The combination of BGW and the MAP works as a MAP of the Hierarchical Mobile IPv6 . The BGW will get the information about the MN position and directly send the packets to MN . So solve the problem about route optimization and node congestion .
并且使得边界网关了解移动节点的位置信息，直接将数据包送到移动节点，实现路由优化并解决了MAP的拥塞问题。
bgw