Question: What are the two possible compliance scenarios for a SIP core in the Service Enabler Architecture Layer for Verticals (SEAL), regarding its architecture and reference points?
Option 1: Compliant with 3GPP specifications for signaling, but not for bearer plane functions; or fully compliant with another set of 3GPP specs for all aspects.
Option 2: Either fully compliant with one set of 3GPP specs for both signaling and bearer plane; or partially compliant with another set of 3GPP specs only for signaling reference points.
Option 3: Compliant with a custom architecture defined by the PLMN operator for the bearer plane; or compliant with a VAL service provider's proprietary SIP core architecture.
Option 4: Either compliant as a traditional 3GPP IP multimedia core network subsystem; or a non-3GPP SIP core complying with specific reference points for exposed interfaces.
Explanation: This answer highlights the flexibility in SIP core compliance within SEAL. The two correct scenarios are: (1) a SIP core fully compliant as a traditional 3GPP IP multimedia subsystem, or (2) a non-3GPP SIP core that complies with specific reference points for interoperability of exposed interfaces.