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

Student, Explain how the os implements virtual memory phenomenon.

Explain how the os implements virtual memory phenomenon.

Explain basic file system file system architecture, Basic File System ...

Basic File System Uses the specific device driver. Deals with blocks of data that are exchanged with the physical device. Concerned with the placement of blocks on

Independent process, what is independent process? distinguished between ind...

what is independent process? distinguished between independent process and co-operating process

Write note on process, Write note on process, process state? A process ...

Write note on process, process state? A process is in excess of the program code which is sometimes known as text section. It as well includes the current activity as represent

Define input - output operations, Q. Define Input - Output operations? ...

Q. Define Input - Output operations? Serial lines, Disks, tapes and other devices should be communicated with at a very low level. The user require only specify the device and

Define the os/2 threads code, Define the OS/2 threads code The sample p...

Define the OS/2 threads code The sample program in Listing is very similar to the NetWare example. OS/2 commands are substituted for the pseudocode commands controlling thread

Explain linked list allocation using index, Linked list allocation using in...

Linked list allocation using index The blocks don't have a fixed size. Pointers are utilized to point to the next block in a file. The pointers are set aside as a separate tabl

Estimate the continued transfer rate of drive, Q. The term "fast wide SCSI...

Q. The term "fast wide SCSI-II" signifies a SCSI bus that operates at a data rate of 20 megabytes per second when it moves a packet of bytes among the host and a device. Presume t

What is starvation?, What is starvation? A main problem related to dead...

What is starvation? A main problem related to deadlock is starvation. Starvation is the circumstances where process waits indefinitely within the semaphore. Indefinite blocking

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