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 7-3Managing Networks with the Global Naming Tree GILBERT HELD Tree structures are a common method for accessing information. The reason for the use of a tree structure is that the path from the root via one or more branches to a leaf provides a unique method for addressing information stored at the end of the path. The most common use of a tree structure inverts the tree, placing the root at the top. From the root, one or more branches flow downward and separate into sub-branches. This subdivision can theoretically continue indefinitely, with the major restriction being the number of characters, digits, or identifiers that can be used to define a path through the tree. The most commonly used tree structure employed in computer-based systems provides data management in the form of a directory structure. When used to manage data within a directory structure, the root of the tree represents the top of the directory, while subdirectories represent branches under the root. Another common tree structure is employed by data base management systems. The International Standards Organization (ISO) and the International Telecommunications Union-Telecommunications Standardization Sector (ITU-TSS) have jointly developed a tree-based structure for assigning unique identifiers to different types of objects. That tree is known as a global naming tree. STRUCTURE OF THE GLOBAL NAMING TREE Objects in the global naming tree can represent any type of information. In addition, the tree structure makes it possible for network managers to delegate responsibility for information structuring to other organizations under different nodes within the global naming tree. Use in Network Management Applications Exhibit 7-3-1 illustrates the basic structure of the global naming tree that is oriented toward its use in network management applications. Under the root are three top-level nodes. Exhibit 7-3-1.  The Network Management Portion of the Global Naming Tree As Exhibit 7-3-1 shows, each node in the tree has both a label and a numeric identifier. The top-level nodes indicate the organization that administers the subtree under the node. The three top-level nodes allow the ITU, ISO, and the ISO and ITU jointly to administer distinct portions of the global naming tree. The third node (Org) under the ISO node was defined as a mechanism to delegate authority to other organizations. One of those organizations is the US Department of Defense (DOD), which is the sixth node under the Org node. Because the US Department of Defense initially funded the Advanced Research Projects Agency network (ARPAnet), which is considered as the predecessor to the Internet, and still provides a degree of administrative and operational support for certain Internet activities, the first node under the DOD node is the Internet node. The Internet node and the subtree residing under it is owned by the Internet Activities Board (IAB) and administered by the Internet Assigned Numbers Authority (IANA). The IANA is responsible for maintaining a document of assigned numbers, which tracks the complete set of parameters used in the Transmission Control Protocol/Internet protocol (TCP/IP) suite to include addresses in the Internet subtree that identify simple network management protocol (SNMP) and remote monitoring (RMON) objects. Organizations that wish to develop extensions to SNMP and RMON standard objects are assigned distinct identifiers within the Internet subtree. The Internet Subtree Currently, six nodes are defined under the Internet node — directory, management, experimental, private, security, and SNMPV2. Two of those nodes, security and SNMPV2, are being standardized and may not be completely defined for a few years. The experimental node provides a location for the placement of newly developed and unproved objects. After a trial period, objects deemed to be useful are then moved to a standardized location under the management subtree. That tree (Mgmt) is used to hold all standardized network management variables and represents the portion of the global naming tree most network management systems are designed to work with. The private subtree represents a location where equipment vendors, software developers, universities, and government agencies can develop extensions to SNMP. To do so, an organization is assigned a node under private/enterprises that represents an assigned subtree within the global naming tree. Within that subtree, an organization is free to define its own structure for product identifiers and management information base (MIB) object definitions that are required to manage a specific product or group of products. Because it is almost impossible for any one network management product to be aware of every vendor-specific set of managed objects located under the private/enterprise node, the use of these path identifiers gives network managers and administrators a way to “walk through” the global naming tree structure, so they can set or retrieve information from any vendor subtree. This is a capability network managers might not otherwise obtain by relying on the standard features of a network management system. 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. Please read our privacy policy for details.