IEEE 802.1ah
The focus of the IEEE 802.1ah standard is to define a network architecture and bridge protocols for Carrier Ethernet( CE) that are compatible and interoperable with the protocols of Provider Bridged Networks.
The protocols should enable the interconnection of such networks, as well as the scaling of any number (`2^20`) of service VLANs. In addition, 802.1ah supports network management and the Simple Network Management Protocol( SNMP).
At the same time, 802.1ah forms the migration of the Provider Bridges( PB) specified in 802.1ad to Provider Backbone Bridges( PBB), with which the number of customer-specific backbone VLANs (B- VLAN) can be increased as desired.