Connected: An Internet Encyclopedia

 Wednesday 20 August 2008 18:24:13 1219256653
Flow Control

Up: Connected: An Internet Encyclopedia
Up: Topics
Up: Concepts

Prev: Encapsulation
Next: Request/Reply

Flow Control

Flow Control Modern data networks are designed to support a diverse range of hosts and communication mediums. Consider a 200MHz Pentium-based host transmitting data to a 25MHz 80386/SX. Obviously, the Pentium will be able to drown the slower processor with data. Likewise, consider two hosts, each using an Ethernet LAN, but with the two Ethernets connected by a 28.8 Kbps modem link. If one host begins transmitting to the other at Ethernet speeds, the modem link will quickly become overwhelmed. In both cases, flow control is needed to pace the data transfer at an acceptable speed.

Request/reply flow control requires each data packet to be acknowledge by the remote host before the next packet is sent. Sliding window algorithms, used by TCP, permit multiple data packets to be in simultaneous transit, making more efficient use of network bandwidth. Finally, Internet's Unreliable Delivery Model allows packets to be discarded if network resources are not available, and demands that protocols make provisions for retransmission.

Next: Request/Reply

Connected: An Internet Encyclopedia
Flow Control

 

 

Associate sites:

Cheap domain names registration, Buy domain name and domain register, web hosting service or domain hosting
 

This site is sponsored by the courtesy of Active-Domain.com
 
If all our misfortunes were laid in one common heap, whence everyone must take an equal portion, most people would be content to take their own and depart.