Plain-language definition
The bridge between IMS messaging and traditional SMS.
Technical definition
The IP-SM-GW registers with the S-CSCF (third-party registration), converts SIP MESSAGE to MAP or SMPP and back, applies number portability and reports Ro/Rf charging.
Why it matters
It guarantees that IMS subscribers and legacy subscribers can message each other transparently.
Last reviewed 2026-09-12 by the Guardivia QoS Engineering Team. Product facts on this page describe current capabilities; items marked “where supported”, “optional”, “integration” or “consultancy” are confirmed per deployment.