Provider Backbone Bridge Traffic Engineering
Encyclopedia
Provider Backbone Bridge Traffic Engineering (PBB-TE) is an approved telecommunications network
ing standard, IEEE 802.1Qay-2009. PBB-TE adapts Ethernet
technology to carrier class transport networks. It is based on the layered VLAN tags and MAC-in-MAC encapsulation defined in IEEE 802.1ah
(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. It was initially based on Nortel's Provider Backbone Transport (PBT).
PBB-TE's connection-oriented features and behaviors, as well as its OA&M approach, are inspired by SDH/SONET
. PBB-TE can also provide path protection levels similar to the UPSR (Unidirectional Path Switched Ring) protection in SDH/SONET networks.
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 VLAN ID (B-VID) and Destination MAC address
(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 broadasting 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 inherent in Ethernet, promising solutions that are 30% to 40% cheaper than T-MPLS
networks with identical features and capabilities, giving PBB-TE a better overall return on investment.
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
on June 18, 2009. It was published in August 2009.
Telecommunications network
A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in the network must have a unique address so messages or connections...
ing standard, IEEE 802.1Qay-2009. PBB-TE adapts Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
technology to carrier class transport networks. It is based on the layered VLAN tags and MAC-in-MAC encapsulation defined in IEEE 802.1ah
IEEE 802.1ah
Provider Backbone Bridges is a set of architecture and protocols for routing over a provider's network allowing interconnection of multiple Provider Bridge Networks without losing each customer's individually defined VLANs. It was initially created by Nortel before being submitted to the IEEE...
(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)
OA&M
Operations, administration and management or operations, administration and maintenance is a general term used to describe the processes, activities, tools, standards, etc involved with operating, administering, managing and maintaining any system...
is usually based on IEEE 802.1ag. It was initially based on Nortel's Provider Backbone Transport (PBT).
PBB-TE's connection-oriented features and behaviors, as well as its OA&M approach, are inspired by SDH/SONET
Sonet
Sonet may refer to:* Sonet Records, European record label* Synchronous optical networking * Saab Sonett...
. 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 IEEE 802.1ahIEEE 802.1ah
Provider Backbone Bridges is a set of architecture and protocols for routing over a provider's network allowing interconnection of multiple Provider Bridge Networks without losing each customer's individually defined VLANs. It was initially created by Nortel before being submitted to the IEEE...
Provider Backbone Bridges, adding a connection-oriented mode using point-to-point
Point-to-point
Point-to-point or point to point may refer to:Computing* Point-to-point construction, an electronics assembly technique* Point-to-point * Point-to-Point Protocol , part of the Internet protocol suite...
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 VLAN ID (B-VID) and Destination MAC address
MAC address
A Media Access Control address is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies, including Ethernet...
(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 broadasting 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 inherent in Ethernet, promising solutions that are 30% to 40% cheaper than T-MPLS
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 February 2006...
networks with identical features and capabilities, giving PBB-TE a better overall return on investment.
Key features of PBB-TE
- Traffic engineering and resiliency
- Secure, deterministic delivery
- 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 NortelNortel
Nortel Networks Corporation, formerly known as Northern Telecom Limited and sometimes known simply as Nortel, was a multinational telecommunications equipment manufacturer headquartered in Mississauga, Ontario, Canada...
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
IEEE Standards Association
The Institute of Electrical and Electronics Engineers Standards Association is an organization within IEEE that develops global standards in a broad range of industries, including: power and energy, biomedical and health care, information technology, telecommunication, transportation,...
on June 18, 2009. It was published in August 2009.
See also
- Connection-oriented EthernetConnection-oriented EthernetConnection-oriented Ethernet refers to the transformation of Ethernet, a connectionless communication system by design, into a connection-oriented system. The aim of connection-oriented Ethernet is to create a networking technology that combines the flexibility and cost-efficiency of Ethernet with...
- Carrier EthernetCarrier EthernetCarrier Ethernet is a marketing term for extensions to Ethernet to enable telecommunications network providers to provide Ethernet services to customers and to utilize Ethernet technology in their networks....
- Metro EthernetMetro EthernetA Metro Ethernet is a computer network that covers a metropolitan area and that is based on the Ethernet standard. It is commonly used as a metropolitan access network to connect subscribers and businesses to a larger service network or the Internet...
- Provider Backbone Bridges
- IEEE 802.1IEEE 802.1IEEE 802.1 is a working group of the IEEE 802 project of the IEEE Standards Association.It is concerned with:* 802 LAN/MAN architecture* internetworking among 802 LANs, MANs and other wide area networks* 802 Link Security* 802 overall network management...
- 802.1aq Shortest Path BridgingIEEE 802.1aq802.1aq Shortest Path Bridging or SPB in computer networking is a technology that greatly simplifies the creation and configuration of carrier, enterprise, and cloud networks which virtually eliminates human error, while enabling multipath routing...
- IEEE 802.1ah-2008 Provider Backbone Bridges
External links
- IEEE 802.1Qay project page -Retrieved 29 July 2011