A high performance ISDN/ATM multimedia integrated access system(THMAS 1) for real time interactive distance learning is proposed in this paper. It consists of remote access units and a central access/switching dev...A high performance ISDN/ATM multimedia integrated access system(THMAS 1) for real time interactive distance learning is proposed in this paper. It consists of remote access units and a central access/switching device. At the subscriber side, the ISDN PRI interface operating at E1 line rate (2.048Mb/s) is provided directly to the termination. When the transmission medium is double of twisted pair cable which has the specification of 0.6mm/22AWG, the longest transmission distance can come to 2.6km. One remote access unit has the capacity of equivalent accessing port of 256 E1s, and the typical capacity for whole THMAS 1 system is 30720 E1 ports. Optical fiber transmission link is adopted between the remote access unit and the central device, and the peak transmission distance under no relay can reach out 60km. To the network direction, a standard ATM UNI interface at STM 1 rate (155.520Mb/s) is designed, so an ISDN/ATM hybrid access system can be constructed. THMAS 1 has the capability of n× 64kb/s (1≤n≤30) ISDN time slots conformance switching, and has the features of small volume, low power consumption, low cost, flexible to reconstructing the network as well as wide coverage of geographical access space. So it is especially suitable for the real time interactive remote teaching.展开更多
本文首先介绍了 ISDN 网络层协议的功能及试验模型的功能块连接,并示出了ISDN 的电路交换呼叫程序.然后,介绍一些 Petri 网的基本概念,利用 Petri 网对TSDN 网络层协议进行模型化,并对模型进行带先进先出(FIFO)信道的可达性分析,得出一...本文首先介绍了 ISDN 网络层协议的功能及试验模型的功能块连接,并示出了ISDN 的电路交换呼叫程序.然后,介绍一些 Petri 网的基本概念,利用 Petri 网对TSDN 网络层协议进行模型化,并对模型进行带先进先出(FIFO)信道的可达性分析,得出一些验证结论.同时,指出该分析方法的一些局限性,并提出一些相应的解决策略.展开更多
文摘A high performance ISDN/ATM multimedia integrated access system(THMAS 1) for real time interactive distance learning is proposed in this paper. It consists of remote access units and a central access/switching device. At the subscriber side, the ISDN PRI interface operating at E1 line rate (2.048Mb/s) is provided directly to the termination. When the transmission medium is double of twisted pair cable which has the specification of 0.6mm/22AWG, the longest transmission distance can come to 2.6km. One remote access unit has the capacity of equivalent accessing port of 256 E1s, and the typical capacity for whole THMAS 1 system is 30720 E1 ports. Optical fiber transmission link is adopted between the remote access unit and the central device, and the peak transmission distance under no relay can reach out 60km. To the network direction, a standard ATM UNI interface at STM 1 rate (155.520Mb/s) is designed, so an ISDN/ATM hybrid access system can be constructed. THMAS 1 has the capability of n× 64kb/s (1≤n≤30) ISDN time slots conformance switching, and has the features of small volume, low power consumption, low cost, flexible to reconstructing the network as well as wide coverage of geographical access space. So it is especially suitable for the real time interactive remote teaching.
文摘本文首先介绍了 ISDN 网络层协议的功能及试验模型的功能块连接,并示出了ISDN 的电路交换呼叫程序.然后,介绍一些 Petri 网的基本概念,利用 Petri 网对TSDN 网络层协议进行模型化,并对模型进行带先进先出(FIFO)信道的可达性分析,得出一些验证结论.同时,指出该分析方法的一些局限性,并提出一些相应的解决策略.
