Flows¶

This is a summary of the roles, attributes, and design of flows.

Abstract¶

In this case, flows are in charge of transport layer. There are three main part of transport layer:

Error Control
Congestion Control
Flow Control

They are all features of TCP protocol. Different versions of TCP protocol employ different strategies.

Error Control: How to retransmit¶

Three basic strategies

Stop-and-wait
Go Back N
Selective Acknowledgments

Congestion Control: What’s window size; Avoid saturating routers¶

Basic strategies

AIMD: additive increase, multiple decrease
Fast Retransmit and Fast Recovery
Adjust Rate

Note

What’s “Adjust Rate”?

Flow Control: Avoid saturating destination¶

When sending ack packet, the destination inform how many buffers left.

What we need to do¶

Realize all the features
Combine different features so we have different versions of TCP