TM Space Data Link Protocol

Conformance Statement for `pkg/tmdl`, CCSDS 132.0-B-3

A2.1 GENERAL INFORMATION

A2.1.1 Identification of PICS

Field	Value
Date of Statement (DD/MM/YYYY)	24/08/2026
PICS Serial Number	ASTRO-TMDL-PICS-001
System Conformance Statement Cross-Reference	This document

A2.1.2 Identification of Implementation Under Test (IUT)

Field	Value
Implementation Name	astro/pkg/tmdl
Implementation Version	See `go.mod` / latest commit on `main`
Special Configuration	None
Other Information	Go library implementing CCSDS TM Space Data Link Protocol. Full pipeline: PhysicalChannel (MC mux/demux) -> MasterChannel (VC mux, MC_FSH/MC_OCF insertion, frame gap detection) -> VirtualChannel (single frame buffer) -> Services (VCP with native multi-packet packing via FHP and PacketSizer-based reassembly with loss resync, VCA with user-set status fields, VC_FSH and VC_OCF suppliers, VCF). Fixed frame length enforcement and conformant OID idle frames (mandatory PN fill, packet-carrying VCID). The sync layer (ASM, CCSDS pseudo-randomization, CADU wrapping/unwrapping) is handled by the separate `pkg/tmsc` package.

A2.1.3 Identification of Supplier

Field	Value
Supplier	Ravi Suhag
Contact Point for Queries	GitHub, github.com/ravisuhag/astro
Implementation Name(s) and Version(s)	astro/pkg/tmdl (Go package)
System Name(s)	Astro

A2.1.4 Identification of Specification

Field	Value
Specification	CCSDS 132.0-B-3 (TM Space Data Link Protocol, Blue Book, Issue 3, October 2021)
Have any exceptions been required?	Yes [ ] No [X]

NOTE. Every mandatory item is supported: the frame codec, all seven transfer services (VCP, VCA, VC_FSH, VC_OCF, VCF, MC_FSH, MC_OCF, MCF), and the protocol procedures at both ends. Optional items not supported: TM-9 (Packet Quality Indicator), TM-89 (SDLS Protocol).

A2.2 REQUIREMENTS LIST

Table A-1: TM Service Data Units

Item	Description	Reference	Status	Support
TM-1	Packet SDU	3.2.2	M	Yes
Space Packets are carried in `TMTransferFrame.DataField`. The `VirtualChannelPacketService` accepts packet data via `Send()`, pushes frames into a `VirtualChannel`, and delivers data via `Receive()`.
TM-2	VCA_SDU	3.2.3	M	Yes
`VirtualChannelAccessService` accepts fixed-length VCA SDUs via `Send()` with `VCASize` enforcement, pushes frames into a `VirtualChannel`, and delivers them via `Receive()`.
TM-3	FSH_SDU	3.2.4	M	Yes
`SecondaryHeader.DataField` carries the FSH SDU. Presence indicated by `PrimaryHeader.FSHFlag`. Encoded/decoded via `SecondaryHeader.Encode()` / `SecondaryHeader.Decode()`.
TM-4	OCF_SDU	3.2.5	M	Yes
`TMTransferFrame.OperationalControl`, 4-byte OCF field. Presence indicated by `PrimaryHeader.OCFFlag`. Extracted during decode when present.
TM-5	TM Transfer Frame	3.2.6	M	Yes
`TMTransferFrame` struct with `Encode()` / `DecodeTransferFrame()` round-trip support. Composed of Primary Header, optional Secondary Header, Data Field, optional OCF, and Frame Error Control.

Table A-2: Service Parameters

Item	Description	Reference	Status	Values Allowed	Support
	VCP Packet Service Parameters

TM-6	Packet	3.3.2.2	M	-	Yes
Packet data passed as `[]byte` to `VirtualChannelPacketService.Send()`. Frame pushed into `VirtualChannel`. Delivered via `Receive()`.
TM-7	GVCID	3.3.2.3	M	-	Yes
Derived from `PrimaryHeader.GVCID()` (TFVN + SCID + VCID). VCID configured at service construction.
TM-8	Packet Version Number	3.3.2.4	M	-	Yes
PVN validation was removed from the VCP service; it is delegated to the application layer. The first 3 bits of packet data carry the PVN per CCSDS.
TM-9	Packet Quality Indicator	3.3.2.5	O	-	No
Not implemented.
TM-10	Verification Status Code	3.3.2.6	C2	(see reference [10])	N/A
SDLS Option not implemented.
	VCA SDU Service Parameters

