Module draft19 

MoQT wire codec for draft-19.

Key changes from draft-18:

• Request ID field removed from GOAWAY entirely; control-stream and request-stream GOAWAY now share one format
• New Range Filter parameters (length-prefixed): SUBGROUP_FILTER (0x25), OBJECTID_FILTER (0x26), PRIORITY_FILTER (0x27), OBJECT_PROPERTY_FILTER (0x28) and TRACK_PROPERTY_FILTER (0x29)
• New Setup Options MAX_FILTER_RANGES (0x06) and MAX_REQUEST_UPDATES (0x08) (even KVP types, varint values)
• GROUP_ORDER (0x22) moves from PUBLISH_OK to SUBSCRIBE_TRACKS
• PUBLISH_BLOCKED renamed to PUBLISH_SKIPPED (still type 0x0F, wire identical)
• SUBSCRIPTION_FILTER renamed to LOCATION_FILTER (still parameter 0x21)
• REQUEST_ERROR adds CONFLICTING_FILTERS (0x35) and INVALID_FILTER (0x36); DUPLICATE_SUBSCRIPTION (0x19) removed as multiple concurrent subscriptions per Track are now allowed
• Session error TOO_MANY_REQUEST_UPDATES (0x1B) added
• Data stream headers (subgroup, datagram, fetch) are byte-for-byte identical to draft-18
• Object Status gets its own IANA registry (Section 15.9, Table 16) with a Payload column, and Section 11.2.1.1 defers to it: an Object has an empty payload “unless its Object Status value is registered as permitting a payload”. Draft-18 stated one blanket rule for every status instead — any non-zero status means an empty payload — so the answer used to be arithmetic on the code point and is now registry data, which every future registration must supply. The three assigned code points are unchanged (0x0 Normal, 0x3 End of Group, 0x4 End of Track) and the two rules happen to agree on all three. Modelled as types::PayloadPermission
• The control-message framing field after Message Length is renamed from Message Payload to Message Body (Section 10, Figure 3). Editorial: the bytes are unchanged
• OBJECT_DELIVERY_TIMEOUT (Property Type 0x02) and SUBGROUP_DELIVERY_TIMEOUT (0x06) become Track and Object Properties (Section 15.8, Table 14; they were Track-only in draft-18). Section 8 gives the new scope its meaning: set as an Object Property on the first object in a subgroup either value overrides the Track-level value for that subgroup, and on any other object in the subgroup it is ignored. This codec carries Object Properties as an opaque blob, so the change is recorded here rather than modelled
• The 1-byte Property Type range reserved for application-specific use moves from 0x38-0x3F to 0x78-0x7F (Section 2.5). The 2-byte range 0x3800-0x3FFF is unchanged. Draft-18 had assigned PRIOR_GROUP_ID_GAP (0x3C) and PRIOR_OBJECT_ID_GAP (0x3E) inside its own reserved range; draft-19 resolves that by moving the range and leaving the two assignments where they are

Modules

data_stream

Draft-19 data stream header encoding and decoding.

error_codes

Error, status and stream-reset code registries defined by draft-ietf-moq-transport-19.

fields

This draft’s field names for a decoded control message.

message

Draft-19 control message encoding and decoding.

types

Draft-19 object status values.