Supported Platforms
Understanding How Interface Sets Work with E-LINE and E-LAN Services on MX Series Routers
Provider backbone bridging (PBB) extends Layer 2 Ethernet switching to provide enhanced scalability, quality of service (QoS) features, and carrier-class reliability in service provider networks. The Junos OS implementation of PBB supports the IEEE 802.1ah (PBB) standards including the provisioning of Ethernet private line (E-LINE) (point-to-point) and Ethernet transparent LAN (E-LAN) (point-to-multipoint) services.
![]() | Note: PBB is supported only on MX Series routers with Dense Port Concentrators (DPCs). PBB is not supported on MX Series routers with Modular Port Concentrators (MPCs). |
To support hierarchical CoS schedulers on Ethernet interfaces and to transport E-LINE and E-LAN traffic over the provider backbone bridged network (PBBN) core, you can configure an existing feature in Junos OS called an interface set. An interface set groups a number of logical interfaces into one interface set name.
Figure 1 shows the relationship of the forwarding classes in this example. The three types of forwarding classes are Voice-EF, VPN-PR-DATA, and INET-BEST-EFFORT. These forwarding classes are associated with E-LINE 1, E-LINE 2, E-LAN 1, and E-LAN 2. E-LINE 1 and E-LINE 2 are bundled into interface set vuni-set1. E-LAN 1 and E-LAN 2 are bundled into interface set vuni-set2. The interface set then transports packets through the physical interface. Interface sets provide the same function as a virtual UNI in the carrier Ethernet.
Figure 1: Relationship of Forwarding Classes, Services, Interface Sets, and Physical Interface

To configure an interface set, include the interface-set statement at the [edit interfaces] hierarchy level.