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Requirements for. Marking of Calls initiated by Public Safety Answering Points (PSAPs). Henning Schulzrinne Stephen McCann Gabor Bajko Hannes Tschofenig. Problem space. PSAP wants to reach original emergency caller immediately (e.g., after disconnect)
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Requirements for Marking of Calls initiated by Public Safety Answering Points (PSAPs) Henning Schulzrinne Stephen McCann Gabor Bajko Hannes Tschofenig IETF - ECRIT
Problem space • PSAP wants to reach original emergency caller • immediately (e.g., after disconnect) • within some reasonable interval (minutes? days?) • Original caller: • same device (GRUU) • some device for same caller (Contact, From) • Want to bypass call treatments that may prevent call • call forwarding • call rejection (SPIT filtering, time-of-day rules, …) • other calls? • Non-goal: preferential treatment in the “network” IETF - ECRIT
Complications • Caller address may be unknown to original caller • call forwarding to first responders • ESNet multiple resolution steps • PSTN forwarding • Prevent abuse by non-emergency callers • will be abused by telemarketers IETF - ECRIT
Solution approaches • “This is a PSAP” • “This is an emergency-related call” • might apply to notification problem • “This is a return call for your call” • generalizes to non-emergency calls IETF - ECRIT
TBD • Sufficient starting point? • Limit duration of call back time window? • provide reasonable expectations • allow soft state for call-related state • does not matter with identity-based schemes IETF - ECRIT