masque B. Schwartz Internet-Draft Google LLC Intended status: Standards Track 4 October 2021 Expires: 7 April 2022 HTTP Datagram PING draft-schwartz-masque-h3-datagram-ping-01 Abstract This draft defines an HTTP Datagram Format Type for measuring the functionality of a Datagram path. Discussion Venues This note is to be removed before publishing as an RFC. Discussion of this document takes place on the mailing list (masque@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/masque/. Source for this draft and an issue tracker can be found at https://github.com/bemasc/h3-datagram-ping. 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 7 April 2022. Copyright Notice Copyright (c) 2021 IETF Trust and the persons identified as the document authors. All rights reserved. Schwartz Expires 7 April 2022 [Page 1] Internet-Draft HTTP Datagram PING October 2021 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. Conventions and Definitions . . . . . . . . . . . . . . . . . 2 2. PING Datagram Format Type . . . . . . . . . . . . . . . . . . 2 2.1. Format . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.2. Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Use cases . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. IANA considerations . . . . . . . . . . . . . . . . . . . . . 3 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 3 5.1. Normative References . . . . . . . . . . . . . . . . . . 3 5.2. Informative References . . . . . . . . . . . . . . . . . 4 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 4 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Conventions and Definitions 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 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 2. PING Datagram Format Type PING is an HTTP Datagram Format Type [I-D.draft-ietf-masque-h3-datagram]. It has no Additional Data. 2.1. Format PING Datagrams have the following format: PING { Sequence Number (i), Opaque Data (..), } Figure 1: PING Datagram Format All Sequence Number and Opaque Data values are potentially valid. Schwartz Expires 7 April 2022 [Page 2] Internet-Draft HTTP Datagram PING October 2021 2.2. Use The sender emits a PING Datagram with any even Sequence Number and any Opaque Data. Upon receiving a PING Datagram with an even Sequence Number, the recipient MUST reply with a PING Datagram whose Sequence Number is one larger, with empty Opaque Data. Intermediaries MUST forward PING Datagrams without modification, just like any other HTTP Datagram. 3. Use cases PING Datagrams can be used to characterize the end-to-end HTTP Datagram path associated with an HTTP request. For example, HTTP endpoints can easily use PING Datagrams to estimate the round-trip time and loss rate of the HTTP Datagram path. PING Datagrams are also suitable for use as DPLPMTUD Probe Packets [RFC8899]. This enables endpoints to estimate the HTTP Datagram MTU of each Datagram path, in order to avoid sending HTTP Datagrams that will be dropped. Note that these path characteristics can differ from those inferred from the underlying transport (e.g. QUIC), if the HTTP request traverses one or more HTTP intermediaries (see Section 3.7 of [I-D.draft-ietf-httpbis-semantics]). 4. IANA considerations IANA is directed to add the following entry to the "HTTP Datagram Format Types" registry: * Type: PING * Value: TBD * Reference: (This document) 5. References 5.1. Normative References [I-D.draft-ietf-masque-h3-datagram] Schinazi, D. and L. Pardue, "Using Datagrams with HTTP", Work in Progress, Internet-Draft, draft-ietf-masque-h3- datagram-03, 12 July 2021, . Schwartz Expires 7 April 2022 [Page 3] Internet-Draft HTTP Datagram PING October 2021 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 5.2. Informative References [I-D.draft-ietf-httpbis-semantics] Fielding, R. T., Nottingham, M., and J. Reschke, "HTTP Semantics", Work in Progress, Internet-Draft, draft-ietf- httpbis-semantics-19, 12 September 2021, . [RFC8899] Fairhurst, G., Jones, T., Tüxen, M., Rüngeler, I., and T. Völker, "Packetization Layer Path MTU Discovery for Datagram Transports", RFC 8899, DOI 10.17487/RFC8899, September 2020, . Acknowledgments Thanks to Alex Chernyakhovsky for constructive input. Author's Address Benjamin Schwartz Google LLC Email: bemasc@google.com Schwartz Expires 7 April 2022 [Page 4]