Export of QUIC Information in IP Flow Information Export (IPFIX)

QUIC Packets are carried in UDP datagrams and exchanged for communication of QUIC endpoints . A QUIC packet consists of a QUIC header and a QUIC payload. QUIC Header is divided into Long Header and Short Header. Long Headers are used for packets that are sent prior to the establishment of 1-RTT keys. The Long Header contains an 8-bit Public Flag, a 32-bit QUIC Version, a variable-length Destination Connection ID, a variable-length Source Connection ID and Type-Specific field which has different content based on the Packet type. The Packet types that use the long header contain Version Negotiation Packet, Initial Packet, 0-RTT Packet, Handshake Packet and Retry Packet. Once 1-RTT keys are available, a sender switches to sending packets using the Short Header. The Short Header includes an 8-bit Public Flag, a variable-length Destination Connection ID and a Packet Number. QUIC payload MAY contain a sequence of Frames which begin with a Frame Type. In the generic Frame Layout, the Frame Type is followed by additional type-dependent fields. Since Stream in QUIC is the one core component to provide a lightweight, ordered byte-stream abstraction to an application, the Stream ID of Frames related to Stream is an important information that indicates the stream in which the Frame is located or that the Frame affects. This document specifies several new IPFIX Information Elements (IEs) within the "IPFIX Information Elements" registry for purposes of getting QUIC information. These IEs are used to export the main parameters of QUIC Header, QUIC Frame and Stream.

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 when, and only when, they appear in all capitals, as shown here. This document makes use of the terms defined in and . The following terms are used as defined in : IPFIX IPFIX Information Elements The following terms are used as defined in : QUIC Endpoint Server QUIC packet Frame Connection ID Stream Application

This section specifies the new IPFIX QUIC IEs. 8-bit flag defined in the QUIC Header (Section 17.2 and 17.3 of ), as the first byte of QUIC Packet, which primarily indicates the Packet Type and the Length of followed fields. 32-bit QUIC Version that is in use and determines how the rest of the protocol packet fields are interpreted. The Destination Connection ID included in the Long Header or Short Header of QUIC Packet. The Destination Connection ID is chosen by the recipient of the packet and is used to provide consistent routing. The Source Connection ID included by the Long Header of QUIC Packet. The Source Connection ID is used to set the Destination Connection ID used by the peer. 32-bit Supported Version included by Version Negotiation packet with the Long Header. The Packet Number that appears in some packet types such as Initial packet, 0-RTT packet and Handshake packet. The underlying packet number increases with each packet sent in a given packet number space. The Packet Number is an integer in the range 0 to 262-1. When present in a Long or Short Header, packet numbers are reduced and encoded in 1 to 4 bytes. Frame Type that indicates the type of Frame contained in the Payload of QUIC Packet. The Frame Type value uses a variable-length integer encoding which means that integers are encoded on 1, 2, 4, or 8 bytes and can encode 6-, 14-, 30-, or 62-bit values, respectively. Some Frame Types are defined in section 12.4 of . The Stream ID included in the Frame related to Stream such as RESET_STREAM frame, STOP_SENDING frame, STREAM frame and MAX_STREAM_DATA frame. A stream ID is a 62-bit integer (0 to 262-1) that is unique for all streams on a connection. Stream IDs are encoded as variable-length integers, which means that integers are encoded on 1, 2, 4, or 8 bytes and can encode 6-, 14-, 30-, or 62-bit values, respectively. The two least significant bits from a stream ID identify the stream types defined in section 2.1 of .

The IPFIX IEs listed in the Section 3, forwardingStatus (89) and some existing counter information provide answers to the following questions (amongst others). How many packets are forwarded or dropped using QUIC in a network? If dropped, for which reasons? What is the type of QUIC packet? What is the QUIC version that is in use? What is the Destination or Source Connection ID of QUIC packet? Have all the QUIC packets been fully received? Which frames does the QUIC packet carry? Which stream is the QUIC packet located in? Which stream is affected by the QUIC packet?

There exists no extra security considerations regarding allocation of these new IPFIX IEs compared to .

This document requests IANA to add new IPFIX QUIC IEs to the "IPFIX Information Elements" registry available at . Table 1 lists the new IPFIX QUIC IEs:

Name:: quicHeaderFlag

ElementID:: TBD1

Description:: The 8-bit flag defined in the QUIC Header (Section 17.2 and 17.3 of ). The meanings of the flag are provided in the first byte of the QUIC Header Packet .

Abstract Data Type:: unsigned8

Data Type Semantics:: flags

Additional Information:: See RFC9000 for the QUIC Header specification.

Reference:: [this document]

Name:: quicVersion

ElementID:: TBD2

Description:: 32-bit unsigned integer defining the number of Version, which is in use and determines how the rest of the protocol packet fields are interpreted. Its values are provided in the "QUIC Versions" IANA registry.

Abstract Data Type:: unsigned32

Data Type Semantics:: default

Additional Information:: See the assignments in the "QUIC Versions" IANA registry at https://www.iana.org/assignments/quic/quic.xhtml#quic-versions. See also RFC9000 for the QUIC Versions specification.

Reference:: [this document]

Name:: quicDestinationConnectionID

ElementID:: TBD3

Description:: The Destination Connection ID as defined in Section 7.2 of as a series of octets in IPFIX.

Abstract Data Type:: octetArray

Data Type Semantics:: default

Additional Information:: See Section 7.2 of for more details about The Destination Connection ID.

Reference:: [this document]

Name:: quicSourceConnectionID

ElementID:: TBD4

Description:: The Source Connection ID as defined in Section 7.2 of as a series of octets in IPFIX.

Abstract Data Type:: octetArray

Data Type Semantics:: default

Additional Information:: See Section 7.2 of for more details about The Source Connection ID.

Reference:: [this document]

Name:: quicSupportedVersion

ElementID:: TBD5

Description:: 32-bit unsigned integer defining the number of Version, which indicates the supported QUIC version of server. Its values are provided in the "QUIC Versions" IANA registry.

Abstract Data Type:: unsigned32

Data Type Semantics:: default

Additional Information:: See the assignments in the "QUIC Versions" IANA registry at https://www.iana.org/assignments/quic/quic.xhtml#quic-versions. See also RFC9000 for the QUIC Versions specification.

Reference:: [this document]

Name:: quicPacketNumber

ElementID:: TBD6

Description:: 8~32-bit unsigned integer defining the packet number of QUIC Header, which is used in determining the cryptographic nonce for packet protection.

Abstract Data Type:: unsigned32

Data Type Semantics:: default

Additional Information:: See Section 12.3 of for more details about The Packet Number.

Reference:: [this document]

Name:: quicFrameType

ElementID:: TBD7

Description:: 62-bit unsigned integer defining the value of Frame Type, which indicates the type of QUIC Frame. Its values are provided in the "QUIC Frame Types" IANA registry.

Abstract Data Type:: unsigned64

Data Type Semantics:: default

Additional Information:: See the assignments in the "QUIC Frame Types" IANA registry at https://www.iana.org/assignments/quic/quic.xhtml#quic-frame-types. See also RFC9000 for the Frame Types specification of QUIC.

Reference:: [this document]

Name:: quicStreamID

ElementID:: TBD8

Description:: 62-bit unsigned integer defining the value of Stream ID, which identifies a Stream. The two least significant bits from a stream ID identify the stream types defined in section 2.1 of .

Abstract Data Type:: unsigned64

Data Type Semantics:: identifier

Additional Information:: See Section 2.1 of for more details about The Stream ID.

Reference:: [this document]