TM-11	VCA SDU	3.4.2.2	M	-	Yes
Fixed-length data passed to `VirtualChannelAccessService.Send()`. Size enforced against `vcaSize`. Frame pushed into `VirtualChannel`.
TM-12	VCA Status Fields	3.4.2.3	M	-	Yes
Both directions. Sending: `VirtualChannelAccessService.SetSendStatus(VCAStatus{...})` sets the Packet Order Flag, Segment Length ID, and First Header Pointer carried by subsequent `Send()` calls, the mandatory VCA Status Fields parameter of the VCA.request primitive (clause 3.4.3.2.2), whose semantics are the user's. Receiving: `LastStatus()` returns `VCAStatus{SyncFlag, PacketOrderFlag, SegmentLengthID, FirstHeaderPtr}` from the last received frame. The Synchronization Flag is not a user field: Clause 4.1.2.7.3.2 fixes it at '1' for a VCA_SDU and `Send()` always sets it.
TM-13	GVCID	3.4.2.4	M	-	Yes
Derived from `PrimaryHeader.GVCID()`. VCID configured at service construction.
TM-14	VCA SDU Loss Flag	3.4.2.5	O	-	Yes
`FrameGapDetector` tracks VC frame count gaps. `MasterChannel.VCFrameGap()` returns gap count after each `AddFrame()`.
TM-15	Verification Status Code	3.4.2.6	C2	(see reference [10])	N/A
SDLS Option not implemented.
	VC FSH SDU Service Parameters

TM-16	FSH SDU	3.5.2.2	M	-	Yes
`SecondaryHeader.DataField` carries the FSH_SDU on the wire. The VC_FSH service user installs it via `SetFSHSupplier()` on the VCP or VCA service, which fills the header of every frame that service emits (clause 3.5.1 makes the transfer synchronous with frame release), and reads it back with `LastFSH()`. Width is the channel's fixed `ChannelConfig.FSHDataLength` (clause 4.1.3.1.6).
TM-17	GVCID	3.5.2.3	M	-	Yes
Derived from `PrimaryHeader.GVCID()`.
TM-18	FSH_SDU Loss Flag	3.5.2.4	O	-	Yes
`MasterChannel.VCFrameGap()` reports the Virtual Channel Frame Count gap, which clause 3.5.2.4 names as the derivation for this flag; read it alongside the service's `LastFSH()`.
	OCF SDU Service Parameters

TM-19	OCF SDU	3.6.2.2	M	-	Yes
`TMTransferFrame.OperationalControl`, 4-byte field.
TM-20	GVCID	3.6.2.3	M	-	Yes
Derived from `PrimaryHeader.GVCID()`.
TM-21	OCF SDU Frame Loss Flag	3.6.2.4	O	-	Yes
`FrameGapDetector` integrated into `MasterChannel.AddFrame()`. Gap detected via MC/VC frame count tracking.
	VC Frame Service Parameters

TM-22	TM Frame	3.7.2.2	M	-	Yes
`VirtualChannelFrameService` accepts and delivers complete `*TMTransferFrame` objects via `Send()` / `Receive()`.
TM-23	GVCID	3.7.2.3	M	-	Yes
Derived from `PrimaryHeader.GVCID()`.
TM-24	Frame Loss Flag	3.7.2.4	O	-	Yes
`FrameGapDetector` integrated into `MasterChannel.AddFrame()`. Gap detected via MC/VC frame count tracking.
	MC FSH Service Parameters

TM-25	FSH SDU	3.8.2.2	M	-	Yes
`MasterChannel.SetFSHSupplier()` installs the MC_FSH service user: its FSH_SDU is placed into the Transfer Frame Secondary Header of every frame released through the master channel (clause 4.2.5.2), idle frames included. `MasterChannel.LastFSH()` delivers the SDU decommutated from the most recently received frame (clause 4.3.5.2). The SDU width is the channel's fixed `ChannelConfig.FSHDataLength` (clause 4.1.3.1.6); a mismatch is refused with `ErrFSHSizeMismatch` rather than silently truncated.
TM-26	MCID	3.8.2.3	M	-	Yes
`PrimaryHeader.MCID()` returns TFVN + SCID. It is the SAP address of the MC_FSH service: a `MasterChannel` is created for one SCID and rejects frames from another with `ErrSCIDMismatch`, so its FSH supplier and `LastFSH()` are scoped to that MCID.
TM-27	FSH_SDU Loss Flag	3.8.2.4	O	-	Yes
`MasterChannel.MCFrameGap()` reports the Master Channel Frame Count gap after each `AddFrame`, which clause 3.8.2.4 names as the way to derive the flag; read it alongside `LastFSH()`.
	MC OCF Service Parameters

