Paul Mossman wrote: > Scott wrote: >> On Fri, 2009-04-03 at 17:12 -0400, Andy Spitzer wrote: >>> Woof! >>> >>> On Fri, 03 Apr 2009 16:35:06 -0400, Scott Lawrence >> <[email protected]> wrote: >>> Marten: >>>> No CDR, no alert >>> Scott: >>>> which is a significant improvement over the proxy being >> down and no >>>> ambulance. >>> Okay, enough bitching. >>> >>> Is there a way to provision the phones to try the proxy >> first, then go >>> direct it that doesn't work (best of both worlds?) >> well, we could do that with an 'emergency' SRV record 1/2 :-) > > Polycoms allow multiple emergency servers to be defined, so it is > possible without SRV. But sipXconfig currently only generates config > for the first server, so additional implementation would be required.
Just to make sure: the SRV 1/2 thing is a joke right? > > Also Dale makes a good point that phones should fallback to an IP > address, in case the DNS server is down. > > LG-Nortels on the other hand have only one emergency server. > Furthermore the config only accepts an IP (not FQDN), so SRV is not even > an option. Using a port other than 5060 doesn't seem to be an option > either. I'm waiting for clarification from LG-Nortel on these, but > doubt it will change before 4.0. > If the phone does support multiple outbound proxies for 911 calls, and if those are always tried in the same order, and if fallback is predictable - then yes: it does solve many problems. There is nothing in sipXconfig today that prevents the phone plug-in from implementing E911 routing on the phone to try sipXecs proxy, 'emergency' gateway and the IP address of the 'emergency' gateway. > > While we're on the topic, there's a limitation in the sipXconfig > automatic gateway dialing functionality itself. The Emergency Dial Rule > contains an (optional) PSTN prefix, so both 911 and 9911 trigger the > rule. As we have been discussing, Polycoms and LG-Nortels are at this > point automatically configured to send 911 calls directly to the > gateway. But 9911 calls will always be sent via the proxy, which is > inconsistent, and therefore probably a bad idea. > > Polycoms and LG-Nortels could be configured to send 9911 directly to the > gateway with phone profiles changes. Of course the gateway would > require configuration in order to strip the 9 and dial 911. For an > Audiocodes this must be done directly in that gateway's Web UI, since > this configuration is not handled by sipXconfig. > > Here's how you'd do the configuration in the Audiocodes Web GUI: > http://sipx-wiki.calivia.com/index.php/HowTo_configure_AudioCodes_Stand- > Alone_Survivability_Feature#AudioCodes_Gateway_IP_-.3E_Tel_Destination_N > umber_Manipulation > > (In defense of sipXconfig, the need to configure these settings only > arose a few weeks ago when we started looking at the Audiocodes SAS > feature.) > > On the other hand, both Polycoms and LG-Nortels do allow configuration > that would have the phone strip the 9 from 9911. The phone would send > only 911, so no gateway configuration would be required. This would > also need additional sipXconfig implementation though. Probably not for > 4.0, but maybe for 4.2? Any objections to a JIRA for this? (Damian?) > I'd like to know more about why people/companies employ non-standard emergency numbers. If this is a safeguard against mis-dialing ("what am I to dial - 9-911 or 911 if always dial 9 to make external calls" - then gateways should be configured to strip extra prefix). However if an alternative number is routed differently (some companies want to have "internal emergency numbers") than clearly we do not want phones to send such calls to the gateways directly and no amount of gateway configuration would help. I think we can try to improve UI (either by modifying the emergency rule UI or by adding a separate page) to make it obvious to the admin that sipXconfig will configure endpoints to bypass proxy for emergency calls. Admin should be able to specify which numbers will be treated as 'direct' emergency numbers - all other numbers in emergency rules should just follow standard routing. Maybe admin should even have the option to tell the sipXconfig to refrain from doing that: so that CDRs and alarms for emergency calls work if admin considers it more important. By 'sipXconfig improving UI' I mean of course that plug-ins will be able to get more precise information about what constitutes an 'emergency' call and how administrator wants it to be routed. And of course if phones have ingenious ways to route such calls: even better. > > So we have some issues. At some point we'll figure out what (if > anything) we're going to change for 4.0. Once we do, I think we should > make sure the issues are well documented. > > I'm offering to do the first draft of a Wiki page on this We can then > review it on this list to make absolutely sure its correct. > > Sound good? > Excellent. > > -Paul > [email protected] > > _______________________________________________ sipx-dev mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-dev Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-dev
