Cabletron Systems EMM-E6 Ethernet MIBs, Review of Addressing, MAC Addresses, 00-00-1D-00-26-FB

CHAPTER 1: INTRODUCTION

1.9.1MIBs

The Management Information Bases (MIBs) are a database resident on the EMM-E6. Objects in the information base are uniquely identified by administratively assigned identifiers (called object identifiers or OIDs), and can be viewed, retrieved, or changed using an SNMP packet exchange over the network.

1.10REVIEW OF ADDRESSING

For network devices to recognize one another, unique identifiers, referred to as addresses, are required. The following sections are intended for review, and do not represent a comprehensive description of network addressing.

This section begins by discussing the two types of addressing used in TCP/IP networks, Internet Protocol (IP) addresses and Media Access Control (MAC) addresses. These descriptions are followed by an overview of the process of configuring addresses in a network, including examples of network Classes and the creation of subnets within networks.

1.10.1MAC Addresses

The MAC address is a unique, 48-bit binary number, associated with a specific physical connection to a network which is capable of generating packets. Examples of devices with MAC addresses include SNMP agents and DNI cards. MAC addresses are divided into 6 octets, and represented in hexadecimal form such as the following:

00-00-1D-00-26-FB

All MAC addresses are administered by the IEEE and are generally assigned at the time of manufacture, and cannot be changed. The first three octets uniquely identify the manufacturer. Cabletron devices’ MAC addresses all start with: 00-00-1D.

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