57-515: SPB may refer to: [REDACTED] Look up SPB in Wiktionary, the free dictionary. Places [ edit ] Saint Petersburg , Russia Science and technology [ edit ] Shortest Path Bridging in the IEEE 802.1aq standard Slowly pulsating B star , a type of variable star Spindle pole body , the functional equivalent of
114-589: A mesh network . It is designed to preserve the plug-and-play nature that established Ethernet as the de facto protocol at layer 2. The technology provides VLANs on native Ethernet infrastructures using a link-state protocol to advertise both topology and VLAN membership. Packets are encapsulated at the edge either in MAC-in-MAC per IEEE 802.1ah or tagged per IEEE 802.1Q or IEEE 802.1ad and transported only to other members of VLAN. Unicast , multicast , and broadcast are supported and all routing
171-428: A BRAS. However, DSLAMs must not be allowed to communicate with each other, because carriers then lose the ability to control peer-to-peer connectivity. MEF E-TREE does just this, and further provides an efficient multicast fabric for the distribution of IPTV . SPBM offers both an ideal multicast replication model, where packets are replicated only at fork points in the shortest path tree that connects members, and also
228-649: A PBB header which indicates the source participating address in the SA while the DA indicates the locally significant group address this frame should be forwarded on and which source bridge originated the frame. The IEEE 802.1aq multicast forwarding tables are created based on computations such that every bridge which is on the shortest path between a pair of bridges which are members of the same service group will create proper forwarding database (FDB) state to forward or replicate frames it receives to that members of that service group. Since
285-460: A concrete example of such a system. As IEEE 802.1aq standardization progressed, some of the detailed mechanisms proposed by PLSB were replaced by functional equivalents, but all of the key concepts embodied in PLSB were carried forward into the standard. A primary feature of Shortest Path Bridging is the ability to use link state IS-IS to learn network topology. In SPBV the mechanism used to identify
342-517: A defunct bank in Iceland Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title SPB . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=SPB&oldid=1209128817 " Category : Disambiguation pages Hidden categories: Short description
399-453: A defunct bank in Iceland Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title SPB . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=SPB&oldid=1209128817 " Category : Disambiguation pages Hidden categories: Short description
456-464: A fallback spanning tree if there are configuration problems with SPBV. SPBV has been designed to manage a moderate number of bridges. SPBV differs from SPBM in that MAC addresses are learned on all bridges that lie on the shortest path and a shared VLAN learning is used since destination MACs may be associated with multiple SPVIDs. SPBV learns all MACs it forwards even outside the SPBV region. SPBM reuses
513-530: A large distributed bridge as viewed from outside the region. SPBV supports shortest path trees but SPBV also builds a spanning tree which is computed from the link state database and uses the Base VID. This means that SPBV can use this traditional spanning tree for computation of the Common and Internal Spanning Tree (CIST). The CIST is the default tree used to interwork with other legacy bridges. It also serves as
570-453: A link state control plane. A special attribute of SPBM is its ability to rebuild multicast trees in a similar time to unicast convergence, because it substitutes computation for signaling. When an SPBM bridge has performed the computations on a topology database, it knows whether it is on the shortest path between a root and one or more leaves of the SPT and can install state accordingly. Convergence
627-452: A mesh-connected Ethernet network utilizing multiple equal-cost paths. This permits SPB to support large Layer 2 topologies, with faster convergence, and improved use of the mesh topology when compared to networks configured with Spanning Tree Protocol. SPB augments IS-IS with a small number of TLVs and sub-TLVs, and supports two Ethernet encapsulating data paths, 802.1ad provider bridges (PB) and 802.1ah Provider Backbone Bridges (PBB). SPB
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#1732772938851684-456: A nonparticipating ring protocol and the IEEE 802.1aq network by activating a secondary attachment point and deactivating a primary attachment point. Failure recovery is as per normal IS-IS with the link failure being advertised and new computations being performed, resulting in new FDB tables. Since no Ethernet addresses are advertised or known by this protocol, there is no re-learning required by
741-415: A service needs configuration when a new attachment point comes or goes. The trees produced by the computations will automatically be extended or pruned as necessary to maintain connectivity. In some existing implementations this property is used to automatically (as opposed to through configuration) add or remove attachment points for dual-homed technologies such as rings to maintain optimum packet flow between