TM-28	OCF SDU	3.9.2.2	M	-	Yes
`MasterChannel.SetOCFSupplier()` installs the MC_OCF service user: its 4-octet OCF_SDU is placed into the Operational Control Field of every frame released through the master channel (clause 4.2.5.3), idle frames included. `MasterChannel.LastOCF()` delivers the SDU from the most recently received frame (clause 4.3.5.2). Per-virtual-channel OCF remains available via the services' own `SetOCFSupplier` (VC_OCF, clause 3.6).
TM-29	MCID	3.9.2.3	M	-	Yes
`PrimaryHeader.MCID()`, scoped as the MC_OCF service's SAP address by the owning `MasterChannel` (see TM-26).
TM-30	OCF_SDU Loss Flag	3.9.2.4	O	-	Yes
`MasterChannel.MCFrameGap()` reports the Master Channel Frame Count gap after each `AddFrame` (clause 3.9.2.4); read it alongside `LastOCF()`.
	MC Frame Service Parameters

TM-31	TM Frame	3.10.2.2	M	-	Yes
Realized by `MasterChannel` rather than a `Service` type: `AddFrame()` routes inbound frames to Virtual Channels by VCID, `GetNextFrame()` pulls from the integrated multiplexer, SCID matching enforced.
TM-32	MCID	3.10.2.3	M	-	Yes
`PrimaryHeader.MCID()`. SCID validated in `MasterChannel.AddFrame()`.
TM-33	Frame Loss Flag	3.10.2.4	O	-	Yes
`MasterChannel.MCFrameGap()` and `VCFrameGap()` detect frame count gaps via `FrameGapDetector`.

C2: O if SDLS Option else N/A.

Table A-3: Service Primitives

Item	Description	Reference	Status	Support
	VCP Service Primitives

TM-34	VCP.request	3.3.3.2	M	Yes
`VirtualChannelPacketService.Send(data)` implements VCP.request. When `ChannelConfig` is set, packs packets into fixed-length frames using native FHP (multi-packet packing: tail-of-previous + start-of-next in same frame). `Flush()` fills the remaining space with an SPP idle packet and emits the resulting frame(s).
TM-35	VCP.indication	3.3.3.3	M	Yes
`VirtualChannelPacketService.Receive()` implements VCP.indication. When `ChannelConfig` is set, uses FHP to locate packet boundaries and `PacketSizer` (via `spp.PacketSizer`) to extract complete packets. `SetPacketSizer` must be called explicitly. Resyncs via FHP after VC frame count gaps. Skips idle frames and discards extracted idle packets (APID 0x7FF).
	VCA Service Primitives

TM-36	VCA.request	3.4.3.2	M	Yes
`VirtualChannelAccessService.Send(data)` implements VCA.request. Enforces fixed `vcaSize`, constructs a frame, stamps counters/CRC via `stampFrame()`, and pushes it into the `VirtualChannel`.
TM-37	VCA.indication	3.4.3.3	M	Yes
`VirtualChannelAccessService.Receive()` implements VCA.indication. Pulls the next frame from the `VirtualChannel` and returns its fixed-length Data Field.
	VC FSH Service Primitives

TM-38	VC_FSH.request	3.5.3.2	M	Yes
`SetFSHSupplier()` on the VCP or VCA service is the VC_FSH.request path: the supplier is polled as each frame is built and its FSH_SDU written into the secondary header, giving the synchronous transfer of clause 3.5.1. Direct per-frame construction stays available via `NewTransferFrame(..., secondaryHeaderData, ...)`, which sets the FSH flag automatically.
TM-39	VC_FSH.indication	3.5.3.3	M	Yes
`DecodeTransferFrame()` extracts the secondary header when the FSH flag is set; the VCP and VCA services deliver its SDU through `LastFSH()` as they decommutate each frame (clause 4.3.3.3), including on OID frames whose secondary header can still carry valid data (clause 4.1.4.6.3 note 1).
	VC OCF Service Primitives

