Diameter messages for IMS typically use which transport?

Interview
1

Q. Diameter messages for IMS typically use which transport?

a) TCP 80
b) UDP 1812
c) QUIC
d) port 3868

Check 🔎

:arrow_right: Correct answer: Letter d.

In the IMS architecture, Diameter is the protocol used for authentication, authorization, and accounting (AAA), as well as policy control over interfaces like Cx, Sh, Gx, and Rx.

Diameter messages typically use TCP or SCTP transport, but they are standardized to run over port 3868, which is the IANA-assigned port for Diameter applications.

This port is globally recognized in IMS networks to carry Diameter messages reliably.

Q. Diameter messages for IMS typically use which transport?

a) :x: TCP 80
→ Incorrect. TCP 80 is the default port for HTTP web traffic, not Diameter.

b) :x: UDP 1812
→ Incorrect. UDP 1812 is used by RADIUS, an older AAA protocol, not Diameter.

c) :x: QUIC
→ Incorrect. QUIC is a newer transport protocol used mainly for web acceleration over UDP, not related to IMS Diameter signaling.

d) :white_check_mark: port 3868
→ Correct. Diameter messages in IMS use port 3868, standardized for AAA and policy control in IMS networks.