The IP Multimedia Subsystem (IMS) Profile for Voice and SMS, documented in this Permanent Reference Document (PRD), defines a profile that identifies a minimum mandatory set of features that a category M1 wireless device and network are required to implement in order to guarantee an interoperable, high quality IMS-based telephony service and IMS-based and Non-Access-Stratum (NAS) based Short Message Service (SMS) over LTE radio access.
