Plain-language definition
The SIP method used to carry an instant message or SMS over IMS.
Technical definition
SIP MESSAGE carries the message body (including SMS-over-IMS encapsulation per 3GPP) from the UE via P-CSCF and S-CSCF to the IP-SM-GW or application server.
Why it matters
Firewalls and SMSCs that handle IMS traffic must process SIP MESSAGE alongside MAP and SMPP.
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.