TCP notes

A packet goes through many hops, can I just deal with sender and receiver and not worry about anybody in-between? In other words, why shall I worry about how post office works?

end to end vs hop by hop

connection vs connectionless

reliable vs unreliable transport

stream vs datagram

TCP vs UDP

We know we can have multiple "TAB" to the same web site. How does it work?

What happens to each TAB?

How do I distinguish them?

Port number, what is that?

well-known port, ubiquitous port

A room, how do I know the room # for an application (e.g. web server)?

TCP connection state machine

How do I start/stop a TCP connection?

.. understanding the TCP state machine (both server and client) is essential ..

3 way handshaking

header

4 way close (it can be 3 packets)

How does TCP achieve "reliable transport"?

mechanism to assure reliable streaming

sequence number

acknowledge number

re-transmission

timeout, how does sender decide the timeout value?

exponential back-out

mechanism for flow control

sliding window, window size advertisement from receiver

+++++++++++++++++++++++++++++++++++++++++++extra

++ socket programming to make a TCP connection

++ optional headers.. MSS

Congestion Control

Shall I pump in as much traffic as I get them?

How do I detect a network congestion?

What do I do when network is congested?

Can receiver do anything to help the de-congestion?