VoIP Codec Adaptation Algorithm in Multirate 802.11 WLANs: Distributed vs. Centralized Performance Comparison
نویسندگان
چکیده
Multirate 802.11 environments are quite problematic for VoIP traffic, with the rate changes of some of the flows affecting the transmission of all others. Building upon our previous results, we propose an algorithm which, based on the combined feedback from Real-Time Control Protocol (RTCP) packets and the MAC layer, can dynamically adapt the codecs of ongoing VoIP calls to adjust them to the multirate scenario. A comparison of both the centralized and distributed versions of the algorithm is provided for a wired-wireless scenario, showing an important capacity and quality increase over the standard case.
منابع مشابه
A cross-layer mechanism for QoS improvements in VoIP over multi-rate WLAN networks
VoIP over WLANs has become a hot research topic during the past years due to the widespread deployment and ease-of-use of both technologies. Nevertheless, this widespread (and especially the commercial) deployment of VoIP over WLANs, cannot be ultimately successful unless most of the VoIP quality of service issues are solved efficiently. The 802.11 standard, as most of the IP-related technologi...
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