在DECnet数据链路级开发实时通讯程序

DEVELOPING REAL-TIME NETWORK COMMUNICATION PROGRAM AT DECnet DATA LINK LEVEL

虽然DECnet在应用层提供任务—任务通讯功能,但由于网络软件各层的开销,数据传输率往往不能满足实时应用的要求。本文介绍在VAX系列机上利用DECnet-VAX的以太网驱动器的正常QIO和内部QIO接口直接在数据链路级上开发实时通讯程序。实验表明,数据链路级的数据传输率比应用层任务通讯的数据传输率提高5倍左右。

We can develope network task-task communication programs using DECnet application level interface, but the data transfer rate can't meet the requirements of many real-time applications due to the high-layer network software overhead. In this paper we describe the way of developing data-link level task-task communication programs using VAX ETHERnet driver' s QIO and internal QIO interfaces. It' s showed that the data transfer rate can be improved by more than 5 times.