Network Working Group Y. Zhu Internet-Draft H. Chen Intended status: Standards Track China Telecom Expires: December 27, 2018 M. Chen Z. Du Huawei June 25, 2018 ISIS Extensions for Flex Ethernet Link Advertisement draft-zhu-ccamp-flexe-link-advertisement-00 Abstract This document specifies the extensions to the IS-IS routing protocol to carry and flood Flex Ethernet (FlexE) link state information. The FlexE link state information is necessary for a node or a controller to compute a path that is required to over FlexE links. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on December 27, 2018. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. Zhu, et al. Expires December 27, 2018 [Page 1] Internet-Draft FlexE Link Advertisement June 2018 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. FlexE Link . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. FlexE Sub-link . . . . . . . . . . . . . . . . . . . . . . . 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 4.1. FlexE Interface Sub-TLV . . . . . . . . . . . . . . . . . 5 5. Security Consideration . . . . . . . . . . . . . . . . . . . 5 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction Flex Ethernet (FlexE) [I-D.izh-ccamp-flexe-fwk] provides a generic mechanism for supporting a variety of Ethernet MAC rates that may or may not correspond to any existing Ethernet PHY rate. This includes MAC rates that are both greater than (through bonding) and less than (through sub-rate and channelization) the Ethernet PHY rates used to carry Ethernet traffic. FlexE supports interface bonding, a bonded interface is consisted of from 1 to n 100GBASE-R Ethernet interfaces (other rates of interface will be supported in the future), the bonded interface is called FlexE interface in this document. FlexE also supports interface channelization, a FlexE interface can be channelized into multiple sub-interfaces, the sub-interface is called FlexE sub-interface in the rest of this document. The FlexE mechanism operates using a calendar which assigns 66B block positions on sub-calendars on each PHY of a FlexE interface to each of the FlexE flows. The calendar has a granularity of 5G, and has a length of 20 slots for a 100G interface. Currently, only 100GBASE-R PHY and 5G granularity are supported in FlexE implementation agreement version 1.0 [FlexE], other types (e.g., 200G, 400G) of PHY and granularities (e.g., 25G) will be supported in the future. Zhu, et al. Expires December 27, 2018 [Page 2] Internet-Draft FlexE Link Advertisement June 2018 A FlexE interface has a number of time slots resource. These time slots can be transparent to the upper layer application, the upper layer application (e.g., RSVP-TE) can just treat the FlexE interface as a normal Ethernet interface or the time slots can be allocated to form a FlexE sub-interface though configuration or some dynamic protocols. The later is called channelization. How to signal or configure the FlexE sub-interface is out of the scope of this document. The logical link that connects two FlexE interfaces residing in two adjacent nodes is called FlexE link, and the logical link that connects two FlexE sub-interfaces residing in two adjacent nodes is call FlexE sub-link. More details about FlexE can be found in FlexE framework document [I-D.izh-ccamp-flexe-fwk]. This document defines extensions to ISIS protocol to advertise the FlexE link and sub-link state information. 2. FlexE Link A FlexE link is a logical link that connects two FlexE interfaces, it looks like a LAG (Link Aggregation Group). This document defines a new sub-TLV, which is referred to as FlexE Interface sub-TLV, to the extended IS reachability TLV [RFC5307]. It is defined to describes the resources and attributes of a FlexE interface. The format of FlexE Interface sub-TLV is as below: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type = TBD1 | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | FlexE Group Number | Granularity | Reserved| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Available Slots | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: FlexE Interface sub-TLV The Type field is 2 octets in length and the value is TBD1. The Length field is 2 octets in length that