Policy-based flow control for multi-homed mobile terminals with IEEE 802.11u standard

Article history: Available online xxxx Keywords: WLAN 802.11u Policy Flow control Mobility a b s t r a c t The latest IEEE 802.11u extends the highly popular IEEE 802.11-2007 standard towards supporting inter-working with external networks. It however relies on a single 802.11 network interface card only, which fails to support simultaneous access of 802.11 and non-802.11 services. As such, multiple heterogenous wireless network services have yet to be effectively utilized. In this paper, we suggest to extend the original 802.11u STA (STAtion) address allocation and management, which enables multi-homing for 802.11u single interface STA by deploying the MCOA-MIP6 protocol in the network layer (layer 3). We further develop policy flow control for both up-link and down-link packets toward better QoS for mobile users and better resource utilization for carriers. We have implemented our proposal in a Linux-based testbed. The experimental results have proven that our policy-based flow control mechanism provides better user experience. It also effectively achieves load balancing and enhances fault tolerance. With the rapid development and deployment of the mobile Internet, the coexistence of heterogeneous wireless mobile networks such as wireless local area network (WLAN) and 3G networks has become common for one location. Meanwhile, an increasing number of user handsets are equipped with multiple network interfaces, enabling potential Internet access through multiple heterogeneous access technologies [1–3]. Since different access technologies offer different levels of QoS, coverage, band-width and capacity, it is necessary to choose the most suitable network for each application flow. For instance, a device may prefer to use WiFi to download a large file, while receive a video stream through the long term evolution (LTE) network. While theoretically possible, the simultaneous multi-access however has yet to be well supported by hosts or by networks. On the host side, the default gateway is often selected as the interface for sending packets. On the network side, packets forwarding in routers remain largely based on destination addresses. Therefore , it remains difficult to apply different policies for interface selection with multi-homed mobile terminal, for downlink or for uplink [4]. There have been significant efforts to fill up the gap. Typical examples include the concurrent multipath transfer extension of stream control transmission protocol (CMT-SCTP) [5] and the mul-ti-path TCP (MPTCP) [6] in the transport layer; The host identify protocol (HIP) [7] between the transport and network layers; The multiple care-of address registration for mobile IPv6 (MCoA-MIP6) [4,8] …