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horizon.GIF (9417 bytes)
July 1999


STANDARDS-BASED MANAGEMENT FOR CONVERGED NETWORKS

BY BROUGH TURNER

Historically, administration and management of telecom equipment was proprietary. Each PBX had its own approach: the Bell System built a large set of standards, but only for their internal use. The past twenty years have seen the breakup of the Bell System and an explosion in the telecom equipment business. But, except for the emergence of an ITU standard called TMN (Telecommunications Management Networks), management of telecom equipment and telecom networks has remained a highly specialized field with mostly proprietary approaches.

In data communications the story is dramatically better. Here a single protocol, SNMP (Simple Network Management Protocol), has emerged as the standard for managing anything that is part of the Internet. And, with the telecom market waking up to the Internet, SNMP is making inroads into the telecom equipment industry. Other Internet standards- notably one called RADIUS- handle authentication, for example when you log onto an ISP. Meanwhile, MIS directors need to manage zillions of PCs is driving a new class of management applications.

In fact, enterprise management is driving developments far beyond SNMP and RADIUS. The field of enterprise management includes desktop PCs, LAN equipment, WAN access equipment, connections, services and service policies (grades of service), plus servers, and someday soon corporate telecommunications. And the direction for managing this all-encompassing network is being determined by developments in the world of computers - PCs - moreso than by developments in the Internet world or the IETF.

CURRENT NETWORK MANAGEMENT
Most equipment in the Internet, as well as the equipment in the core of most enterprise networks, is managed using SNMP. Each managed device contains one or more MIBs (management information bases) that define device-related information, plus SNMP agents, that is, software that can take information from an MIB and publish it over the network. These components allow central management software to interrogate each device and retrieve information.

Unfortunately, SNMP v.1 — the current standard — has inadequate security. As a result, SNMP is used only to report statistics such as how many packets a router has dropped, what the current routes are, what the traffic levels are, or whether its T1 trunks are in red alarm mode. Re-configuration via SNMP would not be safe. It may not be desirable for hackers to discover how much traffic a router is handling, but it is completely unacceptable if they can break into the router and change its configuration or turn off specific ports. So, configuration changes are typically accomplished by other means, like a Telnet session with a proprietary command line interface. While management system software may make this transparent to the network administrator, the interface is specific to each device and proprietary with each vendor.

Efforts to enhance SNMP have been underway for years. SNMP v.2 was completed several years ago but, due to continuing security issues, was not widely adopted. Recently, an IETF working group completed SNMP v.3 as a set of draft standards. This version addresses security issues, and the Internet community is hopeful that it will provide a way to not only monitor network devices, but also administer and configure them.

AN UNEXPECTED FORCE
But an interesting initiative from the PC world may actually supercede SNMP v.3, at least in the enterprise, before v.3 is widely deployed. WBEM (Web-Based Enterprise Management) is emerging as a likely solution to the problem of managing PCs in an enterprise and, in fact, managing the converged enterprise network. Until now, MIS directors have had a limited set of tools for administering their PC infrastructure. Indeed, in most cases, it is still necessary to send support personnel to individual offices to maintain equipment. But big changes are finally at hand.

Some years ago, Microsoft got serious about PC administration and management, perhaps in response to requests from MIS directors, or perhaps more specifically in response to the threat of the “Network Computer.” In any event, in 1996 Microsoft contributed a large body of work to what is now the Distributed Management Task Force (DMTF) and, jointly with Cisco, Compaq, Intel, and BMC software, announced an initiative called Web-Based Enterprise Management. In 1998, the WBEM initiative was also transferred to the DMTF.

The first thing that the WBEM/ DMTF initiative did was to define an object-oriented information model — a way to describe any kind of manageable entity. This is called the Common Information Model (CIM). CIM fills the same function as MIBs in an SNMP system, but CIM is a significant improvement over MIBs.

The MIB hierarchy is flat and has only had to support SNMP, which in turn has been limited to manager-to-agent polling and simple data sampling. CIM is extensible and can structure large amounts of complex data. And CIM is object-oriented. This makes it faster and easier to build management solutions by normalizing diverse devices through a concept called inheritance. A “core” schema defines general characteristics of any manageable entity — information that will be inherited by all devices. Then a set of “common” schemas define information models for the concepts and functionality needed for manageable entities in five broad areas — the system, device, application, network and physical schema. Finally, “extension” schemas model specific platforms, protocols, or corporate brands.

Perhaps CIM’s most important feature is its ability to show the relationships between different components in an enterprise network. Using CIM, “You can see this computer is associated with this application, that is running services that are out on this server,” says Winston Bumpus, DMTF president and Novell’s corporate architect.