TM-40	VC_OCF.request	3.6.3.2	M	Yes
OCF data passed via `NewTransferFrame(..., ocf)`. OCFFlag auto-set when OCF is present.
TM-41	VC_OCF.indication	3.6.3.3	M	Yes
`DecodeTransferFrame()` extracts 4-byte OCF when OCFFlag is set.
	VC Frame Service Primitives

TM-42	VCF.request	3.7.3.2	M	Yes
`VirtualChannelFrameService.Send(data)` decodes frame bytes and pushes the frame into the `VirtualChannel`.
TM-43	VCF.indication	3.7.3.3	M	Yes
`VirtualChannelFrameService.Receive()` pulls the next frame from the `VirtualChannel` and returns it as encoded bytes.
	MC FSH Service Primitives

TM-44	MC_FSH.request	3.8.3.2	M	Yes
`MasterChannel.SetFSHSupplier()` is the MC_FSH.request path: the supplier is polled at frame release and its FSH_SDU written into every frame of the master channel, which is the synchronous transfer clause 3.8.1 describes.
TM-45	MC_FSH.indication	3.8.3.3	M	Yes
`MasterChannel.AddFrame()` decommutates the secondary header per clause 4.3.5.2 and `MasterChannel.LastFSH()` delivers the FSH_SDU, with `MCFrameGap()` supplying the optional loss flag.
	MC OCF Service Primitives

TM-46	MC_OCF.request	3.9.3.2	M	Yes
`MasterChannel.SetOCFSupplier()` is the MC_OCF.request path: the supplier is polled at frame release and its OCF_SDU written into every frame of the master channel.
TM-47	MC_OCF.indication	3.9.3.3	M	Yes
`MasterChannel.AddFrame()` decommutates the Operational Control Field per clause 4.3.5.2 and `MasterChannel.LastOCF()` delivers the OCF_SDU, with `MCFrameGap()` supplying the optional loss flag.
	MC Frame Service Primitives

TM-48	MCF.request	3.10.3.2	M	Yes
Realized by `MasterChannel.AddFrame(frame)` rather than a `Service` type: accepts a `*TMTransferFrame` with SCID validation and routes it to the appropriate `VirtualChannel` by VCID.
TM-49	MCF.indication	3.10.3.3	M	Yes
Realized by `MasterChannel.GetNextFrame()`, which pulls the next frame from the integrated `VirtualChannelMultiplexer`.

Table A-4: TM Protocol Data Unit

Item	Description	Reference	Status	Support
TM-50	TM Transfer Frame	4.1.1	M	Yes
`TMTransferFrame` struct with `Encode()` / `DecodeTransferFrame()` round-trip.
TM-51	Transfer Frame Primary Header	4.1.2	M	Yes
`PrimaryHeader`, 6 octets (48 bits). All fields per CCSDS: Transfer Frame Version Number (2 bits, enforced as `00`), Spacecraft ID (10 bits), Virtual Channel ID (3 bits), OCF Flag (1 bit), MC Frame Count (8 bits), VC Frame Count (8 bits), Transfer Frame Data Field Status (16 bits). Big-endian encoding via `Encode()` / `Decode()`. Validated via `Validate()`.
TM-52	Transfer Frame Secondary Header	4.1.3	M	Yes
`SecondaryHeader` struct: Version Number (2 bits, enforced as `00`), Header Length (6 bits, 0-63), Data Field (variable). `Encode()` / `Decode()` / `Validate()` methods. Presence controlled by FSHFlag.
TM-53	Transfer Frame Data Field	4.1.4	M	Yes
`TMTransferFrame.DataField`, the payload, sized by `ChannelConfig.DataFieldCapacity()` as the fixed frame length minus the primary header, secondary header, and trailer (clause 4.1.4.2). OID frames (clause 4.1.4.6) carry the mandatory Pseudo Noise fill: `OIDSequence` implements the 32-cell LFSR of clause 4.1.4.6.2 with polynomial D0+D1+D2+D22+D32 and the 'all ones' seed, and each `MasterChannel` keeps one generator for its lifetime so the sequence is never restarted between frames (clause 4.1.4.6.2.1).
TM-54	Operational Control Field	4.1.5	M	Yes
`TMTransferFrame.OperationalControl`, 4 bytes (32 bits). Included when `OCFFlag` is set. Extracted during decode.
TM-55	Frame Error Control Field	4.1.6	M	Yes
`TMTransferFrame.FrameErrorControl`, 16-bit CRC-16-CCITT (polynomial 0x1021, init 0xFFFF). Auto-computed on encode via `crc.ComputeCRC16()`. Verified on decode; CRC mismatch returns error.

