Bridges

• Used to interconnect LANs
  • Autonomous Departments
  • Geographical Spread
  • Load Splitting
  • Reliability (Firewall)
  • Security (Promiscuous Listeners)
• For each port, build a Forwarding Data Base
• Learning Phase
  • If destination LAN is unknown, use flooding.
  • Learn Source!
• Forwarding Phase
  • If destination and source LANs are same, discard frame.
  • Otherwise, forward frame on correct port.
• Difference between a bridge and a switch?