Our setup:
	Application Layer (us)
	Transport Layer (TCP)
	Internet Layer (IPv4)
	Data Link Layer (802.3 Ethernet)
		Some of you have 802.11 (wifi) instead

First:  A simple demo
Client and server in C, talking to each other

Homework 1:  Easy at this point

Expanding a bit:  Stream nature of TCP
	Let's send a string with a little delay in the middle

Order will be preserved, and no bytes lost
	Let's try reading only part of a message
		We can read in any pattern we like

Separation of messages:
	Let's look at how protocols do this
	How does 802.3 know where the end of a frame is?
	How does IP know the quantity of data in a packet?
	How does TCP know how much data to expect?
	We can do something like that too

Read a particular quantity:
	recv with MSG_WAITALL