Table A-5: Protocol Procedures

Item	Description	Reference	Status	Support
TM-56	Packet Processing Function	4.2.2	M	Yes
`VirtualChannelPacketService.Send()` accepts packet data and packs it contiguously across fixed-length frames when `ChannelConfig` is set, with native FirstHeaderPtr management. `Flush()` fills spare data field space with SPP idle packets (APID 0x7FF), spanning into following frames when the spare space is under the 7-octet minimum packet size.
TM-57	VC Generation Function	4.2.3	M	Yes
`NewTransferFrame()` generates frames with SCID, VCID, data, optional secondary header, and optional OCF. CRC auto-computed. Frame counts applied by `stampFrame()` when a `FrameCounter` is provided.
TM-58	VC Multiplexing Function	4.2.4	M	Yes
`VirtualChannelMultiplexer` schedules frames from multiple Virtual Channels using weighted round-robin via `GetNextFrame()`. Integrated into `MasterChannel`. `GetNextFrameOrIdle()` creates the OID Transfer Frame clause 4.2.4.4 requires when no valid frame is available at release time: First Header Pointer '11111111110', a VCID that carries packets (clause 4.1.4.6.3, the lowest registered channel or the one pinned by `SetIdleVCID()`), a PN-filled data field, and MC/VC frame counts continuing the channel's sequence.
TM-59	MC Generation Function	4.2.5	M	Yes
`MasterChannel.GetNextFrame()` / `GetNextFrameOrIdle()` insert the MC_FSH and MC_OCF service data units into every frame released through the master channel (clause 4.2.5.2, clause 4.2.5.3) and refresh the frame error control field over the result, then hand the frame on. The Master Channel Frame Count is generated by the shared `FrameCounter`.
TM-60	MC Multiplexing Function	4.2.6	M	Yes
`PhysicalChannel` implements weighted round-robin MC multiplexing across registered `MasterChannel`s via `GetNextFrame()`. `GetNextFrameOrIdle()` creates the OID Transfer Frame of clause 4.2.6.4 when no master channel has a frame ready, choosing the lowest registered SCID so the result is deterministic.
TM-61	All Frames Generation Function	4.2.7	M	Yes
`PhysicalChannel.GetNextFrameOrIdle()` keeps the transmitted stream continuous, delegating idle frame creation to the chosen `MasterChannel` so the OID frame carries that channel's counts, PN fill, and MC_FSH/MC_OCF data. The frame error control field is appended here by `EncodeWithConfig()` when the channel carries one. CADU wrapping (ASM prepending, CCSDS pseudo-randomization) is done by the `tmsc` package.
TM-62	Packet Extraction Function	4.3.2	M	Yes
`VirtualChannelPacketService.Receive()` uses FHP to locate packet starts and `PacketSizer` to extract complete packets per clause 4.3.2. Resyncs after frame loss by aborting partial packets and finding next FHP. Skips idle frames and discards extracted idle packets (APID 0x7FF) per clause 4.3.2.
TM-63	VC Reception Function	4.3.3	M	Yes
`DecodeTransferFrame()` parses raw octets into a `TMTransferFrame`, verifying CRC and extracting all fields. `MasterChannel.AddFrame()` routes received frames to the appropriate `VirtualChannel` by VCID.
TM-64	VC Demultiplexing Function	4.3.4	M	Yes
`MasterChannel.AddFrame()` demultiplexes inbound frames to Virtual Channels by VCID. `TMServiceManager` dispatches to the correct VC service.
TM-65	MC Reception Function	4.3.5	M	Yes
`MasterChannel.GetNextFrame()` pulls the next frame from the integrated multiplexer.
TM-66	MC Demultiplexing Function	4.3.6	M	Yes
`PhysicalChannel.AddFrame()` demultiplexes inbound frames to the correct `MasterChannel` by SCID.
TM-67	All Frames Reception Function	4.3.7	M	Yes
`tmsc.UnwrapCADU()` handles ASM stripping and de-randomization. `tmdl.DecodeTransferFrame()` handles frame decoding.

