School of Specs

Every course

9 subjects. Each one is offered at up to three depths, from a quick start you finish in under an hour to the working reference.

How standards actually get made

The machinery behind 3GPP and the IETF: who writes a standard, how a proposal becomes a published document, and what a release really is.

How the work is done 21.900 v20.0.0 27 chapters 140 questions

The 5G system architecture

3GPP TS 23.501 — which functions a 5G network is made of, what each one is responsible for, and how they talk to each other.

One document 23.501 v20.2.0 38 chapters 214 questions

Ambient IoT — a tag with no battery

Devices with no battery, studied from Rel-18, specified in Rel-19 and extended in Rel-20 phase 2. Sixteen groups have filed documents against the work. What it is for, who did what, and where to read on.

An area of work 23.369 v20.0.0 25 chapters 125 questions

Sensing — the network as a radar

An area of 3GPP work that crosses the groups: using the network's own radio to detect and locate things. Studied in Rel-19, specified for Rel-20. What the work is for, who did what, and where to read on.

An area of work 25 chapters 126 questions

TSG RAN — the group that specifies the radio

3GPP's radio access group and its six working groups: who owns what, how a radio feature is agreed, and how to read what they produce.

A working group 38.300 v19.3.0 27 chapters 142 questions

CT1 — the group that writes what your phone says

3GPP's core-network protocol group: what it owns, how it decides, and how to read what it produces.

A working group 24.501 v20.0.0 25 chapters 124 questions

Inside one plenary: TSG SA#112, Singapore, June 2026

What a 3GPP plenary decides, how it decides it, and how to read the paper trail of any meeting yourself.

One meeting 23 chapters 112 questions

IMS — the call as an internet session

An area of 3GPP work that opened in Release 5 and is still being written for Release 20: the part of the network that sets a call up and carries it as an internet session instead of as a circuit. 345 work plan rows, 241 specifications, fourteen groups. What the work is for, who does what, and where to read on.

An area of work 25 chapters 118 questions

Satellites — a base station in orbit

An area of 3GPP work that crosses the radio groups and the system groups: reaching a phone or a sensor straight from orbit, with no mast in between. Nine releases of it, 155 named pieces of work, and a shelf of specifications that already exists. What the work is for, who did what, and where to read on.

An area of work 25 chapters 117 questions