For the purpose of compatible interconnection of data processing equipment using the IEEE 802 MAC Service supported by interconnected IEEE 802 LANs (see 3.4) using different or identical Media Access Control methods, this standard specifies a general method for the operation of MAC Bridges. To this end it

• Positions the bridging function within an architectural description of the MAC Sublayer.
• Defines the principles of operation of the MAC Bridge in terms of the support and preservation of the MAC Service, and the maintenance of Quality of Service.
• Specifies the MAC Internal Sublayer Service provided by individual LANs to the Media Access Method Independent Functions that provide frame relay in the Bridge.
• Identifies the functions to be performed by Bridges, and provides an architectural model of the internal operation of a Bridge in terms of Processes and Entities that provide those functions.
• Establishes the requirements for a protocol between the Bridges in a Bridged LAN to configure the network, and specifies the distributed computation of a Spanning Tree active topology.
• Specifies the encoding of the Bridge Protocol Data Units (BPDUs).
• Establishes the requirements for Bridge Management in the Bridged LAN, identifying the managed objects and defining the management operations.
• Specifies how the management operations are made available to a remote manager using the protocol and architectural description provided by ISO/IEC 15802-2: 1995.
• Specifies performance requirements and recommends default values and applicable ranges for the operational parameters of a Bridge.
• Specifies the requirements to be satisfied by equipment claiming conformance to this standard.
• Specifies criteria for the use of MAC-specific bridging methods.

This standard specifies the operation of MAC Bridges that attach directly to IEEE 802 LANs, as specified in the relevant MAC standards for the MAC technology or technologies implemented.

The specification of Remote Bridges, which interconnect LANs using Wide Area Network (WAN) media for the transmission of frames between Bridges, is outside the scope of this standard.