draft-ietf-idr-bgp-ls-segment-routing-rld-00.txt   draft-ietf-idr-bgp-ls-segment-routing-rld-01.txt 
IDR Working Group G. Van de Velde, Ed. IDR Working Group G. Van de Velde, Ed.
Internet-Draft W. Henderickx Internet-Draft W. Henderickx
Intended status: Standards Track M. Bocci Intended status: Standards Track M. Bocci
Expires: January 28, 2018 Nokia Expires: June 21, 2018 Nokia
K. Patel K. Patel
Arrcus Arrcus
July 27, 2017 December 18, 2017
Signalling ERLD using BGP-LS Signalling ERLD using BGP-LS
draft-ietf-idr-bgp-ls-segment-routing-rld-00 draft-ietf-idr-bgp-ls-segment-routing-rld-01
Abstract Abstract
This document defines the attributes to use for BGP-LS to expose a This document defines the attributes to use for BGP-LS to expose ERLD
node or link ERLD "Entropy capable Readable Label Depth" to a "Entropy capable Readable Label Depth" from a node or link to a
centralised controller (PCE/SDN). centralised controller (PCE/SDN).
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [1]. document are to be interpreted as described in RFC 2119 [1].
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 28, 2018. This Internet-Draft will expire on June 21, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
skipping to change at page 2, line 44 skipping to change at page 2, line 44
ability to read the signalled number of labels before any action is ability to read the signalled number of labels before any action is
done upon the packet and SHOULD support entropy awareness found done upon the packet and SHOULD support entropy awareness found
within the signalled ERLD depth. within the signalled ERLD depth.
ERLD awareness of each node and link will allow a network SDN ERLD awareness of each node and link will allow a network SDN
controller to influence the path used for each tunnel. The SDN controller to influence the path used for each tunnel. The SDN
controller may for example only create tunnels with a label stack controller may for example only create tunnels with a label stack
smaller or equal as the ERLD of each node and link on the path. This smaller or equal as the ERLD of each node and link on the path. This
will allow the network to behave accordingly (e.g. make use of will allow the network to behave accordingly (e.g. make use of
Entropy Labels to improve ECMP) upon the imposed Segment Routing Entropy Labels to improve ECMP) upon the imposed Segment Routing
labels on each packet. label stack on each packet.
This document describes how to use BGP-LS to expose the ERLD of a This document describes how to use BGP-LS to expose the ERLD of a
node. node.
2. Conventions used in this document 2. Conventions used in this document
2.1. Terminology 2.1. Terminology
BGP-LS: Distribution of Link-State and TE Information using Border BGP-LS: Distribution of Link-State and TE Information using Border
Gateway Protocol Gateway Protocol
skipping to change at page 3, line 33 skipping to change at page 3, line 33
3. Problem Statement 3. Problem Statement
In existing technology both ISIS [4] and OSPF [3] have proposed In existing technology both ISIS [4] and OSPF [3] have proposed
extensions to signal the RLD (Readable Label Depth) and ELC (Entropy extensions to signal the RLD (Readable Label Depth) and ELC (Entropy
Label Capability) of a node or link. However, if a network SDN Label Capability) of a node or link. However, if a network SDN
controller is connected to the network through a BGP-LS session and controller is connected to the network through a BGP-LS session and
not through ISIS or OSPF technology, then both RLD and ELC needs to not through ISIS or OSPF technology, then both RLD and ELC needs to
be signaled in BGP-LS accordingly. This document describes the be signaled in BGP-LS accordingly. This document describes the
extension BGP-LS requires to transport the combination of RLD and ELC extension BGP-LS requires to transport the combination of RLD and ELC
into ERLD node and link attributes. into according ERLD attributes for nodes and links.
A network SDN controller having awareness of the ERLD Entropy capable A network SDN controller having awareness of the ERLD Entropy capable
Readable Label Depth can for example use it as a constraint on path Readable Label Depth can for example use it as a constraint on path
computation so that it can make sure that high bandwidth LSPs are not computation so that it can make sure that high bandwidth LSPs are not
placed on LAG links with smaller member bandwidths if they know the placed on LAG (Link Aggregation Group) links with smaller member
Entropy Label cannot be processed by the node at the ingress to the bandwidths if they know the Entropy Label cannot be processed by the
link. node at the ingress to the link.
4. ERLD support by a node 4. ERLD support by a node
Node ERLD is encoded in a new Node Attribute TLV, as defined in Node ERLD is encoded in a new Node Attribute TLV, as defined in
RFC7752 [2]. RFC7752 [2].
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
skipping to change at page 5, line 39 skipping to change at page 5, line 39
9.1. Normative References 9.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate [1] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997, Requirement Levels", BCP 14, RFC 2119, March 1997,
<http://xml.resource.org/public/rfc/html/rfc2119.html>. <http://xml.resource.org/public/rfc/html/rfc2119.html>.
[2] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and [2] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752, Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016, DOI 10.17487/RFC7752, March 2016,
<http://www.rfc-editor.org/info/rfc7752>. <https://www.rfc-editor.org/info/rfc7752>.
9.2. Informative References 9.2. Informative References
[3] Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S. [3] Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S.
Litkowski, "draft-ietf-ospf-mpls-elc", October 2016. Litkowski, "draft-ietf-ospf-mpls-elc", October 2016.
[4] Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S. [4] Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S.
Litkowski, "draft-ietf-isis-mpls-elc", October 2016. Litkowski, "draft-ietf-isis-mpls-elc", October 2016.
Authors' Addresses Authors' Addresses
 End of changes. 11 change blocks. 
14 lines changed or deleted 14 lines changed or added

This html diff was produced by rfcdiff 1.46. The latest version is available from http://tools.ietf.org/tools/rfcdiff/