Communications system, carrier-side communication apparatus, base station apparatus, and communication method therefor

摘要

In a communications system, a first upper node performs communication through a first communication session, and a second upper node performs communication through a second communication session. An upper communication control unit controls those upper nodes. A first communication unit communicates with the first upper node through the first communication session established therewith. A second communication unit communicates with the second upper node through the second communication session established therewith. A communication control unit controls those communication units. The communication control unit and the upper communication control unit perform communication path switching so as to use the second communication session to transport a signal intended for the first communication session, when the first communication sessions is disrupted, or when the number of existing first communication sessions has reached an upper limit that the first upper node can handle.