MS-721 Practice Question 3370

Exam: MS-721
Domain: Configure and manage Teams Phone
Difficulty: hard
Which SIP status response code sent from an on-premises SBC indicates to Direct Routing that the gateway is unable to process the call and requests retry on another SBC?

Answer Options

A
SIP 503 (Service Unavailable) or SIP 504 (Server Time-out)
B
SIP 200 (OK)
C
SIP 180 (Ringing)
D
SIP 100 (Trying)

Correct Answer

A: SIP 503 (Service Unavailable) or SIP 504 (Server Time-out)

Explanation

SIP response code 503 (Service Unavailable) or 504 (Server Time-out) instructs Microsoft Direct Routing to failover the call to the next priority SBC in the route.