Packetized voice transmission using RT-MAC, a wireless real-time medium access control protocol

ABSTRACT

RT-MAC is a simple, elegant, and robust medium access control (MAC) protocol for use in transmitting real-time data in point-to-point ad hoc wireless local area networks (WLANs). Our enhancement of IEEE 802.11, real-time MAC (RT-MAC), dramatically reduces missed deadlines and packet collisions while increasing throughput by selectively discarding packets and sharing station state information. For example, RT-MAC is able to successfully transmit 40 2-way voice conversations in addition to a normalized offered load of 80%. IEEE 802.11 is only able to transmit 10 2-way conversations under the same conditions. In another instance, RT-MAC reduced packet collisions from 50% to less than 15% while increasing throughput by more than 50%. Herein we extend our previous performance analysis of RT-MAC to include integrated voice-data transmission. Stations using RT-MAC are interoperable with stations using IEEE 802.11 and show a significant performance improvement even when a minority of stations in the network employ RT-MAC.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design
          Subjects: Wireless communication

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.5 Local and Wide-Area Networks
          Subjects: Access schemes
  C.4 PERFORMANCE OF SYSTEMS
      Subjects: Performance attributes

General Terms:
Algorithms, Performance