In the INVITE sent from MSS towards IMS for SRVCC, what is the value set in the Request-URI inside this INVITE?

Q. In the INVITE sent from MSS towards IMS for SRVCC, what is the value set in the Request-URI inside this INVITE?

a) IMSI
b) ATU-STI
c) STN-SR
d) MSISDN


Check 🔎

:arrow_right: Correct answer: Letter c.

In SRVCC (Single Radio Voice Call Continuity), the INVITE from MSS (Mobile Switching Center Server) to IMS contains the STN-SR (Session Transfer Number for SRVCC) in the Request-URI, which is used to route the session to the correct S-CSCF in IMS.

Q. In the INVITE sent from MSS towards IMS for SRVCC, what is the value set in the Request-URI inside this INVITE?

a) :x: “IMSI”
→ Incorrect. IMSI is not used in the Request-URI for SRVCC INVITE.

b) :x: “ATU-STI”
→ Incorrect. ATU-STI is used in SRVCC procedures but not in Request-URI.

c) :white_check_mark: “STN-SR”
→ Correct. The STN-SR is set in the Request-URI for routing.

d) :x: “MSISDN”
→ Incorrect. MSISDN is not used in the Request-URI for SRVCC INVITE.