NVO3 Working Group G. Mirsky Internet-Draft ZTE Corp. Intended status: Standards Track N. Kumar Expires: September 19, 2018 D. Kumar Cisco Systems, Inc. M. Chen Y. Li Huawei Technologies D. Dolson Sandvine March 18, 2018 OAM Header for use in Overlay Networks draft-ooamdt-rtgwg-ooam-header-04 Abstract This document introduces Overlay Operations, Administration, and Maintenance (OOAM) Header to be used in overlay networks to create Overlay Associated Channel (OAC) to ensure that OOAM control packets are in-band with user traffic and de-multiplex OOAM protocols. 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 September 19, 2018. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. 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 Mirsky, et al. Expires September 19, 2018 [Page 1] Internet-Draft OAM Header for use in Overlay Networks March 2018 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 1.1. Conventions used in this document . . . . . . . . . . . . 2 1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3 1.1.2. Requirements Language . . . . . . . . . . . . . . . . 3 2. General Requirements to OAM Protocols in Overlay Networks . . 3 3. Associated Channel in Overlay Networks . . . . . . . . . . . 4 4. Overlay OAM Header . . . . . . . . . . . . . . . . . . . . . 4 4.1. Use of OOAM Header in Active OAM . . . . . . . . . . . . 6 4.2. Use of OOAM Header in Hybrid OAM . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5.1. OOAM Message Types . . . . . . . . . . . . . . . . . . . 7 5.2. OOAM Header Flags . . . . . . . . . . . . . . . . . . . . 8 6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 8 8. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 9 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 9.1. Normative References . . . . . . . . . . . . . . . . . . 9 9.2. Informative References . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction New protocols that support overlay networks like VxLAN-GPE [I-D.ietf-nvo3-vxlan-gpe], GUE [I-D.ietf-nvo3-gue], Geneve [I-D.ietf-nvo3-geneve], BIER [RFC8296], and NSH [RFC8300] support multi-protocol payload, e.g. Ethernet, IPv4/IPv6, and recognize Operations, Administration, and Maintenance (OAM) as one of distinct types. That ensures that Overlay OAM (OOAM)packets are sharing fate with Overlay data packet traversing the underlay. This document introduces generic requirements to OAM protocols used in overlay networks and defines OOAM Header to be used in overlay networks to de-multiplex OOAM protocols. 1.1. Conventions used in this document Mirsky, et al. Expires September 19, 2018 [Page 2] Internet-Draft OAM Header for use in Overlay Networks March 2018 1.1.1. Terminology Term "Overlay OAM" used in this document interchangeably with longer version "set of OAM protocols, methods and tools for Overlay networks". NTP Network Time Protocol OAC Overlay Associated Channel OAM Operations, Administration, and Maintenance OOAM Overlay OAM PTP Precision Time Protocol 1.1.2. Requirements Language 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 [RFC2119]. 2. General Requirements to OAM Protocols in Overlay Networks OAM protocols, whether it is part of fault management or performance monitoring, intended to provide reliable information that can be used to identify defect, localize it and apply corrective actions. One of the main challenges that network operators may encounter is interpretations of reports of the defect or service degradation and correlation to affected services. In order to improve reliability of the correlation process we set forth the following requirements: REQ#1: Overlay OAM packets SHOULD be fate sharing with data traffic, i.e. in-band with the monitored traffic, i.e. follow exactly the same overlay and transport path as data plane traffic, in forward direction, i.e. from ingress toward egress end point(s) of the OAM test. REQ#2: Encapsulation of OAM control message and data packets in underlay network MUST be indistinguishable from underlay network forwarding point of view. REQ#3: Presence of OAM control message in overlay packet MUST be unambiguously identifiable. Mirsky, et al. Expires September 19, 2018 [Page 3] Internet-Draft OAM Header for use in Overlay Networks March 2018 REQ#4: It MUST be possible to express entropy for underlay Equal Cost Multipath in overlay encapsulation in order to avoid using data packet content by underlay transient nodes. 3. Associated Channel in Overlay Networks Associated channel in the overlay network is the channel that, by using the same encapsulation as user traffic, follows the same path through the underlay network as user traffic. In other words, the associated channel is in-band with user traffic. Creating notion of the overlay associated channel (OAC) in the overlay network ensures that control packets of active OAM protocols carried in the OAC are in-band with user traffic. Additionally, OAC allows development of OAM tools that, from operational point of view, function in essentially the same manner in any type of overlay. 