SSCA Registration Process 5

Question 1

What is third-party registration in SIP?

Accepted Answer

One UA submitting a REGISTER request on behalf of another UA's AOR

Answer

Third-party registration occurs when a UA (e.g., a PBX) sends a REGISTER for a different user's AOR using the From header to identify the requestor.

Question 2

What is the primary role of a SIP registrar in the registration process?

Accepted Answer

To accept REGISTER requests and maintain AOR-to-Contact bindings in a location service

Answer

The registrar stores AOR-to-Contact bindings in a location service database, enabling proxy servers to route incoming calls to the correct device.

Question 3

What is the Path header used for during SIP registration?

Accepted Answer

To record intermediate proxy routes so that inbound requests traverse the same path

Answer

The Path header (RFC 3327) allows edge proxies to insert themselves into the routing path for subsequent inbound requests to the registered UA.

Question 4

Which RFC is the primary specification defining the SIP REGISTER method and registration process?

Accepted Answer

RFC 3261

Answer

RFC 3261 is the core SIP specification that defines the REGISTER method, registrar behavior, binding management, and authentication flow.

Question 5

What does 'soft state' mean in the context of SIP registration?

Accepted Answer

The registration binding expires automatically and must be periodically refreshed by the UA

Answer

Soft state means the binding has a finite lifetime (Expires) and disappears unless the UA actively refreshes it before expiry.

(SSCA) Sip School Certified Associate Practice Test