编程实现简单可靠的数据传输GBN协议，模拟可靠数据传输，理解TCP协议可靠传输的差错检测、重传、累计确认、定时器的可靠传输策略-Programming is simple and reliable data transfer GBN protocol, simulation and reliable data transfer, reliable transfer of understanding of the TCP protocol error detection, retransmission, the cumulative confirmed timer reliable transmission strategy