798-616: A shortest path Region which is the boundary of the shortest path topology and the rest of the VLAN topology (which may be any number of legacy bridges.) SPB operates by learning the SPB capable bridges and growing the Region to include the SPB capable bridges that have the same Base VID and MSTID configuration digest (Allocation of VIDs for SPB purposes). SPBV builds shortest path trees that support Loop Prevention and optionally support loop mitigation on
855-594: A single IS-IS protocol instance. SPB can use many VIDs, agreeing on which VIDs are used for which purposes. The IIH PDUs carry a digest of all the used VIDs, referred to as the Multiple Spanning Tree Configuration TLV which uses a common and compact encoding reused from 802.1Q . For the purposes of loop prevention SPB neighbors may also support a mechanism to verify that the contents of their topology databases are synchronized. Exchanging digests of SPB topology information, using
912-527: A transparent Ethernet LAN segment. It implements VLANs with scoped multicast trees, which means no egress discard of broadcast, unknown-unicast and multicast traffic , a feature common to approaches that use a small number of shared trees, hence the network does not simply degrade with size as the percentage of frames discarded goes up. The carrier-space equivalent of this application is the delivery of Ethernet VPN services to Enterprises over common carrier infrastructure. The required attributes are fundamentally
969-672: A type of variable star Spindle pole body , the functional equivalent of the mammalian centriole in yeast Superpressure balloon Transportation [ edit ] Scappoose Industrial Airpark , Oregon, USA, FAA LID Schynige Platte Bahn , a mountain railway in Switzerland Charlotte Amalie Harbor Seaplane Base , U.S. Virgin Islands, IATA airport code SPB Shepherd's Bush railway station , London, National Rail station code SPB Other uses [ edit ] Society of
1026-464: Is augmented by loop mitigation to provide fast data plane convergence. Group address and unknown destination individual frames are optimally transmitted to only members of the same Ethernet service. IEEE 802.1aq supports the creation of thousands of logical Ethernet services in the form of E-LINE, E-LAN or E-TREE constructs which are formed between non-participating logical ports of the IEEE 802.1aq network. These group address packets are encapsulated with
1083-706: Is designed to run in parallel with other network-layer protocols such as IPv4 and IPv6 . Standards mandate that the failure of two nodes to establish an SPB adjacency will not have a collateral impact, such as the rejection of an adjacency for other network-layer protocols (e.g. OSPF ). The IS-IS extensions defined in RFC 6329 that deliver standardized support for 802.1aq SPB are: 802.1aq has been designed to operate in parallel with other network layer protocols such as IPv4 and IPv6; therefore, failure of two nodes to establish an SPB adjacency will not cause network layer protocols to also reject an adjacency. RFC 6328 assigns 802.1aq
1140-443: Is different from Wikidata All article disambiguation pages All disambiguation pages SPB SPB may refer to: [REDACTED] Look up SPB in Wiktionary, the free dictionary. Places [ edit ] Saint Petersburg , Russia Science and technology [ edit ] Shortest Path Bridging in the IEEE 802.1aq standard Slowly pulsating B star ,
1197-415: Is different from Wikidata All article disambiguation pages All disambiguation pages IEEE 802.1aq IEEE 802.1aq is an amendment to the IEEE 802.1Q networking standard which adds support for Shortest Path Bridging ( SPB ). This technology is intended to simplify the creation and configuration of Ethernet networks while enabling multipath routing . SPB is designed to replace
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#17327729388511254-590: Is however implemented at the edges of the SPBM multicast tree to learn the B-MAC to MAC address relationship for correct individual frame encapsulation in the reverse direction (as packets arrive over the Interface). Properly implemented an IEEE 802.1aq network can support up to 1000 participating bridges and provide tens of thousands of layer 2 E-LAN services to Ethernet devices. This can be done by simply configuring
1311-417: Is intended where complete isolation of many separate instances of client LANs and their associated device MAC addresses is desired, and it therefore uses a full encapsulation (MAC-in-MAC a.k.a. IEEE 802.1ah ). The other (SPBV) is intended where such isolation of client device MAC addresses is not necessary, and it reuses only the existing VLAN tag on participating NNI links. Chronologically SPBV came first, with
1368-465: Is not gated by incremental discovery of a bridge's place on a multicast tree by the use of separate signaling transactions. However, SPBM on a node does not operate completely independently of its peers, and enforces agreement on the current network topology with its peers. This very efficient mechanism uses exchange of a single digest of link state covering the entire network view, and does not need agreement on each path to each root individually. The result
