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

What is multiprogramming, Q. What is Multiprogramming? Multiprogrammin...

Q. What is Multiprogramming? Multiprogramming When two or more programs are in memory at the same instance, sharing the processor is referred to multiprogramming opera

Difference between preemptive and nonpreemptive scheduling, Define the diff...

Define the difference between preemptive and nonpreemptive scheduling. State why strict nonpreemptive scheduling is unlikely to be used in a computer center. Preemptive schedul

Multi-level page tables, Multi-level page tables are tree-like structures t...

Multi-level page tables are tree-like structures to hold page tables. As an example, consider a two- level page table, again on a 32-bit architecture with 212 = 4 kbyte pages. Now,

Explain micro-kernel, Operating Systems 1. Explain Micro-kernel? Specif...

Operating Systems 1. Explain Micro-kernel? Specify the benefits of Micro-kernel? 2. Describe seven state process models used for OS with necessary diagram. Differentiate bet

What are files and explain the access methods for files, What are files and...

What are files and explain the access methods for files? File definition Attributes, operations and types Direct access Sequential access with diagram Other access

Explain the resource ownership by platform, Explain the Resource Ownership ...

Explain the Resource Ownership by Platform Ownership of data items may further be complicated by concepts defined in certain operating systems. Each operating system defines "p

Explain linked allocation, Linked allocation With linked allocation, ev...

Linked allocation With linked allocation, every file is a linked list of disk blocks; the disk blocks might be scattered anywhere on the disk. The directory has a pointer to th

Name the hardware to support demand paging, The hardware to support demand ...

The hardware to support demand paging is as follows Page table: This table has the skill to mark an entry invalid though a valid-invalid bit or particular value of protectio

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