Question: In the context of IP Multimedia Subsystem (IMS), what aspect(s) of Messaging in the IM CN Subsystem are identified for further study alongside architectural concepts and procedures?
Option 1: Security, Charging, Addressing, Privacy, Content Handling, Limitations, Filtering, Media Types, and Message Lengths
Option 2: Only ISIM and IMC related requirements for non-3GPP accesses
Option 3: Solely Service Enablers for Messaging without reuse of IMS service enablers
Option 4: Exclusively Overall IMS Architecture excluding Messaging specifics
Explanation: This is the correct answer because, according to the provided context, alongside describing architectural concepts and procedures for IMS Messaging, further study is specifically mentioned to include a broad range of aspects such as security expectations, charging, addressing, privacy, content handling, limitations, filtering, media types, and message lengths. These are all crucial elements for comprehensively understanding and implementing messaging services within the IMS framework.