WBEM goes on to define transport mechanisms and interfaces to support information sharing between software products. As the name implies, WBEM can support browser access to data, but other interfaces support integration with most existing system and network management technologies. Not surprisingly for a technology that originated with Microsoft, WBEM takes the “embrace and extend” approach. WBEM can completely wrap existing SNMP-based equipment, and WBEM systems can export information to SNMP management systems.

It is clear that Microsoft is the most visible force behind WBEM. In fact, even as I write this, if you go to the DMTF web site and look at the WBEM tutorial, it’s in Microsoft Help File format. This means it can only be read with Internet Explorer, and not with Netscape Navigator — not very friendly for an impartial industry consortium! On the other hand, CIM is elegant, and WBEM is eminently suitable to the tasks of enterprise management.

WBEM has endorsement and active support not just from Microsoft, but also from Cisco, Intel, and Compaq and the major vendors of management applications like HP and IBM/Tivoli. And, there is major Unix support expected, which will probably be public by the time you read this. So we are certain to see a wide variety of devices supporting WBEM/CIM.

It’s unlikely WBEM will overwhelm SNMP in the near term — you will see SNMP support in routers and switches for years to come — but it is equally clear that WBEM is the way PCs will be administered in the enterprise. With WBEM support in Windows 98 and the latest versions of Windows NT 4 (since Service Pack 4) and CIM support in a variety of other contexts, expect widespread WBEM deployments over the next two years.

DIRECTORY-ENABLED NETWORKS
The next evolution in management capabilities will be directory-enabled networks (DENs). Here again, the DMTF is the focus of the action. Increasingly, MIS directors and ISPs have been looking at enterprise directories such at Novell’s Netware Directory Services or Netscape’s Directory Server as a way to get control of the information needed to administer users, addresses, and access rights across a network. The problem is that modern corporations can have dozens or even hundreds of separate directories and user databases with separate IDs and passwords for separate purposes.

The DEN initiative was a response from Microsoft and Cisco that promised to leverage Microsoft’s forthcoming Active Directory to solve the same problem. Of course, Active Directory was vaporware while Novell and Netscape had products. Luckily, this initiative was also turned over to the DMTF, and Novell and a wide range of additional companies are participating. The DEN initiative uses the same CIM information model that is fundamental to WBEM.

Once widely deployed, mostly likely within 2–3 years, DENs will support a new class of networked applications where users can access identical services no matter where they are: at home, at the office, or on the road. However, the promise of DEN is not just information sharing among diverse directories, but also more automated management of devices. If a user can connect to a network at any location and have their desktop appear as they last left it, then we can also envision plugging in a replacement piece of equipment, identifying it once, and having the rest of its installation and configuration completed automatically.

BEYOND DEVICE MANAGEMENT
Management issues, however, go beyond administering routers and switches in the network or PCs on the desktop. With the converged network, another kind of management is required: “policy management.”

The need for policy management can best be illustrated through an example. ATM networks can provide quality of service (QoS) guarantees, an invaluable capability for enabling high-quality voice and video services, but it has created a need to allocate and administer the higher quality services. Who gets to use them and with what priority? Is an individual user allowed to tie up 2 Mbps of bandwidth for a video conference every Friday morning, or only 384 Kbps?

These are “policy” questions. And with the advent of QoS initiatives for IP, such as RSVP and DiffServ, the IETF is also faced with policy management issues. These are being addressed in the IETF’s Policy Framework working group set up last year. Their goal is to “provide a framework that can represent, manage, and share policies and policy information in a vendor-independent, interoperable, and scalable manner.”

Interestingly, this IETF working group is using CIM as their information model! So the WBEM initiative is already beginning to have an impact on the Internet.

A CHANGING MANAGEMENT LANDSCAPE
Network management and enterprise facilities management are both entering a period of great change. Standards-based management systems are expanding from routers and switches to the desktop. And object-oriented technology developed for the desktop PC is coming back to add to and improve the Internet. As we move to a converged network, this will greatly benefit telecommunications. At a minimum, your corporate telephone directory should be a seamless part of the rest of your MIS infrastructure. In time, we should see the same open systems benefits that are driving progress in enterprise management systems begin to affect even the mostly proprietary world of corporate telecommunications.

Brough Turner is senior vice president of technology at Natural MicroSystems, a leading provider of hardware and software technologies for developers of high-value telecommunications solutions. For more information, call Natural MicroSystems at 508-620-9300, or visit the company’s Web site at www.nmss.com. E-mail to the author is also welcome.







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