The loss at 1550nm shall not increase by Mode field diameter = In range 9mm to 10mm at 1300nm more than 1dB when measured on 100 turns of fibre loose wound Mode field concentricity error less than 1.0um (up to 3.0um may on a 75mm diameter mandrel. be appropriate for some jointing techniques and joint loss require- ments). This page intentionally left blank Network management Fraidoon Mazda MPhil DFH DMS MBIM CEng FIEE Northern Telecom Contents 16.1 The need for network management 16/3 16.2 Network management structure 16/3 16.3 Network management hierarchy 16/4 16.4 Network management functions 16/5 16.5 Trends in network management 16/6 The OSI model 16/7 16.7 OSI network management concepts 16/11 16.8 The Telecommunication Management Network 16/14 16.9 The Simple Network Management Protocol 16/19 16.10 Bibliography 16/24 This page intentionally left blank The need for network management 16/3 The need for network management Network management structure Network management has traditionally been the last item to be The elements within a network manager can be conveniently con- planned when designing a new network, whilst it should always be sidered to be structured into four sections or layers, as in Figure the first. A system which can provide interconnectivity and data 16.2. At the lowest level is the platform on which the manager runs. interchange may be thought of as having met its objectives, but if it cannot be managed then it will soon prove to be worthless. The function of a network is to satisfy the needs of the business FUNCTIONALITY that it serves, and it is only through effective network management that one can ensure that these aims are being met. Figure 16.1 shows the wide variety of network combinations within which network management has to operate. Networks can be HIERARCHY privately owned, either leased from a public operator or be fully private, such as the vast optical infrastructure of the utility com- panies. The transmission media can be copper, optical or radio INTERFACE based, for example 