Connecting to automated modem through SPA122 ata

[jlevine02]

We have an SPA122 ata that is connected to a modem that the utility company uses to read our utility meter.  I am able to make calls ingoing/outgoing with an analog phone, but when connected to the modem on our utility meter it is not communicating correctly.  Are there any recommended settings that can be suggested to improve comunication.  

The modem sounds that it answers but then hangs and disconnects.  Doesn't do proper modem speak

Thank you

[Dan Lukes]

1. uncompressed codec must be used
2. set RTP Packet Size to 10
3. Network Jitter Level should ve set to very high, Jitter Buffer Adjustment turned off
4. modem speed must be configured to 9600Bd max, modulation V.32
5. end-to-end RTP path during the data call must be reliable with low jitter

Note that compressed codec MUST NOT be used anywhere on the path. So be sure your upstream provider doesn't use compression with it's next-hop provider. Audio format transcoding should be avoided. So select appropriate G.711 variant (aLaw or uLaw) on your side.

If your end-to-end connectivity is very high quality you may try to use 14400Bd speed. Even in such case you should prefer V.32 over V.34 modulation. Configure yours modem accordingly.

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