Multiplexing/demultiplexing

multiplexing/demultiplexing:

based on sender, receiver port numbers, IP addresses
- source, dest port #s in each segment
- recall: well-known port numbers for specific applications

gathering data from multiple

app processes, enveloping

data with header (later used

for demultiplexing)

source port #

dest port #

32 bits

application

data

(message)

other header fields

TCP/UDP segment format