TY - JOUR
T1 - 100+ VoIP Calls on 802.11b
T2 - The power of combining voice frame aggregation and uplink-downlink bandwidth control in wireless LANs
AU - Yun, Sangki
AU - Kim, Hyogon
AU - Lee, Heejo
AU - Kang, Inhye
PY - 2007/5
Y1 - 2007/5
N2 - The bandwidth efficiency of Voice over IP (VoIP) traffic on the IEEE 802.11 WLAN is notoriously low. VoIP over 802.11 incurs high bandwidth cost for voice frame packetization and MAC/PHY framing, which is aggravated by channel access overhead. For instance, 10 calls with the G.729 codec can barely be supported on 802.11b with acceptable QoS - less than 2% efficiency. As WLANs and VoIP services become increasingly widespread, this inefficiency must be overcome. This paper proposes a solution that boosts the efficiency high enough to support a significantly larger number of calls than existing schemes, with fair call quality. The solution comes in two parts: adaptive frame aggregation and uplink/downlink bandwidth equalization. The former reduces the absolute number of MAC frames according to the link congestion level, and the latter balances the bandwidth usage between the access point (AP) and wireless stations. When used in combination, they yield superior performance, for instance, supporting more than 100 VoIP calls over a IEEE 802.11b link. We demonstrate the performance of the proposed approach through extensive simulation, and validate the simulation through analysis.
AB - The bandwidth efficiency of Voice over IP (VoIP) traffic on the IEEE 802.11 WLAN is notoriously low. VoIP over 802.11 incurs high bandwidth cost for voice frame packetization and MAC/PHY framing, which is aggravated by channel access overhead. For instance, 10 calls with the G.729 codec can barely be supported on 802.11b with acceptable QoS - less than 2% efficiency. As WLANs and VoIP services become increasingly widespread, this inefficiency must be overcome. This paper proposes a solution that boosts the efficiency high enough to support a significantly larger number of calls than existing schemes, with fair call quality. The solution comes in two parts: adaptive frame aggregation and uplink/downlink bandwidth equalization. The former reduces the absolute number of MAC frames according to the link congestion level, and the latter balances the bandwidth usage between the access point (AP) and wireless stations. When used in combination, they yield superior performance, for instance, supporting more than 100 VoIP calls over a IEEE 802.11b link. We demonstrate the performance of the proposed approach through extensive simulation, and validate the simulation through analysis.
UR - http://www.scopus.com/inward/record.url?scp=34249340853&partnerID=8YFLogxK
U2 - 10.1109/JSAC.2007.070506
DO - 10.1109/JSAC.2007.070506
M3 - Article
AN - SCOPUS:34249340853
SN - 0733-8716
VL - 25
SP - 689
EP - 698
JO - IEEE Journal on Selected Areas in Communications
JF - IEEE Journal on Selected Areas in Communications
IS - 4
ER -