Provider Backbone Bridge Traffic Engineering (PBB-TE) is an approved

telecommunications network A telecommunications network is a group of nodes interconnected by telecommunications links that are used to exchange messages between the nodes. The links may use a variety of technologies based on the methodologies of circuit switching, message ...

ing standard, IEEE 802.1Qay-2009. PBB-TE adapts

Ethernet Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...

technology to carrier class transport networks. It is based on the layered

VLAN A virtual local area network (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer (OSI layer 2).IEEE 802.1Q-2011, ''1.4 VLAN aims and benefits'' In this context, virtual, refers to a physi ...

tags and MAC-in-MAC encapsulation defined in

IEEE 802.1ah IEEE 802.1ah is an amendment to the IEEE 802.1Q networking standard which adds support for Provider Backbone Bridges. It includes an architecture and a set of protocols for routing over a provider's network, allowing interconnection of multiple p ...

(Provider Backbone Bridges (PBB)), but it differs from PBB in eliminating flooding, dynamically created forwarding tables, and spanning tree protocols. Compared to PBB and its predecessors, PBB-TE behaves more predictably and its behavior can be more easily controlled by the network operator, at the expense of requiring up-front connection configuration at each bridge along a forwarding path. PBB-TE Operations, Administration, and Management (OAM) is usually based on

IEEE 802.1ag IEEE 802.1ag (also CFM) (''IEEE Standard for Local and Metropolitan Area Networks Virtual Bridged Local Area Networks Amendment 5: Connectivity Fault Management'') is a standard defined by IEEE. It defines protocols and practices for OAM (Operatio ...

. It was initially based on Nortel's Provider Backbone Transport (PBT). PBB-TE's connection-oriented features and behaviors, as well as its OAM approach, are inspired by

SDH SDH may refer to: Science, medicine and technology * Serine dehydratase, an enzyme * L-sorbose 1-dehydrogenase, an enzyme * Succinate dehydrogenase, an enzyme * Shubnikov–de Haas effect * Social Determinants of Health, economic and social condi ...

SONET Synchronous optical networking (SONET) and synchronous digital hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams synchronously over optical fiber using lasers or highly coherent light from light-emitting diode ...

. PBB-TE can also provide path protection levels similar to the UPSR (Unidirectional Path Switched Ring) protection in SDH/SONET networks.

Principle of operation

The IEEE 802.1Qay PBB-TE standard extends the functionality of

Provider Backbone Bridges, adding a connection-oriented mode using point-to-point trunks that deliver resiliency and configurable performance levels. A service is identified by an I-SID (Backbone Service Instance Identifier) and each service is associated with a PBB-TE trunk. Each PBB-TE trunk is identified by a triplet of B-SA, B-DA and B-VID. The B-SA and B-DA identify the source and destination bridges, respectively, that are the endpoints of the trunk. The B-VID is a backbone VLAN identifier that is used to distinguish different trunks to the same destination. The management system configures the PBB-TE trunks on all the edge and core bridges by creating static forwarding database entries; the management system is responsible for ensuring that there are no forwarding loops. The backbone edge bridges map frames to and from an I-SID and perform the MAC header encapsulation and decapsulation functions. The core bridges act as transit nodes. The packets are forwarded based on outer

ID (B-VID) and Destination

MAC address A media access control address (MAC address) is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment. This use is common in most IEEE 802 networking techno ...

(B-DA). Forwarding is based on the static forwarding database (FDB) entries; dynamic MAC learning is not used. Any incoming broadcast or multicast frames are either dropped or encapsulated as unicast within the trunk. All Destination Lookup Failure packets are dropped rather than flooded. By eliminating any broadcasting or flooding, and by using only the loop-free forwarding paths configured by management, there is no longer any need to use a spanning tree protocol. Path protection is provided by configuring one work and one protect B-VID for each backbone service instance. In case of work path failure (as indicated by loss of 802.1ag continuity check messages, CCMs) the source bridge swaps the B-VID value to redirect the traffic onto the preconfigured protection path within 50 ms. PBB-TE equipment leverages

economies of scale In microeconomics, economies of scale are the cost advantages that enterprises obtain due to their scale of operation, and are typically measured by the amount of output produced per unit of time. A decrease in cost per unit of output enables ...

inherent in Ethernet, promising solutions that are 30% to 40% cheaper than

T-MPLS T-MPLS or Transport MPLS is a transport network layer technology that uses extensions to a subset of the existing MPLS standards and is designed specifically for application in transport networks. Work to define T-MPLS was started by the ITU-T in Fe ...

networks with identical features and capabilities, giving PBB-TE a better overall return on investment.

Key features

* Traffic and resiliency * Secure * Service scalability * Operational simplicity * Ethernet tunneling with full MPLS interoperability * Service and transport layer independence—the services inside the tunnel could be Ethernet, IP, MPLS pseudo-wires, or VPLS.

History

Provider Backbone Bridge Traffic Engineering was originally developed in 2006 as a

Nortel Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario, Canada. It was founded in Montreal, Quebec, ...

specific protocol named Provider Backbone Transport (PBT). The company championed the technology and brought it to the IEEE 802.1 committee where it was renamed to PBB-TE and a working group, P802.1Qay, was chartered on May 7, 2007. 802.1Qay was in sponsor ballot from January 2009 to April 2009. It was ratified by the

IEEE Standards Association The Institute of Electrical and Electronics Engineers Standards Association (IEEE SA) is an operating unit within IEEE that develops global standards in a broad range of industries, including: power and energy, artificial intelligence systems, i ...

on June 18, 2009. It was published in August 2009.

References

External links

IEEE 802.1Qay project page
-Retrieved 29 July 2011 {{IEEE standards IEEE 802.1Qay Network architecture Network protocols Nortel protocols Avaya Ethernet standards

Principle of operation

Key features

History

See also

References

External links