BGP-LS
Advertisement of IGP Traffic Engineering Performance Metric
ExtensionsCisco Systems, Inc.USginsberg@cisco.comHuaweiITstefano@previdi.netHuawei101 Software Avenue, Yuhua DistrictNanjing, Jiangsu210012Chinabill.wu@huawei.comApstra, Inc.USjefftant.ietf@gmail.comCisco Systems, Inc.BrusselsBEcfilsfil@cisco.comNetworking Working GroupThis document defines new BGP-LS TLVs in order to carry the IGP
Traffic Engineering Extensions defined in IS-IS and OSPF protocols.The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP 14
when, and only when,
they appear in all capitals, as shown here.BGP-LS () defines NLRI and attributes in
order to carry link-state information. New BGP-LS Link-Attribute TLVs
are required in order to carry the Traffic Engineering Metric Extensions
defined in and .The following new Link Attribute TLVs are defined:This TLV advertises the average link delay between two directly
connected IGP link-state neighbors. The semantic of the TLV is
described in and .Type: 1114Length: 4.This sub-TLV advertises the minimum and maximum delay values
between two directly connected IGP link-state neighbors. The semantic
of the TLV is described in and .Type: 1115Length: 8.This sub-TLV advertises the average link delay variation between
two directly connected IGP link-state neighbors. The semantic of the
TLV is described in and .Type: 1116Length: 4.This sub-TLV advertises the loss (as a packet percentage) between
two directly connected IGP link-state neighbors. The semantic of the
TLV is described in and .Type:1117Length: 4.This sub-TLV advertises the residual bandwidth between two directly
connected IGP link-state neighbors. The semantic of the TLV is
described in and .Type: 1118Length: 4.This sub-TLV advertises the available bandwidth between two
directly connected IGP link-state neighbors. The semantic of the TLV
is described in and .Type: 1119Length: 4.This sub-TLV advertises the bandwidth utilization between two
directly connected IGP link-state neighbors. The semantic of the TLV
is described in and .Type: 1120Length: 4.Procedures and protocol extensions defined in this document do not
affect the BGP security model. See the 'Security Considerations' section
of for a discussion of BGP security. Also refer
to and for analysis of
security issues for BGP. Security considerations for acquiring and
distributing BGP-LS information are discussed in .The TLVs introduced in this document are used to propagate IGP
defined information ( and .) These TLVs represent the state and resources
availability of the IGP link. The IGP instances originating these TLVs
are assumed to have all the required security and authentication
mechanism (as described in and ) in order to prevent any security issue when
propagating the TLVs into BGP-LS. The advertisement of the link
attribute information defined in this document presents no additional
risk beyond that associated with the existing set of link attribute
information already supported in .This document requests assigning code-points from the registry
"BGP-LS Node Descriptor, Link Descriptor, Prefix Descriptor, and
Attribute TLVs" for the new Link Attribute TLVs defined in the table
below: The following people have substantially contributed to this document
and should be considered co-authors:The authors wish to acknowledge comments from Ketan Talaulikar.