Damian wrote: > 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?
Anyway, you can configure a Polycom with two entries for the same server, the first being FQDN and the second being IP. If the FQDN resolves to multiple SRV records for traffic load and/or fallback, then we would want to include all the IPs. > > 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. I'll raise a JIRA for the Polycom plug-in. This would mean a DNS lookup of emergency gateway FQDNs when the profile is generated. What about the SRV case? It would be nice to take the priority of each record into account. > > 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_Stan > > d- > > > 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). Companies with large buildings or campuses may want to have a non-standard emergency number. When help arrives at the front door, someone from the company needs to be ready to lead the way to the emergency. Allowing for the extra 9 is probably solely as a safeguard against mis-dialing. > 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. An emergency number that is internal to sipXecs, which triggers the Emergency Dial Rule... It can be done, but it is ugly. You need to configure a loopback unmanaged gateway, and use it in the Emergency dial rule. The rule's "Emergency number" value would then be the internal target. The number that users dial in an emergency would then need to include the rule's PSTN prefix. (If the PSTN prefix is omitted then the target will be reached directly, without triggering the rule, and thus no alarm email.) But for 4.0 we should advise against using an Emergency Dial Rule for an internal emergency number. (So no alarm email for internal emergency numbers.) Or did you mean an emergency number that is internal to the company, but external to sipXecs, and routed differently than other calls? > 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. Perfect. Update on the LG-Nortel port, these phones can use only 5060. I'll open a JIRA to hide the emergency_address_port. This is a simple change, so I'll set it for 4.0 unless there are objections. This is a big problem in the unlikely event that the Emergency Dial Rule's gateway requires a port other than 5060. You will need to manually override sipXconfig's automatic gateway dialing content in the LG-Nortel phone profiles, otherwise emergency calls will fail. I will include this detail in the Wiki. We could fix this problem in sipXconfig by suppressing automatic gateway dialing when the port is not 5060. Any objections to a JIRA for that? We may require similar handling on our side to account for XTRN-488: LG-Nortel 68xx can't handle the emergency_address in FQDN, only as IP address. -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