indicates the total length of the TLV in octet. Zhu, et al. Expires December 27, 2018 [Page 3] Internet-Draft FlexE Link Advertisement June 2018 FlexE Group Number field is 20 bits in length and carries the FlexE Group [FlexE]number of the FlexE Group that the FlexE interface belongs. The Granularity is 1 octet in length and its value identifies the granularity of the FlexE time slots of a FlexE interface. Current OIF agreement only allows the "5G" granularity, other granularities may be defined in the future. Value Granularity ----- -------------- 0 Reserved 1 5G 2-254 Unassigned 255 Reserved For each PHY of a FlexE interface, there are two calendars, one is called Active calendar and the other is called Backup calendar. The two calendars are used to facilitate reconfiguration, for example, FlexE flow resizing can be achieved through calendar updates. More detail about FlexE calendar can be found [FlexE]. The Available Slots fields is 4-octet in length that indicates the maximum number of slots available on the active calendar of the FlexE interface. For each PHY of a FlexE interface, there are two calendars, one is called Active calendar and the other is called Backup calendar. The two calendars are used to facilitate reconfiguration, for example, FlexE flow resizing can be achieved through calendar updates. More detail about FlexE calendar can be found [FlexE]. For a FlexE interface, 5G granularity is only supported in [FlexE], more granularities may be supported in the future. To support this, FlexE Interface sub-TLV can occur multiple times in an extended IS reachability TLV, but for each granularity, only one FlexE Interface sub-TLV can be included and it carries the available time slots of the granularity of the FlexE interface. When multiple FlexE Interface sub-TLVs for the same granularity occur, only the first FlexE Interface sub-TLV is considered to be valid, the rests MUST be ignored. 3. FlexE Sub-link Through channelization, a FlexE interface can be sliced into a number of FlexE sub-interfaces, each FlexE sub-interface has dedicated bandwidth and is isolated from other FlexE sub-interfaces. A set of FlexE sub-interfaces can be allocated to a specific application/user Zhu, et al. Expires December 27, 2018 [Page 4] Internet-Draft FlexE Link Advertisement June 2018 to form a sliced network. Or a series of FlexE sub-interfaces can be concatenated (e.g., through Segment Routing) to form a leased line. A FlexE sub-link connects two FlexE sub-interfaces. From link characteristic point of view, a FlexE sub-link is same as an Ethernet link, it can be advertised and used as a normal link. 4. IANA Considerations 4.1. FlexE Interface Sub-TLV IANA is requested to allocate the following new sub-TLV types of top- level TLV 22 that have been reflected in the IS-IS sub-TLV registry for TLV 22: Value sub-TLV Name Reference ----- --------------- ------------- TBD1 FlexE Interface This document 5. Security Consideration This document describes a mechanism for advertising FlexE link state information through IS-IS LSPs and does not introduce any new security issues. 6. Acknowledgements 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5029] Vasseur, JP. and S. Previdi, "Definition of an IS-IS Link Attribute Sub-TLV", RFC 5029, DOI 10.17487/RFC5029, September 2007, . [RFC5307] Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008, . Zhu, et al. Expires December 27, 2018 [Page 5] Internet-Draft FlexE Link Advertisement June 2018 7.2. Informative References [FlexE] OIF, "Flex Ethernet Implementation Agreement Version 1.0 (OIF-FLEXE-01.0)", March 2016. [I-D.izh-ccamp-flexe-fwk] Hussain, I., Valiveti, R., Wang, Q., Andersson, L., Chen, M., and z. zhenghaomian@huawei.com, "GMPLS Routing and Signaling Framework for Flexible Ethernet (FlexE)", draft- izh-ccamp-flexe-fwk-05 (work in progress), March 2018. Authors' Addresses Yongqing Zhu China Telecom 109, West Zhongshan Road, Tianhe District, Guangzhou,China Email: zhuyq@gsta.com Huanan Chen China Telecom 109, West Zhongshan Road, Tianhe District, Guangzhou,China Email: chenhuanan@gsta.com Mach(Guoyi) Chen Huawei Email: mach.chen@huawei.com Zongpeng Du Huawei Email: duzongpeng@huawei.com Zhu, et al. Expires December 27, 2018 [Page 6]