Table A-6: Management Parameters

Item	Description	Reference	Status	Values Allowed	Support
	Managed Parameters for a Physical Channel

TM-68	Physical Channel Name	Table 5-1	M	Character String	Yes
`PhysicalChannel.Name`, configured at construction via `NewPhysicalChannel(name, config)`.
TM-69	Transfer Frame Length (octets)	Table 5-1	M	Integer	Yes
`ChannelConfig.FrameLength` defines the fixed frame length. Enforced by VCP (packing + idle-packet fill) and VCA (padding) during frame construction, and by the codec itself: `EncodeWithConfig()` and `DecodeTransferFrameWithConfig()` reject any other length with `ErrFrameLengthMismatch`. `DataFieldCapacity()` computes available data space.
TM-70	Transfer Frame Version Number (TFVN)	Table 5-1	M	'00' binary	Yes
`PrimaryHeader.VersionNumber`, enforced as `0` in `Validate()`.
TM-71	Valid Spacecraft IDs	Table 5-1	M	Integers	Yes
`PrimaryHeader.SpacecraftID`, 10 bits (0-1023). Validated in `Validate()`. Configurable per frame via `NewTransferFrame()`.
TM-72	MC Multiplexing Scheme	Table 5-1	M	Mission Specific	Yes
`PhysicalChannel` implements weighted round-robin MC multiplexing. Priority weights configured per `MasterChannel` via `AddMasterChannel()`.
TM-73	Presence of Frame Error Control	Table 5-1	M	Present ('1') / Absent ('0')	Yes
Configurable via `ChannelConfig.HasFEC`. The default entry points (`Encode()`, `DecodeTransferFrame()`) keep the field; `EncodeWithConfig()` / `DecodeTransferFrameWithConfig()` omit or verify it per the channel configuration, which is the Reed-Solomon case CCSDS permits.
	Managed Parameters for a Master Channel

TM-74	SCID	Table 5-2	M	Integer	Yes
`MasterChannel.scid`, configured at construction. Enforced in `AddFrame()`.
TM-75	Valid VCIDs	Table 5-2	M	Selectable set of integers (0-7)	Yes
`PrimaryHeader.VirtualChannelID`, 3 bits (0-7). `MasterChannel.channels` maps registered VCIDs.
TM-76	VC Multiplexing Scheme	Table 5-2	M	Mission Specific	Yes
`VirtualChannelMultiplexer` implements weighted round-robin scheduling. Priority weights determine how many consecutive frames each VC can transmit before yielding. Integrated into `MasterChannel`.
TM-77	Presence of MC_FSH	Table 5-2	M	Present ('1') / Absent ('0')	Yes
`PrimaryHeader.FSHFlag` indicates presence. Secondary header included/excluded at frame construction.
TM-78	MC_FSH Length (if present) (octets)	Table 5-2	M	Integer (2-64)	Yes
`SecondaryHeader.HeaderLength`, 6 bits (0-63). Data field length is variable.
TM-79	Presence of MC_OCF	Table 5-2	M	Present ('1') / Absent ('0')	Yes
`PrimaryHeader.OCFFlag` indicates presence. OCF included/excluded at frame construction.
	Managed Parameters for a Virtual Channel

TM-80	SCID	Table 5-3	M	Integer	Yes
`PrimaryHeader.SpacecraftID`. Set via `NewTransferFrame()`.
TM-81	VCID	Table 5-3	M	0 to 7	Yes
`PrimaryHeader.VirtualChannelID`. `VirtualChannel.VCID` configured at construction.
TM-82	Data Field Content	Table 5-3	M	Packets, VCA_SDU	Yes
`PrimaryHeader.SyncFlag` distinguishes: `0` = packets (VCP), `1` = VCA SDUs.
TM-83	Presence of VC_FSH	Table 5-3	M	Present ('1') / Absent ('0')	Yes
`ChannelConfig.FSHDataLength` > 0 makes the services emit a secondary header in every frame of the channel, which clause 4.1.2.7.2.3 requires to be static; `PrimaryHeader.FSHFlag` signals it on the wire.
TM-84	VC_FSH Length (if present) (octets)	Table 5-3	M	Integer	Yes
`ChannelConfig.FSHDataLength` is the managed value, fixed for the channel per clause 4.1.3.1.6 and subtracted from the data field capacity by `DataFieldCapacity()`; `SecondaryHeader.HeaderLength` carries it on the wire as total-length-minus-one (clause 4.1.3.2.3.2).
TM-85	Presence of VC_OCF	Table 5-3	M	Present ('1') / Absent ('0')	Yes
`PrimaryHeader.OCFFlag`.
	Managed Parameters for Packet Transfer

