sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Telecom Service & Providers 911 Trunking From 5ESS

Not sure it this is the right category for this question. I’m looking for some C.O. help. It has to do with 5ESS and E911. A tech I used to work with said they had failures on both 911 trunk groups (SS7) from a local 5ESS. The calls to 911 went to busy. I questioned him on this thinking that it was probably reorder but he was told busy. This tech is not a C.O. type. He maintains the 911 equipment and he very knowledgeable.
His question to me was he there any fail over that would route the 911 calls to a local POTS number in the event of a duplex failure. I know is the Optical Remotes there was a standalone feature that would route 911 calls to a POTS number if the ORM went into standalone but I don’t remember anything similar for the Host switch. That was 9 years ago. I didn’t know if any of the C.O. guys would have any ideas on this. I suggested assigned a route index to point to an announcement trunk that could direct callers to a local fire house number.
Any help that you can provide to this tech will be greatly appreciated.

I'm not overly familiar with 5E switches, but from a general CO tech standpoint, I would ask if the switch is indicating that the trunks are either locally or remotely blocked, if the T1 carrier is looped somewhere and/or if the CICs & DPCs are correct. Trapping SS7 messages on the links is probably worth doing.

Thanks for the response. I'll pass this on.

Well, I'm probably going to show my ignorance, but...
As I remember it, SS7 has to do strictly with LD calls and I think 911 calls are strictly local.
Having said that I will further get out on a limb.
When a group of trunks cannot complete calls due to a failed destination trunk, calls are routed to a "fast busy". That's totally different than a regular busy in that a phone guy would know immediately that this is a trunking issue and not an all circuits busy issue.
Of course calls could theoretically be routed to a fail over trunk which would then ring to the fire station.
In the old days all sorts of alarms would be going off in all sorts of offices if the 911 calls were unable to complete and the issue would be resolved in minutes, some way or another.
I'm betting a really big cup of coffee that there was a cable cut going into the 911 center.

No, these are SS7 trunks groups. The 911 center is not in the same wire center as the switch that experienced the failure. Thanks for the response.

Nowadays....CO switch to CO switch TDM trunking is SS7....be they local or long distance.