LAN上实现ISDN应用的设计

DESIGN OF THE IMPLEMENTATION OF ISDN SERVICES ON LAN

综合业务数字网(ISDN)是未来一体化的通用网络。为使现有局域网(LAN)适配于ISDN,文中提出利用LAN的传输能力在LAN上实现ISDN功能,从而达到LAN工作站与ISDN间业务的完全互通。在LAN上实现ISDN功能的方案是:1)开发在工作站上与LAN应用软件并发运行的综合业务应用软件,这些软件应按ISDN的业务控制方式实现,以便能与ISDN直接互通;2)在LAN上增加综合业务传输接口,该接口不同于LAN软件提供的接口,具有实时性,而且该接口的设计应使LAN应用与综合业务应用间互相独立;3)设计至公用ISDN的网关,在网关支持下不但可使LAN工作站作为ISDN的用户终端,还可在ISDN承载业务支持下扩大LAN应用的通达范围。初步试验表明,这种方案是可行的。

The integrated services digital network (ISDN) will be the global universal network. The author thinks that the direct way to match a LAN with ISDN is to realize in LAN all services of ISDN. The design of the strategy includes: 1) Adding a concurrent integrated services software on LAN stations, which is an implementation of ISDN services and is interoperable with ISDN services. 2) Adding a real - time transmission interface into LAN protocol layers,which is characterized by the independence of the execution and of the evolution. 3)A gateway is suggested, so as to utilize public ISDNs' services on LAN stations, and to expand the geographical area of LANs. The paper discusses issues in designing and implementing in detail. A preliminary trial shows the feasiblity of the strategy.