Voice communications over IEEE 802.11 wireless LANs interconnected using ATM links

Abstract

This paper presents a new polling scheme that can be used at the access point of an IEEE 802.11 wireless network as part of the point coordination function, in order to provide guaranteed QoS support of voice traffic. The so called cyclic shift polling scheme, along with the use of silence detection at the mobile terminals, increases the supported number of calls as a function of the overall rate of dropped voice packets and the point coordination function repetition interval. The advantages of utilizing this polling scheme are demonstrated by using the voice delay and voice jitter distributions. The delay and jitter distributions confirm that the voice packet delay introduced by the wireless network can be less than 25 ms even in the case of stations of different wireless networks when the IEEE 802.11 LANs are interconnected via an ATM infrastructure.