynchronous. Blocking send : The sending pr

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