1425-417: Is not shown as it is trivial and simply uses the existing unicast FIBs to forward copies serially to the known other receivers. 802.1aq builds on all existing Ethernet operations, administration and management (OA&M). Since 802.1aq ensures that its unicast and multicast packets for a given virtual LAN (VLAN) follow the same forward and reverse path and use completely standard 802 encapsulations, all
1482-544: Is on symmetric shortest paths. The control plane is based on the Intermediate System to Intermediate System (IS-IS) routing protocol , leveraging a small number of extensions defined in RFC 6329 . On 4 March 2006 the working group posted 802.1aq draft 0.1. In March 2012 the IEEE approved the 802.1aq standard. In May 2013, the first public multivendor interoperability was demonstrated as SPB served as
1539-634: Is that B-MAC address are distributed or computed in the control plane, eliminating the B-MAC learning in PBB. Also SPBM ensures that the route followed is shortest path tree. The forward and reverse paths used for unicast and multicast traffic in an IEEE 802.1aq network are symmetric . This symmetry permits the normal Ethernet Continuity Fault Messages (CFM) IEEE 802.1ag to operate unchanged for SPBV and SPBM and has desirable properties with respect to time distribution protocols such as Precision Time Protocol ( PTP Version 2 ). Also existing Ethernet loop prevention
1596-401: Is that the volume of messaging exchanged to converge the network is in proportion to the incremental change in topology and not the number of multicast trees in the network. A simple link event that may change many trees is communicated by signaling the link event only; the consequent tree construction is performed by local computation at each node. The addition of a single service access point to
1653-743: Is used to associate opaque tie-breaking data with a node. The SPB Link Metric sub-TLV occurs within the Multi-Topology Intermediate System Neighbor TLV or within the Extended IS Reachability TLV. SPB Adjacency Opaque Equal Cost Tree Algorithm TLV also occurs within the Multi-Topology Intermediate System TLV or the Extended IS Reachability TLV. Where this sub-TLV is not present for an IS-IS adjacency, that adjacency will not carry SPB traffic for
1710-710: The Network Layer Protocol ID (NLPID) value 0xC1. This NLPID is used by SPB Bridges to indicate their ability to form adjacencies and operate as part of an 802.1aq domain. 802.1aq frames flow on adjacencies that advertise this NLPID in both directions, and nodes regard an adjacency that has not been advertised in both directions as non-existent (with infinite link metric). 802.1aq augments the normal IIH PDU with three new TLVs, which like all other SPB TLVs, travel within Multi-Topology TLV s, therefore allowing multiple logical instances of SPB within
1767-637: The PBB data plane which does not require that the Backbone Core Bridges (BCB) learn encapsulated client addresses. At the edge of the network the C-MAC (client) addresses are learned. SPBM is very similar to PLSB (Provider Link State Bridging) using the same data and control planes but the format and contents of the control messages in PLSB are not compatible. Individual MAC frames ( unicast traffic) from an Ethernet attached device that are received at
SPB - Misplaced Pages Continue
1824-719: The Precious Blood , Anglican religious order Socialist Party of Bangladesh , Political party in Bangladesh S. P. Balasubrahmanyam (1946–2020), Indian playback singer, actor, music director, voice actor and film producer SPB Software , mobile software developer Belarus Free Trade Union , a trade union in Belarus State Procurement Board in South Australia Sparisjóðabanki , also known as SPB hf.,
1881-423: The Precious Blood , Anglican religious order Socialist Party of Bangladesh , Political party in Bangladesh S. P. Balasubrahmanyam (1946–2020), Indian playback singer, actor, music director, voice actor and film producer SPB Software , mobile software developer Belarus Free Trade Union , a trade union in Belarus State Procurement Board in South Australia Sparisjóðabanki , also known as SPB hf.,
1938-474: The SPBM core and its learned encapsulations are unaffected by a transit node or link failure. Fast link failure detection may be performed using IEEE 802.1ag Continuity Check Messages (CCMs) which test link status and report a failure to the IS-IS protocol. This allows much faster failure detection than is possible using the IS-IS hello message loss mechanisms. Both SPBV and SPBM inherit the rapid convergence of
1995-407: The SPBM edge are encapsulated in a PBB (mac-in-mac) IEEE 802.1ah header and then traverse the IEEE 802.1aq network unchanged until they are stripped of the encapsulation as they egress back to the non-participating attached network at the far side of the participating network. Ethernet destination addresses (from UNI port attached devices) perform learning over the logical LAN and are forwarded to
