Dead air on calls (both landline & wireless)

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Could there be a problem in the telephone switching system causing incoming and outgoing calls to be just dead air?

I spoke with someone who said when people call their landline, they often get dead air. I proved it with my MTS cell from inside the home. The phone said dialing...connecting...connected, but it was dead air the whole time. Not even the ringing sound. Interestingly, as soon as I hit any number on my cell, the sound came back (even before it's picked up!)

I assume my phone would likely connect to a tower tied to the same telephone office, but I realize there are many factors for what tower a phone picks. So it could be more widespread.

Anyway, I had someone call the number from a competitor's cellphone and it rang right away. Same thing when I tried it from a VoIP app on my phone.

Thanks
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JG, Champion

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Posted 2 years ago

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Clifford Lewis, Champion

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Any idea if this number was "ported" from some other provider, or its a number that was moved from another exchange?  That could explain why incoming calls don't connect from one provider but from another. 

Somewhere  there may be a messed up translation data base at the provider that can't connect.

Even if its not a ported / moved number,  the customer is going to have to put a service call in and somebody at the telco test center would probably have to do a test call and  track the call progress to see where the call is being lost.
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Graham, RF Engineering

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Hi Jesse, can you send the number in question to community@mts.ca c/o me? I'll try to track down the right people, as Clifford mentioned it is probably a translation issue.

If you could provide the situation, i.e. did they just port into MTS? Is it a new line? etc. Ideally the person themselves would send the info as it would probably require their cooperation and/or communication in order to get it resolved.

Thanks
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JG, Champion

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Sure, I'll send it shortly. Just a heads up, I was at her home on a repair ticket (I may not have mentioned it here, but I'm a contractor for MTS) and checked everything over. I even bypassed her alarm temporarily. Her line tested perfect, too. I believe her MTS number is an Edison number ported to Niagara. She's elderly, and very frustrated. Thanks
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Graham, RF Engineering

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Perfect, thanks, with number portability there are a tonne of systems involved both on each operators side and the clearinghouse side that the number has to be erased or readdressed in, I'm guessing one of the systems is still pointing the wrong direction, we'll get it fixed up.
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JG, Champion

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I'd love to see how that works. I know this stuff all takes place in milliseconds, but I wonder if routing can get complicated like this:

Customer is assigned a number from the nearest exchange. They move to an area with a different exchange, but then port out to the competition for a while, and eventually port back.

Does that mean all that routing is just left in place, or does it automatically correct itself to the simplest route? If not, I could see how that could sometimes cause issues.
(Edited)
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Clifford Lewis, Champion

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Wikipedia has a fairly good  entry (https://en.wikipedia.org/wiki/Local_number_portability) on how LNP works and talks about the 4 different ways that a telco can check to find the new destination for a ported number, whether its between exchanges of  the existing provider or between different providers.

I have no idea which one of the 4 searches that MTS uses.

One of my co-workers had ported a Shaw landline to MTS landline and about 2 years ago  decided to port it to Rogers cell and dump the landline.

So far she has not said anything about not getting any calls so the system works.  It apparently took slightly longer to move as internally MTS had to release the number back to Shaw then Rogers had to request  to Shaw that the number be linked to the  Rogers telephone  system. 

All done by the three Telco's  back office staff with no involvement by by my friend other than signing the paper at Rogers to move the number from the existing provider.
(Edited)
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Clifford Lewis, Champion

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Actually call routing between exchanges is a completely different system and depends on call volume, equipment status  etc.

There is an interesting video from the old AT&T system on how they controlled long distance service in North America https://www.youtube.com/watch?v=cigc3hvMyWw

And here is a short clip of their current system https://www.youtube.com/watch?v=lN6BHxDp-rA

And for those that have not seen it here is the MTS NOC

https://www.youtube.com/watch?v=kBCXmeRIaDs
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Graham, RF Engineering

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We've had our translation specialist troubleshoot this link and it all checked out when he tried, Jesse confirmed it is currently working as well. Please let the customer know that if they have this issue in the future to call us asap so we can catch it when it is happening.

Thanks for your follow up with this customer Jesse!
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CoryB, Champion

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Sort of reminds me of the urban legends of how old wire taps used to be horrible and behave similar to this.