Cooperative end-to-end roaming through homogeneous and heterogeneous networks

In the last few years, a large variety of wireless components are increasingly running applications that need real-time and high-bandwidth features. Hence, it is imperative for network service providers to make the best possible to ensure seamless roaming through different wireless technologies. In this context, mobility management remains an important task to be investigated to improve Quality of Service (QoS) during the handover disruption time. With the standardization of SCTP/mSCTP protocols, experiencing mobility at the transport layer becomes more attractive due to the high connectivity facilities offered at this level. In this sense, several SCTP-based mobility schemes have been proposed to provide seamless handoffs through homogeneous and heterogeneous networks. Nevertheless, the proposed solutions suffer from weaknesses such as unnecessary latency and signaling load when mobile users roam inside a same administrative domain. Additionally, the QoS relevant to the disruption time is affected quite considerably by failed Selective Acknowledgment messages (SACKs) and unnecessary chunk retransmissions due to RTO expiration. In this paper, we propose an Enhanced Hierarchical Transport layer Mobility scheme (E-HTM) that reduces handoff latency and improves throughputs observed during the handoff period. Moreover, it introduces a new mobility unit to effect more efficient handoff procedures. Simulation results show that E-HTM guarantees lower handoff latency and good throughput during handovers compared to previous mSCTP-based solutions.