10 The specifications, one at a time

10.1 Why a list like this is the useful part

Everything in the previous chapters is organised by who did the work. That is how the work happened, but it is not how anybody reads afterwards.

Afterwards you have a question — what does the architecture look like, what must the network guarantee, what goes on the wire — and you need the one document that answers it. This chapter is that index.

27 specifications are touched, out of 3599 active 3GPP specifications altogether ^{[2] [3]}. Eleven of them exist because of this work; the other sixteen existed already and are being changed.

10.2 The eleven this work created

Document	What it is	Documents	Version
TS 22.137 TS 22.137	the requirements: what the system must be able to do	119	19.1.0
TR 22.837 TR 22.837	the original use-case study	518	19.4.0
TR 23.700-14 TR 23.700-14	the architecture study	657	20.0.0
TS 23.137 TS 23.137	the architecture specification being written	262	0.3.0
TR 38.765 TR 38.765	the radio study report	168	20.0.0
TR 33.777 TR 33.777	the security and privacy study	226	0.6.0
TR 23.700-15 TR 23.700-15	the application-layer study	211	20.1.0
TS 23.138 TS 23.138	the application-layer specification being written	43	0.1.0
TR 28.893 TR 28.893	the charging study	67	1.0.0
TR 28.895 TR 28.895	the management study	61	0.3.0
TS 29.545 TS 29.545	the protocol of the new function, stage 3	1	0.1.0

Seven of those eleven are study reports. Four are specifications, and three of those four are drafts — only TS 22.137 is finished.

The finished one is also the shortest to describe. Its whole statement of scope is one sentence:

The version column is the fastest reading of this table. A number starting 19 or 20 is approved; anything starting 0 is still being argued over.

10.3 The sixteen it changes

These are documents that existed before sensing and will carry a piece of it. For each one, what it is for in general comes first, because that is what most readers need to know before they can judge whether the change matters to them.

10.3.1 The 5G system itself

• TS 23.501 TS 23.501 is the 5G system architecture: the reference model, every network function and what each is for. Sensing updates the reference model and the network functions in it. 13 change requests.

• TS 23.502 TS 23.502 is the procedures of that system, the step-by-step message flows. Sensing updates procedures and service definitions. 8 change requests.

• TS 22.261 TS 22.261 is the overall 5G service requirements. Sensing added a section pointing at the new requirements document. 4 change requests.

10.3.2 The radio

• TR 38.901 TR 38.901 is the radio channel model, the shared assumptions every radio simulation in 3GPP starts from. The Rel-19 study added sensing to it. 26 documents, 23 of them change requests.

• TS 38.300 TS 38.300 is the overall description of the 5G radio network. Listed as changed by the RAN work item. No change request yet.

• TS 38.401 TS 38.401 is the architecture of that radio network. Listed as changed by the RAN work item. No change request yet.

• TS 38.473 TS 38.473 is F1AP, the protocol between the two halves of a split base station. 5 documents name it.

10.3.3 The application layer

• TS 23.255 TS 23.255 supports drone systems. 22 change requests — more than any other existing specification here except the radio channel model, TR 38.901, which has 23 TR 38.901.

• TS 23.437 TS 23.437 covers spatial maps. 7 change requests.

• TS 23.286 TS 23.286 covers vehicles. 3 change requests.

• TS 23.434 TS 23.434 and TS 23.436 TS 23.436 are on the application work item's list of documents to change. Neither has a sensing change request yet.

10.3.4 The protocols

• TS 29.510 TS 29.510 is the directory every network function registers in, so that others can find it. Sensing adds the new function to it. 3 change requests.

• TS 29.522 TS 29.522 is the interface through which outside applications talk to the network. On the protocol work item's list.

• TS 29.571 TS 29.571 holds the shared data types every service-based interface uses. On the protocol work item's list.

10.3.5 The odd one out

• TR 22.870 TR 22.870 is the 6G use-case study, and it carries three documents tagged with a sensing work item TR 22.870. It is the only place in this record that links sensing to 6G, and three documents is all there is.

10.4 Which document answers which question

The list above is arranged by what happened to each document. Most readers arrive with a question instead, so here is the same 27 arranged that way.

Your question	The document
What must the system be able to do?	TS 22.137 TS 22.137
What did people want it for?	TR 22.837 TR 22.837
How is the system put together?	TR 23.700-14, then TS 23.137 TR 23.700-14 TS 23.137
What does this do to 5G itself?	TS 23.501 and TS 23.502 TS 23.501 TS 23.502
Can the radio actually do it?	TR 38.765 TR 38.765
On what assumptions was that judged?	TR 38.901 TR 38.901
What will change in the radio network?	TS 38.300, TS 38.401, TS 38.473 TS 38.300 TS 38.401 TS 38.473
Is it safe and private?	TR 33.777 TR 33.777
How does an application use a result?	TR 23.700-15, then TS 23.138 TR 23.700-15 TS 23.138
How is it billed and managed?	TR 28.893 and TR 28.895 TR 28.893 TR 28.895
What goes on the wire?	TS 29.545 TS 29.545

Two of those rows will disappoint. "What will change in the radio network" has no change requests behind it yet, and "what goes on the wire" is a document at 0.1.0 with a single document naming it.

10.5 What "touched" means, and what was left out

A specification got into that list of 27 if at least two sensing documents name it, or if a work item lists it as one it will change. That rule has two consequences a careful reader should know.

• Two specifications were left out because exactly one document names each and no work item does ^[4]. One document alone is as likely a filing mistake as a real link, and a register that guesses is worse than one that abstains.

• Six of the 27 have no sensing change request recorded here and are on the list because a work item named them: TS 38.300, TS 38.401, TS 23.434, TS 23.436, TS 29.522 and TS 29.571. Promised, not yet delivered.

The counts are floors as well, for the same reason they are everywhere in this course: only documents carrying one of the 14 work item acronyms were counted, and 440 documents whose titles say "integrated sensing" or "ISAC" carry none ^[5].

10.6 Where to read the real thing, in order

This school carries the text of none of these. A sensible reading order, for somebody who has to work with the subject:

• R1. TS 22.137 — short, and it defines the vocabulary TS 22.137.

• R2. TR 22.837 — the use cases, if you want to know what was hoped for TR 22.837.

• R3. TR 23.700-14 — the architecture study, and then TS 23.137 for what is being specified out of it TR 23.700-14 TS 23.137.

• R4. TR 38.901 and TR 38.765 — the channel model and the radio evaluation TR 38.901 TR 38.765.

• R5. TR 33.777 — security and privacy, still being written TR 33.777.

Next: what the shape of the paperwork says about how finished any of this is — What the shape of the paperwork says.