Voice quality on UFB

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kramgk

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#106106 18-Jul-2012 10:15

Our street in Napier has just been rebuilt for UFB and NowNZ, aka AirNet, have offered a voice plus data package. I phoned them regarding the voice quality and they said it would be good. I asked what codec they would use and he said G.729, although he wasn't sure. However, he was sure that the POTS line would be connected to their equipment, not the Chorus ONT.

My question is why would a Residential Service Provider choose to use their own Analogue Telephone Adapter when the Chorus ONT has one, and with a G.711 codec? I cannot imagine why I would change to fibre and then have to talk to people with a tin can and string.

Beccara

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#657454 18-Jul-2012 10:21

We use our own ATA's as the integrated POTS ports on the ONT aren't directly accessible to the ISP so diagnostics and configuration updates are a real PITA, If an ISP maintains remote access to the ATA normally for diagnostics and uptime monitoring then moving to the ONT ports would be a downgrade in the service.

As for the codec choice it's all personal really, Alot of our clients can't tell the difference in quality between 729 and 711 and even under MOS scoring 729 is 3.92 max compared to 711's 4.1 max. If 729 is widely deployed on their current network then giving fiber the choice to 711 may introduce transcoding into calls between clients on the network which is not a great thing to have.

Most problems are the result of previous solutions...

All comment's I make are my own personal opinion and do not in any way, shape or form reflect the views of current or former employers unless specifically stated

sbiddle

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#657464 18-Jul-2012 10:31

I would go as far as speculating that the vast majory of ISP's will use their own ATA's/RGW's rather than using the voice port in the ONT.

Why? Because the inbuilt port offers very little configuration or diagnostic capabilities and most ISP's have autoprovisioning models for existing hardware.

kramgk

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#657483 18-Jul-2012 10:55

Thank you for the Ultra Fast Replies. I confess I was put off by the 8Kb/s rate, but the MOS figures are pretty good. An interesting thought that RSP's are looking to deliver voice calls to their own B Party via the IP network rather than just always forwarding the call into Telecom. Step one would be to get enough customers!!

Thanks again for the quick response.

sbiddle

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#657677 18-Jul-2012 14:46

kram9: Thank you for the Ultra Fast Replies. I confess I was put off by the 8Kb/s rate, but the MOS figures are pretty good. An interesting thought that RSP's are looking to deliver voice calls to their own B Party via the IP network rather than just always forwarding the call into Telecom. Step one would be to get enough customers!!

Thanks again for the quick response.

I assume you mean 8 KB/s ? If so this is 64kbps which is the bandwidth requirements for a ulaw/alaw call and forms the basis of existing ISDN and TDM world.

IP peering of voice already exists in NZ between a number of providers. Gone are the days of every call having to transit the Telecom network, although a significant proportion still do.

kramgk

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#658518 19-Jul-2012 15:29

Hi Steve. Thank you for your question as to whether I had mixed up bytes and bits. You have made me do the unthinkable and go and read the manual. A G.729 encoder samples the analogue signal 8000 times per second, which is a good start. After 80 samples, 10mS, it internalises a really complicated situation and spits out 10 bytes. 10 bytes every 10mS is 8000 bits per second.

Beccarra mentioned transcoding and this is a fearful thing. Are RSP's able to transit directly to the mobile phone providers and transcode directly into GSM wireless codecs and/or AMR? In short, what is the quality like when phoning someone on a mobile?