1
1
Introduction
Outline
Statistical Multiplexing
Inter-Process Communication
Network Architecture
Performance Metrics
2
Building Blocks
• Nodes: PC, special-purpose hardware…
– hosts
– switches
• Links: coax cable, optical fiber…
– point-to-point
– multiple access …
3
Switched Networks
– two or more nodes
connected by a link, or
– two or more networks
connected by two or
more nodes
• A network can be defined recursively as...
4
Strategies
• Circuit switching: carry bit streams
– original telephone network
• Packet switching: store-and-forward messages
– Internet
5
Addressing and Routing
• Address: byte-string that identifies a node
– usually unique
• Routing vs Forwarding
• Types of addresses
– unicast: node-specific
– broadcast: all nodes on the network
– multicast: some subset of nodes on the network
6
Multiplexing
• Time-Division Multiplexing (TDM)
• Frequency-Division Multiplexing (FDM)
L1
L2
L3
R1
R2
R3
Switch 1 Switch 2
