Managing The New Network

A critical guide for network architects and administrators and the people who manage them.

• By Greg Neilson
• 05/01/2000

Directory Enabled Networks (DEN) is the standards-based paradigm shift that eventually will take us from networks of individually configured devices to an intelligent grouping that can manage all of the devices in the network. Network architects will be able to define policies for handling traffic without having to configure specific parameters on every intermediate network device to produce desired results.

Directory Enabled Networks, the book, is co-written by someone uniquely positioned to describe the inner workings of DEN, since the author originated the concept of DEN, sits on multiple related standards working groups, and is driving the usage of DEN within Cisco.

DEN is still in its early days of implementation, and the first products are now seeing the light of day. So don't be thinking that you'll be able to read this tome tonight and design and implement a new directory-enabled network for your company tomorrow. The focus of the book is to explain what DEN is and isn't and then cover the main concepts needed to be proficient with the technology-object modeling, directories, and network management via policies. Then the various object models are presented and some conclusions made about where exactly this technology stands today.

Part 1 offers an overview of DEN and object-oriented modeling and then revisits the motivation for the development of DEN in being able to provide an intelligent network.

Part 2 is the core of the book. It describes in great detail the Common Information Model, CIM, which is used to describe how a system is managed, DEN's physical model, the CIM/DEN logical network model, and finally DEN's policy model.

Part 3 of the book discusses how policy-based networking can be used in practice and what the various vendors are doing about DEN. It closes with an update of where the relevant working groups are headed and what this means for the future of DEN.

There's no doubt that is the authoritative work on DEN at the moment. But should you consider this book? If you're a network architect (or want to be one), then you'll need to get a solid handle on this technology. Similarly, if you see yourself specializing in Windows 2000 Active Directory design, you would do well to understand what's happening with this networking technology, since you'll share common interests in defining user access to network resources. And, of course, Cisco's Network Services for Active Directory (CSN/AD) support will build upon Active Directory in being able to provide policy-based network management.

IT managers will probably need an overview of this technology in order to communicate sensibly with their technical staff members, and there are three chapters ("The DEN Value Proposition, " "Motivation for DEN," and "Policy-Based Networking") that will give them the understanding they need for the future without drowning them in unnecessary jargon.