ge Switch). Each IOC consists of a firm- services. ware Message Processor Card and up to nine Device Controller cards, each with four ports. Devices connected to Local Area Networks (LANs) may access 32.18 DMS OA&M the DMS-100 system through Ethernet Interface Units (EIUs). These are housed in peripheral modules called Link Peripheral The maintenance and administration area consists of all the Processors. Input/Output Devices and their controllers used to support the operation and maintenance of the switch. These may include a selection of disk drives, tape drives, printers, terminals, modems, 32.19 Further evolution with DMS PCs and data link controllers. They may be interfaced onto the DMS-Bus either directly via Input Output Controllers (IOC) or via DMS SuperNode architecture is now not only providing a firm Ethernet Interface Units supporting Local Area Networks (LANs). foundation for other switching products to build on, but its enhanced A minimum of two IOC are always provided to guarantee terminal functionality is making advanced features and sophisticated ser- and modem access to the system at all times. vices happen. Furthermore, the Intelligent Network is one step The maintenance and administration workstations on DMS swit- nearer since common channel signalling started using DMS Super- ches are known as MAP, Maintenance and Administration Position- Node based Signal Transfer Points to bring to the domestic sub- S. These consist of a terminal VDU and keyboard (the man machine scriber a type of service previously only available on large private interface), audio visual alarm panel (providing Minor, Major and business exchanges. Critical alarm indications), headset or keyset telephone system (for Structured cabling systems and voice distribution frames Derek Kingaby BTech CEng Reichle De Massari (UK) Ltd (Sections 33.1 - 33.8,33.10-33.11) Graham Hewitt ISICAD (UK) Ltd (Section 33.9) Contents 33.1 Introduction 33/3 33.2 Structured cabling 33/3 33.3 System components 33/4 33.4 Network topology 33/5 Services