r ATM devices. 21.10.2 ILMI Service Interface The ILMI uses SNMP for monitoring and control operations of ATM management infor- mation across the UNI. The ATM UNI management information will be represented in a management information base (MIB). The types of management information will be available in the ATM UNI MIB are as follows: REVIEW EXERCISES ATM UNI ILMI MIB Physical Virtual Virtual Network Address Layer Layer Channel Layer Prefix Connection Connection Statistics Common Specific Interface Interface Interface Interface Interface Interface Interface Index Index Index + Index + Index Index + Index + VPI + VCI Prefix Address Figure 21.17 ILMI ATM UNI MIB tree structure. (From ATM Forum, Figure 4-3, page 111, Ref. 7.) Virtual path (VP) connections Virtual channel (VC) connections Address registration information The tree structure of the ATM UNI ILMI MIB is shown in Figure 21.17. REVIEW EXERCISES 1. Give at least four major benefits to the network operator derived by implementing a network management system. Name the five traditional tasks of network management. Discuss fault management and describe some of the capability it should incorporate. It has been said that a network management center is the front-line command post for networks Give the four steps involved in finding a "fault" in a telecommunication network. 6. Describe how a well-engineered network management system can often cut the time almost to zero for isolating faults. A network management system should be built around on-line monitoring systems that are nonintrusive and that are found in (list such systems). 8. Explain how BERT works. 9. Network management systems require communications, especially to/from the net- work management center and remote equipment. Discuss concerns you might have with such systems, particularly if they share revenue-traffic-bearing channels. 10. From a PSTN perspective, network management may be called "surveillance and control." What are the two major objectives of surveillance and control? NETWORK MANAGEMENT 11. D