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

Network operating system and a distributed operating system, Problem: (...

Problem: (a) (i) Explain what a single system image is and how it is related to the concept of a distributed operating system? (ii) What are the main differences between a

An operating system for a real-time environment, Q. What is the major diffi...

Q. What is the major difficulty that a programmer should overcome in writing an operating system for a real-time environment? Answer: The major difficulty is keeping the oper

Explain producer-consumer problem using semaphores, Producer-Consumer Probl...

Producer-Consumer Problem Using Semaphores The Solution to producer-consumer problem use three semaphores namely- full, empty and mutex. The semaphore 'full' is utilized for

What methods are used to monitor intrusion detection, Question : a) Wh...

Question : a) What do you understand by a Directory Structure? Support your answer with a diagram. b) Give an example how Access Lists and Groups are arranged to mode of

Total physical memory and total virtual memory , A practical task specified...

A practical task specified in the Study Guide, Computer architecture, was to record your computer's specifications. Submit the data you recorded, which will contain the following d

Unix , A friend has promised to log in at a particular time. However, he ne...

A friend has promised to log in at a particular time. However, he needs to be contacted as soon as he logs in. The shell script checks after every minute whether he has logged in o

Unsafe state, discuss unsafe state in operating system

discuss unsafe state in operating system

Give an overview of unix based file systems, Give an overview of UNIX based...

Give an overview of UNIX based file systems. UNIX and UNIX-like operating systems allocate a device name to each device, other than this isn't how the files on that device are

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