A Cross-Layer Solution for VoIP over IEEE802.11

The deployment of WLANs was meant to extend LANs, with no particular care for real-time applications. Nevertheless, since VoIP calls are becoming customary, IEEE802.11 WLANs are challenged with the provision of guaranteed quality VoIP calls. In this paper, we address the concerns on the efficiency of WLAN for VoIP provision, and propose a cross-layer scheme aimed to enhance the voice capacity of the current typical WLAN configuration. With the proposed modification, the overhead of the IEEE802.11 MAC is mitigated allowing the aggregation of VoIP packets of the same flow. We show through extensive simulations that the advantage of our scheme is significant, while being compliant with the current IEEE802.11 standard. Keywords— IEEE802.11, VoIP, Cross-Layer.

[1]  Juan Carlos De Martin,et al.  Adaptive Interactive Speech Transmission Over 802.11 Wireless LAN , 2003 .

[2]  Marceau Coupechoux,et al.  Voice over IEEE 802.11b Capacity , 2004 .

[3]  Ansi Ieee,et al.  Part11 : Wireless LAN Media Access Control (MAC) and Physical Layer (PHY) Specifications , 1999 .

[4]  Sunghyun Choi,et al.  Enhancement of VolP over IEEE 802.11 WLAN via dual queue strategy , 2004, 2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577).

[5]  Sachin Garg,et al.  Can I add a VoIP call? , 2003, IEEE International Conference on Communications, 2003. ICC '03..

[6]  Sunghyun Choi,et al.  Analysis of IEEE 802.11e for QoS support in wireless LANs , 2003, IEEE Wireless Communications.

[7]  Fouad A. Tobagi,et al.  Capacity of an IEEE 802.11b wireless LAN supporting VoIP , 2004, 2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577).

[8]  Henning Schulzrinne,et al.  RTP: A Transport Protocol for Real-Time Applications , 1996, RFC.

[9]  Malathi Veeraraghavan,et al.  Support of voice services in IEEE 802.11 wireless LANs , 2001, Proceedings IEEE INFOCOM 2001. Conference on Computer Communications. Twentieth Annual Joint Conference of the IEEE Computer and Communications Society (Cat. No.01CH37213).

[10]  Adam Wolisz,et al.  Voice transmission in an IEEE 802.11 WLAN based access network , 2001, WOWMOM '01.

[11]  Toshikazu Kodama,et al.  Voice capacity of IEEE 802.11b, 802.11a and 802.11g wireless LANs , 2004, IEEE Global Telecommunications Conference, 2004. GLOBECOM '04..

[12]  Soung Chang Liew,et al.  Solutions to performance problems in VoIP over a 802.11 wireless LAN , 2005, IEEE Transactions on Vehicular Technology.