Node A6 · Acronym decoder
IRS
Interface Requirements Specification
What it actually means
The specification stating what an interface is required to do — the data, timing, electrical, and physical requirements both sides must honor — as distinct from the design document recording how it's implemented. Interfaces are where independently built pieces meet, so their requirements deserve specification-grade rigor.
Where you'll meet it
Specification trees for software-intensive and multi-contractor systems.