Handbook of Local Area Networks, 1998 Edition:LAN Management Click Here! Search the site:   ITLibrary ITKnowledge EXPERT SEARCH Programming Languages Databases Security Web Services Network Services Middleware Components Operating Systems User Interfaces Groupware & Collaboration Content Management Productivity Applications Hardware Fun & Games EarthWeb sites Crossnodes Datamation Developer.com DICE EarthWeb.com EarthWeb Direct ERP Hub Gamelan GoCertify.com HTMLGoodies Intranet Journal IT Knowledge IT Library JavaGoodies JARS JavaScripts.com open source IT RoadCoders Y2K Info Previous Table of Contents Next 7-2Managing Switched Internetworks BILL ERDMAN Recent improvements in networking technologies have resulted in great changes in the way computers are connected, managed, and used. The desktop-centric computing models of the 1980s and early 1990s are giving way to a new information model in which the network is the primary technical resource. Desktop computers, workgroup servers, and host CPUs remain effective for information storage and processing. But the lifeblood of the information system is the network itself. VIRTUAL LANS Many organizations are facing tremendous growing pains as they seek to upgrade their low-bandwidth, shared-media networks to accommodate more complex information requirements. Users are increasingly sending compound documents and large graphics files across the network, and LAN administrators wrestle with the new demands brought on by multimedia, client/server, and Internet browsing applications. The industry is experiencing a subtle yet pervasive paradigm shift as networks evolve from a hub-router model into a switch-router model and customers begin using new technologies such as Fast Ethernet switching and asynchronous transfer mode (ATM). Switches not only increase performance by an order of magnitude over traditional shared hubs, they offer greater intelligence per port and new functionality not previously available such as dedicated bandwidth and virtual LANs (VLANs). An intelligent port also allows more options for port grouping, security, filtering, broadcast suppression, and other important tasks. All of these functions lend themselves to greater management and configuration options. The new multilayer switching architectures that are emerging offer the proven advantages of routing intelligence, the high performance of switches, and the flexibility to accommodate a frequent reorganization of users and devices. In most cases, these architectures are built around the highly flexible concept of the switched internetwork. Switched internetworks integrate various types of switching devices into existing shared-media hub and collapsed backbone router networks to optimize the benefits of both routing and switching. But although LAN and ATM switches provide great performance improvements, they also raise new challenges for network managers. Managing a switch-based network is radically different from managing a traditional hub/router-based network. Ideally, network managers need the following: •  Tools that can intelligently discover the network and comprehensively understand the physical infrastructure of switches, routers, and hubs. •  The ability to generate an autotopology layout with multilayer views of the physical, logical, and network relationships. •  Graphical utilities to query the topology maps, allowing users to view and configure logically defined workgroups. •  Automated interswitched link assignment settings to simplify VLAN management. •  Support for remote monitoring (RMON) to facilitate the task of monitoring traffic analysis capabilities, particularly the high-bandwidth, low-latency applications becoming prevalent with multimedia applications. •  Consistent reporting and auditing functions integrated through an easy-to-use graphical console. •  Intelligent agents embedded in the multilayer switches for reducing management traffic and reducing reliance on centralized management platforms. •  Expert design and analysis systems for optimizing network connectivity and communications. •  Creation, monitoring, and troubleshooting of virtual circuits between ATM switches and routers. Management tools for switched internetworks should be built on a strong base provided by the their applications and a proven, comprehensive set of tools for managing routed networks, as shown in Exhibit 7-2-1. Switch management applications should add capabilities for managing internetwork traffic, monitoring internetwork performance, maintaining VLANs, and configuring switches and other network devices. Exhibit 7-2-1.  Switched Internetworking Management Model SWITCHED INTERNETWORK MANAGEMENT A switched internetwork is more than just a collection of devices. It is a cohesive information system supported by an intelligent software infrastructure. Older hub management tools are not designed for VLANs and switched internetworks. In many cases, switches are a black box to network probes and other management tools, making it difficult to discern traffic patterns and troubleshoot problems. Many vendors have a strategy for network management, a plan for combining new networks with old, and a plan for migrating to ATM. A network management strategy should be a cohesive set of applications and internetwork operating system software. It should include products for VLAN management, traffic analysis, internetwork planning, link management, ATM management, and multilayer topology mapping. An efficient network management strategy includes GUI-based applications and an embedded layer of software intelligence common to all elements of a network — its devices, links, and configuration. Such a strategy helps administrators manage their switched internetwork platforms and VLANs in an effective, comprehensive way. Previous Table of Contents Next Use of this site is subject certain Terms & Conditions. Copyright (c) 1996-1999 EarthWeb, Inc.. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of EarthWeb is prohibited. 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