Improvements on “IP – IAPP”: A fast IP handoff protocol for IEEE 802.11 wireless and mobile clients

Abstract

One of the most critical issues in introducing Wireless LAN (WLAN) real-time and delay sensitive applications, such as Voice over IP (VoIP), is guaranteeing IP service continuation during inter-subnet Basic Service Set (BSS) transitions. Even though WLANs offer very high channel bandwidth, they exhibit long network-layer handoff latency. This is a restraining factor for mobile clients using interactive multimedia applications such as VoIP or video streaming. In a previous work, we presented a novel fast and efficient IP mobility solution, called "IP-IAPP", which offers constant IP connectivity to the 802.11 mobile users and successfully preserves their ongoing sessions, even during subnet handoffs (fast recovery of active connections). It is an 802.11-dependent IP mobility solution, which accelerates the network reconfiguration phase after subnet handoffs and significantly reduces the IP handoff latency. It restores L3 connectivity almost simultaneously to the L2 connectivity after a subnet handoff, due to a zero-delay movement detection method. As a result, even the most demanding next generation WLAN applications such as Voice over WLAN (VoWLAN) suffer insignificant disruption. In this paper we present an improved version of the IP-IAPP mobility mechanism (new optimized protocol procedures). Certain extensions have also been incorporated to the initial proposal, for the provision of more advanced services: (a) secure inter-AP IP-IAPP communications, (b) zero patching on the clients s/w, and (c) support of clients which use a dynamic IP address. Performance measurements out of further and more complex testing verify that the proposed method outperforms other existing mobility solutions, and still introduces the lesser imperative amendments to the existing 802.11 wireless LAN framework.

A Robust Mobile Video Streaming in Heterogeneous Emerging Wireless Systems

“…For independence between L2 handover and L3 handover, IEEE 802 has been developing standards to enable interoperable handover between heterogeneous networks [46][47] [25]. In special, IEEE 802.21 specification defines Media Independent Handover (MIH) primitives to provide the link layer intelligence and other related network information to the upper layers to optimize handovers between heterogeneous media [13][26].…”

“…However, this scheme has limits to implement and needs the additional layer in each MN. To support the seamless handover between the specific heterogeneous emerging wireless networks such as cellular and wireless local area networks [21] or IEEE 802.16e broadband wireless access system [22] or UMTS-WLAN [23] or WiBro System [24] or 802.11 [25], they provides details on the use of the framework or algorithms for the seamless handover. Reference [21] has introduced a framework that can be used for integrating cellular and WLANs.…”

“…As a result, it reduces the handover latency, packet loss and eliminates the out-of order problem by integrating L2 and L3 handovers efficiently. Reference [25] presents an effective and simple solution in IEEE 802.11 wireless LANs (WLANs) using IP tunneling mechanism. However, these handover schemes are only applied to the specific wireless networks and did not consider QoS applications such as the video streaming.…”

A seamless handoff scheme for IEEE 802.11 wireless networks

“…In Refs. [22,23], the authors extended IEEE 802.11f IAPP protocol too, and named it as IP-IAPP. They use BSs to serve as mobility agents.…”

Optimization of 802.11b/g Networks for High Mobility and Dynamic Data Applications

“…This information is sent using UDP handoff [6][7][8]. However, these works imply modifications application from a central node (CN) through the on the protocols and standards used.…”