Network Working Group D. Schinazi Internet-Draft Google LLC Intended status: Experimental November 04, 2019 Expires: May 7, 2020 Using QUIC Datagrams with HTTP/3 draft-schinazi-quic-h3-datagram-02 Abstract The QUIC DATAGRAM extension provides application protocols running over QUIC with a mechanism to send unreliable data while leveraging the security and congestion-control properties of QUIC. However, QUIC DATAGRAM frames do not provide a means to demultiplex application contexts. This document defines how to use QUIC DATAGRAM frames when the application protocol running over QUIC is HTTP/3 by adding an identifier at the start of the frame payload. Discussion of this work is encouraged to happen on the QUIC IETF mailing list quic@ietf.org [1] or on the GitHub repository which contains the draft: https://github.com/DavidSchinazi/draft- h3-datagram [2]. 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 May 7, 2020. Copyright Notice Copyright (c) 2019 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 Schinazi Expires May 7, 2020 [Page 1] Internet-Draft HTTP/3 Datagrams November 2019 (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 1.1. Conventions and Definitions . . . . . . . . . . . . . . . 2 2. HTTP/3 DATAGRAM Frame Format . . . . . . . . . . . . . . . . 3 2.1. Flow Identifiers . . . . . . . . . . . . . . . . . . . . 3 3. Flow Identifier Allocation . . . . . . . . . . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 4 6.1. Normative References . . . . . . . . . . . . . . . . . . 4 6.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 5 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction The QUIC DATAGRAM extension [I-D.pauly-quic-datagram] provides application protocols running over QUIC [I-D.ietf-quic-transport] with a mechanism to send unreliable data while leveraging the security and congestion-control properties of QUIC. However, QUIC DATAGRAM frames do not provide a means to demultiplex application contexts. This document defines how to use QUIC DATAGRAM frames when the application protocol running over QUIC is HTTP/3 [I-D.ietf-quic-http] by adding an identifier at the start of the frame payload. This design mimics the use of Stream Types in HTTP/3, which provide a demultiplexing identifier at the start of each unidirectional stream. Discussion of this work is encouraged to happen on the QUIC IETF mailing list quic@ietf.org [3] or on the GitHub repository which contains the draft: https://github.com/DavidSchinazi/draft- h3-datagram [4]. 1.1. 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 Schinazi Expires May 7, 2020 [Page 2] Internet-Draft HTTP/3 Datagrams November 2019 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 2. HTTP/3 DATAGRAM Frame Format When used with HTTP/3, the Datagram Data field of QUIC DATAGRAM frames uses the following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flow Identifier (i) ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | HTTP/3 Datagram Payload (*) ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: HTTP/3 DATAGRAM Frame Format Flow Identifier: A variable-length integer indicating the Flow Identifier of the datagram (see Section 2.1). HTTP/3 Datagram Payload: The payload of the datagram, whose semantics are defined by individual applications. 2.1. Flow Identifiers Flow identifiers represent bidirectional flows of datagrams within a single QUIC connection. These are conceptually similar to UDP ports and allow basic demultiplexing of application data. The primary role of flow identifiers is to provide a standard mechanism for demultiplexing application data flows, which may be destined for different processing threads in the application, akin to UDP sockets. Beyond this, a sender SHOULD ensure that DATAGRAM frames within a single flow are transmitted in order relative to one another. If multiple DATAGRAM frames can be packed into a single QUIC packet, the sender SHOULD group them by flow identifier to promote fate-sharing within a specific flow and improve the ability to process batches of datagram messages efficiently on the receiver. 3. Flow Identifier Allocation Implementations of HTTP/3 that support the DATAGRAM extension will provide a flow identifier allocation service. That service will allow applications co-located with HTTP/3 to request a unique flow identifier that they can subsequently use for their own purposes. The HTTP/3 implementation will then parse the flow identifier of Schinazi Expires May 7, 2020 [Page 3] Internet-Draft HTTP/3 Datagrams November 2019 incoming DATAGRAM frames and use it to deliver the frame to the appropriate application. The flow identifier allocation services on both endpoints in a connection will need to coordinate to agree on the meaning of each flow identifier. This will require signalling, which is currently work in progress. This signalling mechanism will also need a way to flow control the amount of flow identifiers generated by a given endpoint. 4. Security Considerations This document currently does not have additional security considerations beyond those defined in [I-D.ietf-quic-transport] and [I-D.pauly-quic-datagram]. 5. IANA Considerations This document has no IANA actions. 6. References 6.1. Normative References [I-D.ietf-quic-http] Bishop, M., "Hypertext Transfer Protocol Version 3 (HTTP/3)", draft-ietf-quic-http-23 (work in progress), September 2019. [I-D.ietf-quic-transport] Iyengar, J. and M. Thomson, "QUIC: A UDP-Based Multiplexed and Secure Transport", draft-ietf-quic-transport-23 (work in progress), September 2019. [I-D.pauly-quic-datagram] Pauly, T., Kinnear, E., and D. Schinazi, "An Unreliable Datagram Extension to QUIC", draft-pauly-quic-datagram-04 (work in progress), October 2019. [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, . Schinazi Expires May 7, 2020 [Page 4] Internet-Draft HTTP/3 Datagrams November 2019 6.2. URIs [1] mailto:quic@ietf.org [2] https://github.com/DavidSchinazi/draft-h3-datagram [3] mailto:quic@ietf.org [4] https://github.com/DavidSchinazi/draft-h3-datagram Acknowledgments The DATAGRAM frame identifier was previously part of the DATAGRAM frame definition itself, the author would like to acknowledge the authors of that document and the members of the IETF QUIC working group for their suggestions. Author's Address David Schinazi Google LLC 1600 Amphitheatre Parkway Mountain View, California 94043 United States of America Email: dschinazi.ietf@gmail.com Schinazi Expires May 7, 2020 [Page 5]