Preface


The last two decades have been dominated by distinct patterns of computer use. The 1980s saw wide-scale deployment of PC- and microprocessor-based technology. The 1990s saw this infrastructure becoming internetworked, connected to the Internet, and increasingly embracing client/server technology. Initially, clients were heavy duty (or fat) and communicated with local servers, but by the end of the 1990s clients had become thin and servers were increasingly distributed. The first decade of the 21st century may well be one of global system (as well as network) integration and management during which we will see previously disparate networks and systems interconnected for new purposes. Nowhere is this more apparent than in the area of telecommunications and data networking.

The relentless growth and extended reach of both enterprise and service provider (SP) networks have been accompanied by an increased demand for advanced vendor-independent network management software tools. This is particularly the case as enterprises leverage their network investments by deploying evermore advanced, mission-critical systems like voice-over-IP and desktop video conferencing applications [ATM&IP2001]. At the same time, service providers are consolidating and deploying Multiprotocol Label Switching (MPLS) cores and IP services, such as IP VPNs, as part of their migration path to an end-to-end packet-based infrastructure [Alcatel2001].

In many ways the managers of enterprise networks face a daunting task because of the sheer diversity of network elements (NE) and systems ”multi-vendor routers, switches, leased lines, WANs, VLANs, Storage Area Networks (SANs), mobile and desktop telephony, PABXs, soft switches [Sweeney2001], databases, a wide range of software applications, NT/Windows 2000/Unix servers, minicomputers, mainframes, and so on. These systems are the data lifeblood of modern corporations, and their continuous availability is crucial. Unfortunately, most of these enterprise NEs have their own proprietary management tools, which have to be learned and maintained over time, adding to the cost of ownership. Proprietary systems (a bad thing) and centralized, automated management (a good thing) are, in general, mutually exclusive.

Enterprises have a lot of legacy systems and equipment, which must be depreciated over many years . Forklift upgrades (getting rid of all the old stuff and putting in the latest) are generally too expensive, so system and network management skill sets must be present throughout the lifecycle. This means that enterprises will continue to be a highly complex network management proposition for a long time to come. Complex management equates to high operational cost. This book proposes that all network-based systems produced for the enterprise market should:

  • Provide MIB module files that describe the principal managed objects.

  • Conform to or extend standard MIBs.

  • Provide any proprietary MIBs in text file or downloadable form at the time of purchase.

  • Guarantee as far as possible that the management facilities will be available during periods of high traffic or even congestion.

  • Include high-performance agents that can issue useful notifications and execute both read and write operations against their MIBs.

  • Deploy SNMPv3 agents (entities).

  • Provide simple scripts for reading from and writing to their MIBs.

  • Provide snap-in modules (Java/C++) to allow easy integration with existing network management systems.

  • Support automation via SNMP of routine administrative tasks such as adding users to a VLAN or disks to a SAN.

Network managers should insist on these minimum requirements before making purchasing decisions. On the supply side of the industry, vendors should from day one build standards-based (SNMPv3) management facilities into their networking products. Many vendors leave the management infrastructure (agents, MIBs, etc.) development until quite late in the development cycle. This can result in poor-quality agents and MIBs, ultimately reducing the manageability of the NEs and the wider network.

Several equipment vendors have a large number of different element management systems (EMS) to manage just their own equipment. Since the EMS often forms the basis for the NMS, this multiplicity of different EMS can make NMS software harder to develop, particularly in multivendor networks. A single EMS across all NEs is a better proposition.

Another major theme of this book is the migration of networks toward a layer 3 model based on the IP protocol. This is a mega-trend affecting pretty much any industry involved in moving data from one networked location to another. Management systems for layer 3- converged (voice, video, and data) networks are an increasingly important issue. We use MPLS as a running example of how networks are evolving in terms of providing quality of service, traffic engineering, and so on.



Network Management, MIBs and MPLS
Network Management, MIBs and MPLS: Principles, Design and Implementation
ISBN: 0131011138
EAN: 2147483647
Year: 2003
Pages: 150

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