1. draft-ietf-ecrit-location-hiding-req Location Hiding: Problem Statement and Requirements Henning Schulzrinne, Laura Liess, Hannes Tschofenig, Barbara Stark, A. Kuett 7/29/081ECRIT - IETF 72 (Dublin)

2. Overview Makes no recommendation right now – probably needs overall service requirement. Assumes exiting ECRIT architecture – e.g., LoST may be operated by VSP – not, say, ISP-based HELD, LoST and call routing LbyR with PSAP access control out of scope – may not suffice for LoST 7/29/08ECRIT - IETF 72 (Dublin)2

3. High-level Requirements A: ISP SHOULD be able to withhold LI. B: End point and VSP MUST be able to route calls. C: VSP MUST be able to validate URL as emergency URL. D: PSAP MUST be able to get precise location information. 7/29/08ECRIT - IETF 72 (Dublin)3

4. Detailed requirements 1: no business relationship ISP & VSP 2: VSP outside PSAP jurisdiction 3: no manual configuration 4: same end point steps (SHOULD) 5: works for non-SIP 6: must work with PSAP holes 7: must not assume higher-level ESRPs 7/29/08ECRIT - IETF 72 (Dublin)4

5. Detailed requirements 8: different service boundaries for different services 9: no trial-and-error (otherwise trial-and- judgment ) 10: must work prior to call 11: discover dial string prior to call 12: minimal UA impact 13: must allow LoST usage for non-emergency services 15: calls may reach PSTN gateway 7/29/08ECRIT - IETF 72 (Dublin)5

6. Desirable No cost shifting to non-hiding ISPs, UAs, VSPs Minimal impact on LoST, SIP conveyance, DHCP Don’t rely on DHCP to configure LoST server 7/29/08ECRIT - IETF 72 (Dublin)6

7. To do Req: no impact on automated call testing – SHOULD allow PSAP to provide location information for validation “You have reached the Dublin PSAP. You are located in Citywest Hotel, Saggart County, Ireland.” Security requirements: must have no impact on LoST or call integrity – e.g., munging signed responses no-no Add sentence on user location validation – inherent impact Otherwise done. 7/29/08ECRIT - IETF 72 (Dublin)7