4. Overlay OAM Header OOAM Header immediately follows the header of the overlay and identifies OAC. The format of the OOAM Header is: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | V | Msg Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags | Reserved | Next Prot | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ OOAM control message ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Overlay OAM Header format The OAM Header consists of the following fields: o V - two bits long field indicates the current version of the Overlay OAM Header. The current value is 0; o Msg Type - 14 bits long field identifies OAM protocol, e.g. Echo Request/Reply, BFD, Performance Measurement; o Length - two octets long field that is length of the OOAM control packet in octets; o Flags -two octets long field carries bit flags that define optional capability and thus processing of the OOAM control packet; Mirsky, et al. Expires September 19, 2018 [Page 4] Internet-Draft OAM Header for use in Overlay Networks March 2018 o Reserved - one octet field that MUST be zeroed on transmit and ignored on receipt; o Next Prot - one octet long field that defines optional payload that is present after the OOAM Control Packet. The format of the Flags field is: 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |T| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: Flags field format where: o T - Timestap block flag. o Reserved - must be set to all zeroes on transmission and ignored on receipt. The OOAM header may be followed by the Timestamp control block Figure 3 and then by OOAM Control Packet identified by the Msg Type field. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QTF | RTF | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp 1 | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp 4 | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: Timestamp block format where: QTF - Querier timestamp format RTF - Responder timestamp format Mirsky, et al. Expires September 19, 2018 [Page 5] Internet-Draft OAM Header for use in Overlay Networks March 2018 Timestamp 1-4 - 64-bit timestamp values Network Time Protocol (NTP), described in [RFC5905], is widely used and has long history of deployment. But it is the IEEE 1588 Precision Time Protocol (PTP) [IEEE.1588.2008] that is being broadly used to achieve high-quality clock synchronization. Converging between NTP and PTP time formats is possible but is not trivial and does come with cost, particularly when it is required to be performed in real time without loss of accuracy. And recently protocols that supported only NTP time format, like One-Way Active Measurement Protocol [RFC4656] and Two-Way Active Measurement Protocol [RFC5357], have been enhanced to support the PTP time format as well [RFC8186]. This document proposes to select PTP time format as default time format for Overlay OAM performance measurement. Hence QTF, RTF fields MUST be set to 0 if querier or responder use PTP time format respectively. If the querier or responder use the NTP time format, then QTF and/or RTF MUST be set to 1. Use of other values MUST be considered as error and MAY be reported. 4.1. Use of OOAM Header in Active OAM Active OAM methods, whether used for fault management or performance monitoring, generate dedicated test packets [RFC7799]. Format of an OAM test packet in overlay network presented in Figure 4. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Underlay network encapsulation ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Overlay network encapsulation ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + OOAM Header +-+-+-+-+-+-+-+-+ | |NextProt = None| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ OOAM control message ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4: Overlay OAM Header in Active OAM Control Packet Because active OAM method uses only OAM protocol value of Next Prot field in the OOAM header is set to None indicating that there's no content from other protocol immediately after OOAM control message in the packet. Mirsky, et al. Expires September 19, 2018 [Page 6] Internet-Draft OAM Header for use in Overlay Networks March 2018 4.2. Use of OOAM Header in Hybrid OAM Hybrid OAM Type I methods, whether used for fault management or performance monitoring, modify user data packets [RFC7799]. Format of such modified packet in overlay network presented in Figure 5. