To meet this challenge, common connection-oriented Ethernet solutions have chosen to rid themselves of the complex parts of packet transport to achieve stability and control.
Key connection-oriented Ethernet technologies used to achieve this include mainly IEEE 802.1ah, Provider Backbone Transport and MPLS-TP, and formerly T-MPLS.
Key data-plane differences from PBB include the static configuration of forwarding tables within Ethernet switches, dropping of multicast packets and the prevention of "flooding" of frames to unknown destination addresses.
PBT has been presented to IEEE802 and a new project has been approved to standardize it under the name of Provider Backbone Bridge Traffic Engineering (PBB-TE) (IEEE 802.1Qay), a modification to PBB.
Provider Backbone Bridges (PBB) is an Ethernet data-plane technology invented in 2004 by Nortel Networks (now Avaya).
It is sometimes known as MAC-in-MAC because it involves encapsulating an Ethernet datagram inside another one with new source and destination addresses (termed B-SA and B-DA).
PBT focuses on point-to-point connectivity, and may be capable of extension to point-to-multipoint, a key technology for advanced data applications such as IPTV.
However, T-MPLS has been stripped of the characteristics which originally made it attractive to carriers—control-plane automation, signaling, and QoS—and therefore has yet to prove its benefits for the transport network.
It is further associated with its ability to offer a broad range of added-value services, such as IPTV, Voice, and VPN, whose requirements can widely vary and pose technical difficulties when sharing the same infrastructure.
This limits the value customers attach to EIR services and undercuts carriers' opportunities to offer differentiated access to its excess capacity.