Date Added: Apr 2012
Although a variety of wireless interfaces are available on mobile devices, they still provide only low throughput so far. When coverage areas of those different technologies overlap, mobile devices with multiple interfaces can use them simultaneously by mechanism of Bandwidth Aggregation. However, there are some performance problems for Bandwidth Aggregation on Network Layer and lower Layer which derive from TCP congestion control mechanism. If Bandwidth Aggregation is performed at a layer lower than Transport layer, a packet loss happened in one route should decrease performance of all routes because reducing TCP congestion window on such a case affects communications of all routes.