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Underlay network encapsulation ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ Overlay network encapsulation ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + OOAM Header +-+-+-+-+-+-+-+-+ | |NextProt = Data| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ OOAM control message ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ~ User data ~ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 5: Overlay OAM Header in Hybrid OAM Control Packet In case when OOAM header used for Hybrid Type I OAM method value of the Next Prot field is set to the value associated with the protocol of the user data. 5. IANA Considerations IANA is requested to create new registry called "Overlay OAM". 5.1. OOAM Message Types IANA is requested to create new sub-registry called "Overlay OAM Protocol Types" in the "Overlay OAM" registry. All code points in the range 1 through 15615 in this registry shall be allocated according to the "IETF Review" procedure as specified in [RFC8126] . Remaining code points are allocated according to the Table 1: Mirsky, et al. Expires September 19, 2018 [Page 7] Internet-Draft OAM Header for use in Overlay Networks March 2018 +---------------+--------------+-------------------------+ | Value | Description | Reference | +---------------+--------------+-------------------------+ | 0 | Reserved | | | 1 - 15615 | Unassigned | IETF Review | | 15616 - 16127 | Unassigned | First Come First Served | | 16128 - 16143 | Experimental | This document | | 16144 - 16382 | Private Use | This document | | 16383 | Reserved | This document | +---------------+--------------+-------------------------+ Table 1: Overlay OAM Protocol type 5.2. OOAM Header Flags IANA is requested to create sub-registry "Overlay OAM Header Flags" in "Overlay OAM" registry. Two flags are defined in this document. New values are assigned via Standards Action [RFC8126]. +-----------+-----------------+---------------+ | Flags bit | Description | Reference | +-----------+-----------------+---------------+ | Bit 0 | Timestamp field | This document | | Bit 1-15 | Unassigned | | +-----------+-----------------+---------------+ Table 2: Overlay OAM Flags 6. Security Considerations TBD 7. Contributors Work on this documented started by Overlay OAM Design Team with contributions from: Carlos Pignataro Cisco Systems, Inc. cpignata@cisco.com Erik Nordmark Arista Networks nordmark@acm.org Mirsky, et al. Expires September 19, 2018 [Page 8] Internet-Draft OAM Header for use in Overlay Networks March 2018 Ignas Bagdonas ibagdona@gmail.com David Mozes Mellanox Technologies Ltd. davidm@mellanox.com 8. Acknowledgement TBD 9. References 9.1. Normative References [IEEE.1588.2008] "Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems", IEEE Standard 1588, July 2008. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch, "Network Time Protocol Version 4: Protocol and Algorithms Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010, . 9.2. Informative References [I-D.ietf-nvo3-geneve] Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic Network Virtualization Encapsulation", draft-ietf- nvo3-geneve-06 (work in progress), March 2018. [I-D.ietf-nvo3-gue] Herbert, T., Yong, L., and O. Zia, "Generic UDP Encapsulation", draft-ietf-nvo3-gue-05 (work in progress), October 2016. Mirsky, et al. Expires September 19, 2018 [Page 9] Internet-Draft OAM Header for use in Overlay Networks March 2018 [I-D.ietf-nvo3-vxlan-gpe] Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol Extension for VXLAN", draft-ietf-nvo3-vxlan-gpe-05 (work in progress), October 2017. [RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M. Zekauskas, "A One-way Active Measurement Protocol (OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006, . [RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", RFC 5357, DOI 10.17487/RFC5357, October 2008, . [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, May 2016, . [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 8126, DOI 10.17487/RFC8126, June 2017, . [RFC8186] Mirsky, G. and I. Meilik, "Support of the IEEE 1588 Timestamp Format in a Two-Way Active Measurement Protocol (TWAMP)", RFC 8186, DOI 10.17487/RFC8186, June 2017, . [RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation for Bit Index Explicit Replication (BIER) in MPLS and Non- MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January 2018, . [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., "Network Service Header (NSH)", RFC 8300, DOI 10.17487/RFC8300, January 2018, . Authors' Addresses Greg Mirsky ZTE Corp. Email: gregimirsky@gmail.com Mirsky, et al. Expires September 19, 2018 [Page 10] Internet-Draft OAM Header for use in Overlay Networks March 2018 Nagendra Kumar Cisco Systems, Inc. Email: naikumar@cisco.com Deepak Kumar Cisco Systems, Inc. Email: dekumar@cisco.com Mach Chen Huawei Technologies Email: mach.chen@huawei.com Yizhou Li Huawei Technologies Email: liyizhou@huawei.com David Dolson Sandvine Email: ddolson@sandvine.com Mirsky, et al. Expires September 19, 2018 [Page 11]