+++ /dev/null
-.. _bgp-link-state:
-
-BGP Link-State
-==============
-
-Overview
---------
-
-BGP Link-State (BGP-LS) is an extension of the BGP protocol designed to
-redistribute information from an IGP database to a remote controller (most
-likely a Path Computation Element - PCE). BGP-LS does nothing more than
-transport IGP information. Therefore, it cannot be used to replace a Link State
-routing protocol like OSPF and IS-IS.
-
-Historically, the only way to get a network controller to collect an IGP
-database was to have it participate in the IGP itself as if it were a standard
-router. Since the controllers were usually located far from the IGP area,
-tunnels such as GRE were used to connect the controllers to the IGP area. This
-method was so impractical that an alternative solution was imagined: using the
-already deployed inter-domain BGP protocol to redistribute the various IGP
-databases.
-
-BGP Link-State as defined in `RFC7752
-<https://www.rfc-editor.org/rfc/rfc7752.html>`_ uses the AFI 16388 and SAFI 71.
-The BGP Link-State pseudo-prefixes distributed by the `NLRI (Network Layer
-Reachability Information)` uniquely define the following
-IGP information:
-
-- Nodes
-- Link
-- IPv4 Prefix
-- IPv6 Prefix
-
-They are called descriptors. In addition, a new type of BGP Attributes called
-"BGP-LS attributes" carries the other information related to a descriptor.
-
-NLRI and attribute information for BGP-LS is organized using the TLV format
-already used by IS-IS LSPs and OSPF opaque LSAs. The `list of TLV code points
-<https://www.iana.org/assignments/bgp-ls-parameters/bgp-ls-parameters.xhtml#node-descriptor-link-descriptor-prefix-descriptor-attribute-tlv>`_
-is maintained by IANA.
-
-Current implementation
-----------------------
-
-The current version can participate in BGP Link-State AFI / SAFI with
-third-party routers and forward the BGP Link-State descriptors and attributes to
-other routers. However, it can not generate BGP Link-State data from OSPF and
-IS-IS.
-
-IANA maintains a `registry of BGP-LS NRLI descriptor types
-<https://www.iana.org/assignments/bgp-ls-parameters/bgp-ls-parameters.xhtml#nlri-types>`_.
-Only the following RFC7752 NRLI types are supported by the current version:
-
-- Nodes
-- Link
-- IPv4 Prefix
-- IPv6 Prefix
-
-The BGP-LS attribute TLVs for these NLRI types are transmitted as is to other
-routers which means that all the current and future version are already
-supported.
-
-Show commands
--------------
-
-The following configuration enables the negotiation of the link-state AFI / SAFI
-with the 192.0.2.2 eBGP peer.
-
-.. code-block:: frr
-
- router bgp 65003
- neighbor 192.0.2.2 remote-as 65002
- neighbor 192.0.2.2 update-source 192.0.2.3
- !
- address-family link-state link-state
- neighbor 192.0.2.2 activate
- neighbor 192.0.2.2 route-map PERMIT-ALL in
- neighbor 192.0.2.2 route-map PERMIT-ALL out
- exit-address-family
- exit
- !
- route-map PERMIT-ALL permit 1
-
-The BGP-LS table can be displayed.
-
-.. code-block:: frr
-
- frr# show bgp link-state link-state
- BGP table version is 8, local router ID is 192.0.2.3, vrf id 0
- Default local pref 100, local AS 65003
- Network Next Hop Metric LocPrf Weight Path
- *> Node OSPFv2 ID:0x20 Local{AS:65001 ID:0 Area:0 Rtr:10.10.10.10:1.1.1.1}/48
- 0 65002 65001 i
- *> IPv4-Prefix OSPFv2 ID:0x20 Local{AS:65001 ID:0 Area:0 Rtr:10.10.10.10:1.1.1.1} Prefix{IPv4:89.10.11.0/24}/64
- 0 65002 65001 i
- *> IPv6-Prefix ISIS-L2 ID:0x20 Local{AS:65001 ID:0 Rtr:0000.0000.1003.00} Prefix{IPv6:12:12::12:12/128 MT:2}/74
- 0 65002 65001 i
- *> IPv6-Prefix OSPFv3 ID:0x20 Local{AS:65001 ID:0 Area:0 Rtr:10.10.10.10} Prefix{OSPF-Route-Type:1 IPv6:12:12::12:12/128 MT:2}/74
- 0 65002 65001 i
- *> Node OSPFv2 ID:0x20 Local{AS:65001 ID:0 Area:0 Rtr:10.10.10.10}/48
- 0 65002 65001 i
- *> Node ISIS-L1 ID:0x20 Local{AS:65001 ID:0 Rtr:0000.0000.1003.00}/48
- 0 65002 65001 i
- *> Link ISIS-L1 ID:0x20 Local{AS:65001 ID:0 Rtr:0000.0000.1001} Remote{AS:65001 ID:0 Rtr:0000.0000.1000} Link{IPv4:10.1.0.1 Neigh-IPv4:10.1.0.2 IPv6:2001::1 Neigh-IPv6:2001::2 MT:0,2}/132
- 0 65002 65001 i
-
-