Wireless ATM AVD Networks - Network Architecture

Physical Layer

• Working model of custom physical layer for wireless ATM
• Use various existing systems
  • cellular system with modems
  • packet radio modems
• Unreliable delivery
• Provides byte framing

Link Layer

• Frame structure
  • interleaving
  • retransmission
  • FEC
• Retransmission, FEC policy based on traffic class
  • delay-sensitive uses FEC
  • error-sensitive uses retransmission

ATM Layer

• Possibilities
  • standard ATM cell structure
  • modified cell structure for narrowband
• Standard network management and signaling
• Initial support for rapid mobility limited
• Use GPS in future systems
  • handoff prediction
  • virtual circuit setup

Higher Layers

• TCP/IP header compression (based on SLIP code)
• Use available Mobile-IP implementation
• Berkeley TCP modifications?