增强移动计算机网络端-端通信可靠性

通过改善移动台和基站之间网络层通信的可靠性，便能有效增强移动计算机网络端－端通信的性能。当网络层提供数据服务时，本文给出了移动台和基站之间的可靠数据报协议，该协议保证数据报的无丢失传递，但不必保证其顺序。当移动台在不同基站间切换时，新旧基站之间通过镜像操作，并在新旧路由之间进行流量控制，使移动台可靠数据报或虚电路协议仍能继续运行，保证了端－端通信的可靠性。可靠数据报协中直接嵌入在传统数据报下面，传

ENHANCEMENT OF END-TO-END COMMUNICATION DEPENDABILITY OF MOBILE COMPUTER NETWORK

This paper studies the end-to-end communication dependability of mobile computer network, and improves it by enhancing the network layer dependability between mobile computer and base station. For a network providing datagram service, this paper gives a dependable datagram protocol, which is located between the existing datagram and wireless link protocols, and used mainly in mobile host and base station. It delivers packet without loss, but does not guarantee packet'sorder. It is simple to implement, requires a little resource, and introduces little overhead and delay, When the mobile computer is handovering between two base stations, by making the new base station mirror the old base station and utilizng flow control between new and old routes, the network layer protocol (dependable datagram or virtual circuit) in mobile computer can still work, thus guaranteeing the end-to-end communication dependability. The dependable datagram protocol can be easily and fast mirrored by the new base station. For a network providing virtual circuit service, the mirroring of virtual circuit is more cornplicated, the residual packets in the old virtual circuit branch must be transferred into the new virtual circuit branch orderly. The connection re-establishment procedures for the uplink and downlink are given. The end-to-end performance of mobile network can be greatly improved.