Service flows for overriding barring services

1. Service flows for overriding barring services -- draft-rocky-sipping-override-barring-00.txt Rocky Wang <rocky.wang@huawei.com>

2. Background information • Barring Service • A subscriber can activate his barring service to avoid being disturbed. • overriding barring service • But for some reason under some circumstance, the incoming call should reach the callee even though his barring service is activated. This function is called “overriding barring service”. • To reflect the results of discussion at IETF 64, we are trying to find the solution of overriding barring services in use of SAML and also some other methods.

3. types of overriding • Type A：The special subscribers hold higher priorities and have the rights to override some others’ barring services. • E.g., the emergency center overrides common subscriber's DND. • Type B：The served subscriber can set a password which can be used to override his barring service. • Anybody who knows the password can override its barring service.

4. Approaches for type A (SAML) Calling Party Network Server Asserting Party Called Party Network Server Call Setup Request from caller Request Assertion User Authentication & Authorization SAML artifact INVITE + SAML artifact SAML request SAML response + assertion Check if caller can override callee’s barring Y Call setup to callee 4XX reject the call setup N

5. Approaches for type A (CPC) Calling Party Network Server Called Party Network Server Call Setup Request from caller INVITE + CPC Get CPC value, or get a mapping CPC value from OLI (ANSI ISUP) or ANI II Digits (MF signaling) Check if caller can override callee’s barring based on CPC Call setup to callee Y 4XX reject the call setup N

6. Approaches for type B • The called network server ask the caller for the password which can be used to override the callee’s barring service. • In-band password digits collect: The called network server can establish a session with the caller to play announcement and collect the password digits. • Out-band password digits collect: The called network server can try to collect the password by signaling method, e.g. KPML. • Challenge-based solution: The called network server can initiates a challenge procedure to ask the caller for the password. This is more useful if the caller endpoint can render some textual or picture information to guide the user to input the password.

7. Next step • Will collect the service flow for type A in use of the CPC parameter extension which is defined in draft-mahy-iptel-cpc. • Anything else?

8. Any Comments?

9. Thanks!