Media-Handover-Aware TCP: Preventing Quality Degradation on Co-existing Real-Time Communications

摘要

Multi-homed networks are currently expanding and their access areas are overlapping. The benefit of multi-homed networks is to improve the Quality-of-Service (QoS) of communications through dynamically selecting appropri- ate communications media. Multi-homed networks can im- prove long-term QoS through dynamically switching appro- priate media. However, the instantaneous effect of media switching will degrade short-term QoS. Media handover de- grades the QoS not only of the handover flow itself but also of the flows to be merged. A real-time flow in narrow band- width communications media will particularly be affected by the media handover of a TCP flow with a large win- dow. Therefore, we propose media-handover-aware TCP mechanisms to attain high-quality real-time communica- tions, which adjust the size of the TCP''s transmission win- dow corresponding to the change in bandwidth using a sig- nal to notify of media handover. Through simulations, we evaluated and analyzed our proposed mechanisms.