TM-86	Valid PVNs	Table 5-4	M	Set of Integers	Yes
PVN validation was removed from tmdl; the application layer is responsible for validating PVNs before passing packet data to the VCP service.
TM-87	Maximum Packet Length (octets)	Table 5-4	M	Integer	Yes
Maximum packet length bounded by `PacketSizer` (Space Packets: 65542 bytes max). Per-frame capacity derived from `ChannelConfig.DataFieldCapacity()`. Packets larger than one frame are automatically packed across multiple frames.
TM-88	Whether incomplete Packets are required to be delivered to the user at the receiving end	Table 5-4	M	Required, not required	Yes
Policy: not required. `VirtualChannelPacketService.Receive()` delivers only complete reassembled packets. A packet left incomplete by frame loss is silently discarded when the receiver resynchronizes from the next First Header Pointer; it is never delivered and no dedicated error is raised.

Table A-7: Protocol Specification with SDLS Option

Item	Description	Reference	Status	Support	Notes
TM-89	SDLS Protocol	(see ref. [10])	O	No	SDLS Option not implemented.
TM-90	Security Header	6.3.4	C3	N/A	SDLS Option not implemented.
TM-91	Transfer Frame Data Field in a TM Frame with SDLS	6.3.5	C3	N/A	SDLS Option not implemented.
TM-92	Security Trailer	6.3.6	C4	N/A	SDLS Option not implemented.
TM-93	Operational Control Field in a TM Frame with SDLS	6.3.7.2	C3	N/A	SDLS Option not implemented.
TM-94	Frame Error Control Field in a TM Frame with SDLS	6.3.8.2	C3	N/A	SDLS Option not implemented.
TM-95	Packet Processing Function with SDLS	6.4.2.2	C3	N/A	SDLS Option not implemented.
TM-96	Virtual Channel Generation Function with SDLS	6.4.3.2, 6.4.3.3	C3	N/A	SDLS Option not implemented.
TM-97	Virtual Channel Multiplexing Function with SDLS	6.4.4.2	C3	N/A	SDLS Option not implemented.
TM-98	Master Channel Multiplexing Function with SDLS	6.4.6.2	C3	N/A	SDLS Option not implemented.
TM-99	Error reporting	6.5.2.2	C4	N/A	SDLS Option not implemented.
TM-100	Packet Extraction Function with SDLS	6.5.3.2	C3	N/A	SDLS Option not implemented.
TM-101	Virtual Channel Reception Function with SDLS	6.5.4.2, 6.5.4.3	C3	N/A	SDLS Option not implemented.
TM-102	Virtual Channel Demultiplexing Function with SDLS	6.5.5.2	C3	N/A	SDLS Option not implemented.

C3: M if SDLS Option else N/A. C4: O if SDLS Option else N/A.

Table A-8: Additional Managed Parameters with SDLS Option

Item	Description	Reference	Status	Values Allowed	Support	Notes
TM-103	Presence of Space Data Link Security Header	Table 6-1	C5	Present ('1') / Absent ('0')	N/A	SDLS Option not implemented.
TM-104	Presence of Space Data Link Security Trailer	Table 6-1	C5	Present ('1') / Absent ('0')	N/A	SDLS Option not implemented.
TM-105	Length of Space Data Link Security Header (octets)	Table 6-1	C5	Integer (see ref. [10])	N/A	SDLS Option not implemented.
TM-106	Length of Space Data Link Security Trailer (octets)	Table 6-1	C5	Integer (see ref. [10])	N/A	SDLS Option not implemented.

C5: M if SDLS Option else N/A.

A2.3 CONFORMANCE SUMMARY

Overall Statistics

Category	Total Items	Supported	Not Supported
Mandatory (M)	78	78	0
Optional (O)	9	7	2
Conditional (C2)	2	0	0 (N/A)
Conditional (C3)	11	0	0 (N/A)
Conditional (C4)	2	0	0 (N/A)
Conditional (C5)	4	0	0 (N/A)
Total	106	85	2 + 19 N/A

Partially Supported Mandatory Items

None. Every mandatory item is fully supported.

