"CNF CONFERENCE CALL"

[tjcurcio]

Hey everyone,

3300 tech here, total 5000 newb

I have a customer who has one phone that rings several times everyday with "CNF Conference Call" on the display.  When they pick up the call there is no one on the other line.  I don't see any feature codes that could have been mistakenly enabled that would be causing this.., so I'm guessing its related to the 5000's internal conference bridge.

Has anyone encountered this and can point me in the right direction?

Any help would be much appreciated!

[Tech Electronics]

tjcurcio,

My guess would be that the person getting this is always the same person and that person is either x1000 on an IP-Based System or PLID 1.1.1 on a Digital-Based System or they are the Primary or Local Attendant for the entire system.

When a conference call is unsupervised for a period of time the system will send the call to the System Attendant, designated by any of the 3 scenarios above, and it will flash their Conference Button if they have it, but the display will show what you Conference Recalling and not CNF Conference Call, but they may have changed that.

There are two places this Unsupervised Timer shows up depending on how the Conference was created.

1. System > Timers > Unsupervised CO
Because loop start trunks frequently do not provide supervision, unsupervised trunk-to-trunk calls (such as unsupervised conferences and forward to an outside number), are limited by the Unsupervised CO timer. When this timer expires, the call recalls the primary attendant who can determine whether the trunks are still in use or if the call should be disconnected.  If the trunk connections are ground start or DID trunks, this timer is not needed as they supply reliable disconnection signals.

2. System > Meet-Me Conferencing > Unsupervised Conference : Although this has changed to allow the users to press a number and if they don't it hangs up on them.

Thanks,

TE

[tjcurcio]

Thank you for your kind and detailed reply!

I think we are on the right track here, as after going on site and witnessing this myself I can confirm that "unsupervised" shows on the display of the ringing phone.

However.. this does not appear to be happening in sequence with either of the timers you listed in your post.

Is there a way to simply disable this (the customer is a restaurant and does not use the conference feature), or to clear this unsupervised conference?

[dwayneg]

You'll also see this if a call is transferred to an outside number (you call and ask for Jeff and I transfer you to his cell, or I transfer you to an off-site number for credit check).  Easy check for this: extend the unreasonably short UNSUPERVISED CO timer from its short 5 min default to 60 minutes or so (System/Timers and Limits).  This timer is a carry-over from the old days when LD was very expensive and CO disconnect supervision was not very dependable.  Note: this MAY be an employee scamming the company by transferring a friend to an outside LD number unbeknownst to management, maybe check call logs.

[Tech Electronics]

Tjcurcio,

Also, this happens with Dynamic Extension as the calls are being conferenced off site to the person's cell. I assume since it is a restaurant they have POTS and the disconnect supervision may not be on the line. Check all the lines for positive disconnect.

Thanks,

TE

[tjcurcio]

Dwayne you nailed it.  I worked with Mitel tech support and it is an outside caller calling in, dialing an extension that is forwarded out to a users cell phone.

I've verified with the carrier that CO Disconnect Supervision is enabled.  So now I'm wondering if this is an issue with the PBX or the carrier.

Tech-- you mentioned: "Check all the lines for positive disconnect."  How can I test this?

[dwayneg]

Your problem MAY NOT be due to disconnect supervision, haven't seen that problem in years.  I'd be more inclined to think it's a perfectly normal call where they speak longer than the default 5 minutes causing it to recall, see if bumping that timer up helps.  If not, try this: Create a Call Routing Application, maybe with a courtesy announcement, that has Digit Translation/Timeout as HANGUP.  Create a System Forwardin path to this CRA.  Then within the forwarded ext try setting this sys fwd path to run under condition CO RECALL...haven't tried this yet, but I suspect it will work.

[Tech Electronics]

Tjcurcio,

We still have this issue in rural areas which is why I brought it up since you stated no one was on the call when the attendant answered it.

Positive Disconnect or Open Loop Disconnect is determined with a volt meter.

Put your meter on the line and set it to check DC voltage. Make a call to the line from your cell and answer it from a system phone. Have the cell phone hang up and see if the meter goes to 0 volts right after that. If it does then you have supervision on the line and the system will see it if it lasts for up to 800 ms. It really takes less than a second for this to happen so you have to pay attention to the meter; if you have a test set on it you may hear a popping noise.

If it does have supervision then I am not sure as to way the call would have no one on the other end when it rings in to the attendant; unless they Hangup during the transfer to the attendant. Maybe Dwayneg would have an idea on that one.

Thanks,

TE

[tjcurcio]

So that may be the key.  I've verified with the carrier that disconnect supervision is enabled, but their Forward Disconnect Delay Timer (this timer controls the amount of time voltage is taken off the line to signal a disconnect) was only set to 250ms.  I had them increase this time 750ms... but per your message it seems I should request to have it increased to 800ms.

[tjcurcio]

Also Dwayne, I'm going to max out that timer, and see if that helps.  This could certainly also be the issue.., as I placed a few test calls today and wasn't able to duplicate the issue, but I didn't keep the "unsupervised conference" open for more than 5 minutes.