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 The second address is the set of addresses within the global naming tree that defines the location of counters, registers, and memory locations that the administrator may be able to read from, write into, or read and write, depending on the access method defined for the object. By having a standard method for defining objects in the global naming tree, different vendors can independently develop managed objects, avoiding the potential for the occurrence of addressing conflicts. In addition, vendors can design their products to support applicable SNMP and RMON groups in a standardized manner, and other vendors can develop network management systems without having to know full details of different vendor products. In short, if a network management system supports the global naming tree structure, any user who understand tree addressing concepts is able to read, write, or read and write to and from different managed devices manufactured by different vendors. SAMPLE APPLICATION USING SAMPLE TOOL For purposes of further illustrating the use of the global naming tree in network management operations, this section uses the example of an application developed using SimpleView from Triticom (Eden Prairie MN). To use this program to manage an object, the user must first select the object. The screen shot in Exhibit 7-3-2 shows that the Ethernet probe at IP address 198.78.46.41 was selected. Exhibit 7-3-3 represents the values of object identifiers in the system group of the Ethernet probe. This system group contains seven object identifiers. Exhibit 7-3-2.  Sample of SimpleView Screen Exhibit 7-3-3.  The System Group Tools such as SimpleView allow a network administrator to retrieve basic SNMP or RMON information. Because there are more than 1,000 vendors that are assigned subtrees under the private enterprises node in the global naming tree (which would make their support difficult, if not impossible, to accomplish via a menu that identifies the name of each object identifier), the sample tool uses a series of SNMP commands to access information in managed objects developed by different vendors. The Get, Get Next, and Set entries shown in the Manage menu in Exhibit 7-3-2 represent three SNMP commands. The Get command is used to request the values of one or more MIB variables. The Get Next command is used to read values sequentially. By selecting the Get Next command, the user can either go directly to a specific tree address (by typing in the address) or, if they do not know the address, browse predefined portions of the global naming tree that locate commonly used objects. The third SNMP command supported, the Set command, allows the network administrator to update one or more MIB values. Once a command is executed, SimpleView displays the results in the program's Trap Log. Exhibit 7-3-4 shows an entry that occurred as a result of the execution of the Get Next command using a tree address to retrieve the value of the sysUpTime object. Although the time is displayed in hundredths of a second, such tools can also convert that time into days, hours, minutes, and seconds. By issuing several Get Next Commands, the values for sysContact and sysName and subsequent objects in the group would also be displayed in the Trap Log. Thus, once the user knows an address they can walk through a path using a series of Get Next commands to retrieve subsequent object values. Exhibit 7-3-4.  SimpleView Trap Log Window SUMMARY The global naming tree provides a mechanism for labeling and identifying objects while eliminating the possibility of addressing conflicts. By understanding how to use path addresses in conjunction with object identifier information, network administrators can manage any device that complies with the global naming tree method for identifying objects. The easiest way to retrieve information from proprietary products developed to comply with the global naming tree is for the user to refer to the device user manual to determine the path to different managed objects in the device. 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.