一种光通信系统可用度计算方法

Availability of fiber optic systems

为了研究光纤通信系统无中断工作的能力 ,计算通信系统可用度具有重要的意义。在 ITU- T G.911光通信系统可用度计算的基本原则下 ,建立了系统状态的 Markov模型和状态转移概率矩阵 ,并利用稳态 Markov模型中状态转移概率平衡的特点求解稳态概率。再利用网络拓扑结构和保护机制的信息 ,通过简单的概率运算得到系统的稳态可用度。在这种计算方法的基础上分析了 SDH的自愈保护机制以及各种故障对系统可用性的影响。在计算结果的指导下 ,可以知道为了达到特定的可用度 。

To study the communication systems capability of working without interrupt, calculating the communication systems availability has great importance. This paper reviews the basic concept of communication systems availability. The Markov model and the matrix of the state transfer probability of the system is presented for the ITU T G.911 rules. The steady state equations are presented for the properties of the Markov model. The steady state probability of each state can be easily obtained with these equations. The algorithm uses the equation results, the topology and the communication system protective scheme to calculate the availability. Finally, this paper analyzes the availability of the synchronized digital hierarchy (SDH) self healing ring and the influence of the protective scheme. The effects of failures of the network elements and the fibers on the system are also considered. With the results of this algorithm, the time of the communication equipments and the fibers in the good condition and the time needed for repairing the broken down equipments and fibers can be obtained.