A new adaptive method to optimize SCTP during vertical handover in UMTS/WLAN integrated networks

Next generation wireless communications are expected to rely on integrated networks consisting of multiple wireless technologies. Integrated networks based on Wireless Local Area Networks (WLAN) and Universal Mobile Telecommunications System (UMTS) can combine their respective advantages on coverage and data rates, offering a high Quality of Service (QoS) to mobile users. In such environment, multi-interface terminals should seamlessly switch from one network to another in order to obtain improved performance or at least to maintain a continuous wireless connection. Vertical handover (VHO) refers to a network node changing the type of connectivity it uses to access a supporting infrastructure, usually to support node mobility. This paper proposes a new method to facilitate seamless vertical handover between wide area cellular data networks such as UMTS and WLANs using the Stream Control Transmission Protocol (SCTP). To improve the performance of SCTP during vertical handover in UMTS/WLAN integrated network an adaptive method for bandwidth estimation and congestion control is intended. Finally we will evaluate our proposed method using OPNET Modeller simulations.