摘要
在TCP、HDLC等能提供可靠通信服务的通信协议中,需要使用定时器来对数据包的超时重发进行计时。由于在发送窗口的范围内可发送多个数据包,所以需要使用多个独立的定时器。在协议实现时,如果直接利用操作系统或硬件实现多个定时器的功能,不仅受到诸多限制,而且浪费资源。本文介绍了一种用单个定时器模拟实现多个定时器的方案,该方案以数据链路层ARQ协议模型为基础,经过修改可以很容易地应用于各种通信协议。
In reliable protocols such as TCP and HDLC, a timer is required to timing for data package overtime retransmission. As multiple packages can be transmitted within the transmit window, multiple standalone timers are required. During protocol realization, it is restricted and resource wasting that asking the operating system or hardware to provide multiple timers directly. This per introduces a method for realize multiple timers by using a single timer. It is based on the ARQ protocol model of data link layer, and can be used after modification in some protocols.
出处
《计算机与现代化》
2008年第12期121-123,127,共4页
Computer and Modernization
关键词
超时重发
多定时器
ARQ协议
overtime retransmission
multiple timers
ARQ protocol