2052-609: The SPVID. SPBV still allows learning of Ethernet MAC addresses but it can distribute multicast address that can be used to prune the shortest path trees according to the multicast membership either through Multiple MAC Registration Protocol (MMRP) or directly using IS-IS distribution of multicast membership. SPBV builds shortest path trees but also interworks with legacy bridges running Rapid Spanning Tree Protocol and Multiple Spanning Tree Protocol. SPBV uses techniques from MSTP Regions to interwork with non-SPT regions behaving logically as
2109-857: The amount of information that needs to be carried. The SPB Instance sub-TLV gives the Shortest Path Source ID (SPSourceID) for this node or topology instance. This is used in the formation of multicast destination addresses (DAs) for frames originating from this node or instance. There are multiple ECT algorithms defined for SPB and additional algorithms may be defined in the future including but not limited to ECMP - or hash-based behaviors and (*,G) Multicast trees. These algorithms will use this optional TLV to define new algorithm parametric data. For tie-breaking parameters, there are two broad classes of algorithms, one that uses nodal data to break ties and one that uses link data to break ties. The SPB Instance Opaque Equal cost Tree Algorithm TLV
2166-467: The appropriate participating B-MAC address to reach the far end Ethernet destination. In this manner Ethernet MAC addresses are never looked up in the core of an IEEE 802.1aq network. When comparing SPBM to PBB, the behavior is almost identical to a PBB IEEE 802.1ah network. PBB does not specify how B-MAC addresses are learned and PBB may use a spanning tree to control the B-VLAN. In SPBM the main difference
2223-435: The backbone destination address (B-DA)+ backbone VLAN identifier (B-VID) combination are looked up to find the egress set of next hops. The only difference compared with classical Ethernet is that reverse learning is disabled for participating bridge backbone media access control (B-MAC) addresses and is replaced with an ingress check and discard (when the frame arrives on an incoming interface from an unexpected source). Learning
2280-519: The backbone for Interop 2013 in Las Vegas. In 2013 and 2014 SPB was used to build the InteropNet backbone with only one-tenth the resources of prior years. During Interop 2014 SPB was used as the backbone protocol which can enable software-defined networking (SDN) functionalities. The 2014 Winter Olympics were the first "fabric-enabled" Games using SPB "IEEE 802.1aq" technology. During
2337-464: The case of SPBV, or PBBs per IEEE 802.1ah in the case of SPBM) with an IS-IS link state control protocol running between Shortest Path bridges ( Network-to-network interface (NNI) links). The link state protocol is used to discover and advertise the network topology and compute SPTs from all bridges in the SPT Region. In SPBM, the backbone MAC (B-MAC) addresses of the participating nodes and also
SPB - Misplaced Pages Continue
2394-556: The computations are done in a distributed fashion. Each node computes the Ethernet-compliant forwarding behavior independently based on a normally synchronized common view of the network and UNI ports. Ethernet filtering Database (or forwarding) tables are populated locally to independently and deterministically implement its portion of the network forwarding behavior. The two different flavors of data path give rise to two slightly different versions of this protocol. One (SPBM)
2451-508: The games this fabric network could handle up to 54 Tbit/s of traffic. The Intermediate System to Intermediate System (IS-IS) protocol, as defined in the IETF proposed standard RFC 6329 , is used as the control plane for SPB. SPB requires no state machine or other substantive changes to IS-IS, and simply requires a new Network Layer Protocol Identifier (NLPID) and set of TLVs . SPB allows for shortest-path forwarding in
2508-546: The given topology instance. The SPBM Service Identifier and Unicast Address TLV is used to introduce service group membership on the originating node or to advertise an additional B-MAC unicast address present on, or reachable by the node. The SPBV MAC Address TLV is the IS-IS sub-TLV used for advertisement of group MAC addresses in SPBV mode. Shortest Path Bridging-VID (SPBV) and Shortest Path Bridging-MAC (SPBM) are two operating modes of 802.1aq. Both inherit key benefits of link state routing : SPBM offers emulation of
2565-405: The group address computation produce shortest path trees, there is only ever one copy of a multicast packet on any given link. Since only bridges on a shortest path between participating logical ports create forwarding database (FDB) state the multicast makes the efficient use of network resources. The actual group address forwarding operation operates more or less identically to classical Ethernet,
2622-506: The head-end replication model. These selections can be different for different members of the same Individual Service ID (I-SID) allowing different trade-offs to be made for different members. Figure 5 below is a quick way to understand what SPBM is doing on the scale of the entire network. Figure 5 shows how a 7-member E-LAN is created from the edge membership information and the deterministic distributed calculation of per source, per service trees with transit replication. Head-end replication
