A New Technique to Expedite RSVP Path Re-establishments in 802.11 Wireless LANs

This paper proposes a novel scheme that exploits the Inter Access Point Protocol (IAPP), currently standardized by IEEE, in order to expedite the RSVP path re-establishment that takes place after a handover from one WLAN Access Point (AP) to another. The prime characteristic of this scheme is that a WLAN AP serves as an RSVP proxy and starts RSVP signaling on behalf of the Mobile Node much earlier compared with the standard RSVP operation in a WLAN. Therefore, a considerable handover latency reduction can be achieved, which can be as high as 20%. To evaluate the performance and the benefits of the proposed scheme, we display and discuss a series of simulation results. In addition, we present in detail its operation and we discuss the RSVP objects that should be transferred across APs through IAPP. In this context, we also explain the structure of the proposed RSVP Information Elements. Our simulation results show considerable performance improvement, especially in heavy traffic load conditions. Note that the proposed scheme can work with the standard RSVP protocol, as well as with partial path re-establishment methods and can be combined with advanced admission control algorithms in the AP.