Re: [Ecrit] country specific emergency URNs

[Ivo Sedlacek <[e-mail]>]

Hello,



my view:



1) an operator deploying a SIP based mobile network needs sos URNs for every emergency service defined in the country of the SIP based mobile network. Those SIP based mobile networks are being deployed today so the sos URNs are needed *NOW* as those sos URNs is used in those SIP based networks for internal routing (even if PSAPs are still using circuit switched technology).



2) it is regulator's decision on what emergency services are offered in a country.



3) if a service is defined as an emergency service by a regulator of a country, there has to be a unique (within the country) sos URN for it.



4) it is regulator's decision on what sos URN to use to indicate an emergency service.



                NOTE: without such decision, operator can guess an sos URN for a service. However, if guessing is incorrect, the operator will need to re-configure the SIP based mobile network (and that one reason for defining sos URNs relying solely on country identification and emergency number identification).



5) so far regulators are not used to make decisions described in 4).



6) it is decision of a regulator of a country A and a regulator of a country B, whether an emergency service X offered in country A is the same as an emergency service Y offered in country B.



7) so far regulators are not used to make decisions described in 6).



8) imagine that a number (e.g. 123) is specified by a regulator for a particular emergency service.

                Let's assume that someone would register a sos URN with a descriptive sublabel for this emergency service and this sos URN would be used in networks.

                Now what to do if the regulator extends the scope of the service associated with this number (i.e. 123)?

                Would someone need to register a new sos URN (with sublabel reflecting the extended scope) and the networks would need to be reconfigured to stop using the old sos URN and start using the new sos URN?



So, I support Vasil's and Roberto's suggestion to specify a sos URN containing country identifier and emergency number (e.g. urn:service:sos.country-specific.<country ID>.<emergency number> or possibly urn:service:sos.country-specific-<country ID>-<emergency number>). Such sos URN will never be used by the UE (with exception of INVITE request triggered by 3xx response), only within the networks.



All the above probably looks unreasonable or over-engineering from US perspective where 911 is the only emergency number. However, that's how it is in real world in other continents and technology needs to support the real world there too (and trying to force changes there will not be successful).



Kind regards



Ivo Sedlacek



PS: Sorry for commenting late - I was enjoying holidays.