2679-481: The less state-intensive head-end replication model where in essence serial unicast packets are sent to all other members along the same shortest path first tree. These two models are selected by specifying properties of the service at the edge which affect the transit node decisions on multicast state installation. This allows for a trade-off to be made between optimum transit replication points (with their larger state costs) vs. reduced core state (but much more traffic) of
2736-429: The mammalian centriole in yeast Superpressure balloon Transportation [ edit ] Scappoose Industrial Airpark , Oregon, USA, FAA LID Schynige Platte Bahn , a mountain railway in Switzerland Charlotte Amalie Harbor Seaplane Base , U.S. Virgin Islands, IATA airport code SPB Shepherd's Bush railway station , London, National Rail station code SPB Other uses [ edit ] Society of
2793-628: The methods of 802.1ag and Y.1731 operate unchanged on an 802.1aq network. 802.1aq is the IEEE-sanctioned link state Ethernet control plane for all IEEE VLANs covered in IEEE 802.1Q. The Shortest Path Bridging virtual local area network identifier (VLAN ID) or Shortest Path Bridging VID (SPBV) provides a capability that is backward compatible with spanning tree technologies. The SPBM provides additional values that use Provider Backbone Bridge (PBB) capabilities. SPB (the generic term for both) combines an Ethernet data path (either IEEE 802.1Q in
2850-405: The older spanning tree protocols : IEEE 802.1D STP, IEEE 802.1w RSTP, and IEEE 802.1s MSTP. These block any redundant paths that can result in a switching loop , whereas SPB allows all paths to be active with multiple equal-cost paths, provides much larger layer-2 topologies, supports faster convergence times, and improves the efficiency by allowing traffic to load share across all paths of
2907-531: The optional SPB-Digest sub-TLV , allows nodes to compare information and take specific action where a mismatch in topology is indicated. Finally, SPB needs to know which shortest path tree (SPT) sets are being used by which VIDs, and this is carried in the Base VLAN Identifiers TLV . All SPB nodal information extensions travel within a new Multi-Topology (MT) capability TLV . There can be one or many MT-Capability TLVs present, depending on
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#17327729388512964-515: The ports facing the Ethernet devices to indicate they are members of a given service. As new members come and go, the IS-IS protocol will advertise the I-SID membership changes and the computations will grow or shrink the trees in the participating node network as necessary to maintain the efficient multicast property for that service. IEEE 802.1aq has the property that only the point of attachment of
3021-443: The project originally being conceived to address scalability and convergence of MSTP . At the time the specification for PBB was progressing it became apparent that leveraging both the PBB data plane and a link state control plane would significantly extend Ethernet's capabilities and applications. Provider Link State Bridging (PLSB) was a straw man proposal brought to the IEEE 802.1aq Shortest Path Bridging Working Group, to provide
3078-642: The same; complete transparency for customer Ethernet services (both point-to-point and LAN), and complete isolation between one customer's traffic and that of all other customers. A further consequence of SPBM's transparency in both data plane and control plane is that it delivers the MEF 6.1 service set. It also provides the carrier with the toolkit to support geo-redundant broadband backhaul; in these applications, many DSLAMs or other access equipment must be backhauled to multiple Broadband Remote Access Server (BRAS) sites, with application-determined binding of sessions to
3135-469: The service membership information for interfaces to non-participating devices ( User–network interface (UNI) ports) is distributed. Topology data is then input to a calculation engine which computes symmetric shortest path trees based on minimum cost from each participating node to all other participating nodes. In SPBV these trees provide a shortest path tree where individual MAC address can be learned and group address membership can be distributed. In SPBM
3192-449: The shortest path trees are then used to populate forwarding tables for each participating node's individual B-MAC addresses and for group addresses; Group multicast trees are subtrees of the default shortest path tree formed by (source, group) pairing. Depending on the topology, several different equal-cost multi-path trees are possible and SPB supports multiple algorithms per IS-IS instance. In SPB as with other link-state-based protocols,
3249-432: The tree is to use a different Shortest Path VLAN ID (SPVID) for each source bridge. The IS-IS topology is used both to allocate unique SPVIDs and to enable shortest path forwarding for individual and group addresses. Originally targeted for small, low-configuration networks, SPB grew into a larger project encompassing the latest provider control plane for SPBV and harmonizing the concepts of Ethernet's data plane. SPB defines
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