Exchange limitations for sending multiple calls

Forums › Spark New Zealand (including Skinny and BigPipe) › Exchange limitations for sending multiple calls

Lertinfo

3 posts

Wannabe Geek

#139438 9-Feb-2014 13:31

Hi one and all

Our company currently sends emergency notifications via Txt and email. However the only way to reach isolated communities is by landline.

Does anyone know what the limitations are on the exchanges as far as load is concerned. The messages will be 15 seconds long and are pre-recorded.

We have heard that there was a 10% loading limit years ago ie only 10% of the numbers could connect at any instant.

We may need to get through to 80% so we need to know how much to stagger the calls.

This will be applicable to farmers, and communities that get no cell coverage where they rely on phone trees.

Thanks for your help.

Cheers

Stuart

raytaylor

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#983766 10-Feb-2014 22:47

If they are served off a CMAR system, then a very large area with maybe 100 subscriber lines may have only 10 or 15 trunks available to them.

A couple of communities we put in broadband for now run most of their lines over voip because the local telephone cabinet only had 10 trunks running to it and about 20 houses coming off. So in the evenings when the dialup modems were connected for hours at a time, no one else could make outgoing calls.

These two areas had what I would call a step above CMAR, still microwave backhauled but of a higher quality than CMAR which doesnt generally support dialup so the CMAR areas hardly over flow.

Of course that has changed in those particular areas now that no one is using dialup modems.

Are you targeting general public, or your own staff (like the fire dispatcher calling the firefighters to the station)

A little more on CMAR.
There will be XX trunks running up to a high site. From the high site, its linked to several other sites using microwave point to point links. The smaller sites may cover an area 1-4km in radius from the roadside cabinet, but these little 'pods' can be spread over a 50km2 area. So there is no way of knowing if you are calling someone on a cmar system or not, as there could be PCM cabinets serving other pods between the cmar areas.

So anyhow these cmar pods all link back to the high site where the calls are trunked back to the telephone exchange.
I think the CMAR system is a genius way of doing things and worked well to get rid of party lines, but does have such limitations where calls are transported wayyy out of the area, to the aggregation point before going to an exchange which could be in a different toll local calling area, but its then delivered back to the applicable exchange as the billing point via fibre.

Ray Taylor

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Lertinfo

3 posts

Wannabe Geek

#983844 11-Feb-2014 07:38

Thank you for that detailed reply Ray.

It has answered many questions. I see the main problem coming where we replace terribly outdated and old fashioned phone trees. What may take 30 minutes with a phone tree we could do in 1 minute , while at the same time reaching more of the community. You only need two of the starting point people of a phone tree to not be contactable and all those down line of them don't get the message.

Our service provider can stagger calls and also retry if no reply so that will probably overcome loading problems. What do you think?

Cheers

Stuart

sbiddle

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Biddle Corp

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#983845 11-Feb-2014 07:45

IMHO this is really something you need to be discussing with Telecom on a technical level before you even contemplate deploying such a solution.

Such technical restrictions apply to everywhere, not just some rural areas. Cabinets using VMUX hardware for voice also have limitations.

Lertinfo

3 posts

Wannabe Geek

#983847 11-Feb-2014 07:52

It certainly is something we need all the information as possible on. The challenge is getting to the right person in telecom.

IT's interesting the variety of thoughts on the matter. Outside of Geekzone opinions vary considerably.

Cheers

plambrechtsen

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#983861 11-Feb-2014 08:31

Lertinfo: It certainly is something we need all the information as possible on. The challenge is getting to the right person in telecom.

IT's interesting the variety of thoughts on the matter. Outside of Geekzone opinions vary considerably.

Cheers

I would say your Gen-I business manager would be a good start, since this is no a retail issue / request per-se but more of a medium to large business question so Gen-I are the people I would be directing you to. Flick me an email "pl at telecom.co.nz" and I am sure I can find someone to respond to you depending on where you are in the country.