The MC_FSH and MC_OCF services were the last gap. They are now master-channel level services: MasterChannel.SetFSHSupplier() and SetOCFSupplier() insert their service data units into every frame the master channel releases (the Master Channel Generation Function of clause 4.2.5), and LastFSH() / LastOCF() deliver what arrives (clause 4.3.5.2). The virtual-channel counterparts VC_FSH and VC_OCF have per-service suppliers of the same shape.

Non-Supported Optional Items

Item	Description	Reason
TM-9	Packet Quality Indicator	Not implemented. No packet quality/confidence reporting.
TM-89	SDLS Protocol	SDLS Option not implemented. Planned for future phase.

Supported Optional Items

Item	Description	Implementation
TM-14	VCA SDU Loss Flag	`FrameGapDetector` via `MasterChannel.VCFrameGap()`.
TM-18	FSH_SDU Loss Flag	`FrameGapDetector` via `MasterChannel.MCFrameGap()` / `VCFrameGap()`.
TM-21	OCF SDU Frame Loss Flag	`FrameGapDetector` via `MasterChannel.MCFrameGap()` / `VCFrameGap()`.
TM-24	Frame Loss Flag (VC Frame)	`FrameGapDetector` via `MasterChannel.VCFrameGap()`.
TM-27	FSH_SDU Loss Flag (MC)	`MasterChannel.MCFrameGap()`, read alongside `LastFSH()`.
TM-30	OCF_SDU Loss Flag (MC)	`MasterChannel.MCFrameGap()`, read alongside `LastOCF()`.
TM-33	Frame Loss Flag (MC Frame)	`FrameGapDetector` via `MasterChannel.MCFrameGap()` / `VCFrameGap()`.

Fully Supported Mandatory Items

All 78 mandatory items are fully supported. Key implementations:

Area	Items	Implementation
Service Data Units	TM-1-5
`TMTransferFrame` encode/decode, `SecondaryHeader`, `OperationalControl`.
VCP Service	TM-6-8, TM-34-35
`VirtualChannelPacketService` with native multi-packet packing via FHP, SPP idle-packet fill, `PacketSizer`-based reassembly with FHP resync on loss and idle-packet discard.
VCA Service	TM-11-13, TM-36-37
`VirtualChannelAccessService` with fixed SDU size enforcement, `LastStatus()` for status fields.
VCF Service	TM-22-23, TM-42-43
`VirtualChannelFrameService` with encode/decode via `VirtualChannel`.
VC FSH/OCF Services	TM-16-21, TM-38-41
Secondary header and OCF via `NewTransferFrame()` / `DecodeTransferFrame()`, per-channel OCF via `SetOCFSupplier`.
MC Frame Service	TM-31-33, TM-48-49
`MasterChannel` with SCID validation, `AddFrame()` / `GetNextFrame()`.
Protocol Data Unit	TM-50-55
`PrimaryHeader` (48-bit), `SecondaryHeader`, CRC-16-CCITT.
Packet Processing	TM-56, TM-62
VCP native multi-packet packing with FHP, SPP idle-packet fill on `Flush()`, `PacketSizer`-based extraction with FHP resync after loss and idle-packet discard.
VC Functions	TM-57-58, TM-63-64
`NewTransferFrame()`, `VirtualChannelMultiplexer` (weighted round-robin), `MasterChannel` demux by VCID.
MC Functions	TM-59-60, TM-65-66
`MasterChannel.AddFrame()` routes by VCID. `PhysicalChannel` MC mux/demux by SCID.
Physical Channel	TM-61, TM-67-69, TM-72
`PhysicalChannel` with MC mux/demux, `Name`, `ChannelConfig.FrameLength` (codec-enforced), MC multiplexing scheme, and conformant OID frames (PN-filled, packet-carrying VCID, counter-stamped, deterministic SCID). CADU wrapping (ASM + randomization) handled by `tmsc` package.
Management Params	TM-70-88
TFVN enforced, SCID/VCID validated, SyncFlag, FSHFlag, OCFFlag, configurable FECF presence, complete packet delivery.

Wire test vectors

The octets backing this statement live in the vector corpus — 29 vectors. Each vector names the clause it comes from and carries the derivation that produced it.

File
`tmdl/header.json`	21 vectors
`tmdl/interop.json`	8 vectors, captured from spacepackets 0.32.0

These are data files, so any implementation can check itself against the same octets. See CONTRACT.md for how, and how this is verified for what rests on a published vector versus a reading of the clause.