| 2. | It can be divided logically and vertically into four layers : network element management layer , network management layer , service management layer and business management layer , each pair of adjacent layers accord with manager / agent logical pattern 采用软件复用思想,针对表现层、设备层、数据库层分别进行了通用性设计;并对设计模式在本系统中的应用做了研究。 |