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> For VoIP, Amplitude distortion and quantization error (from multiple sources) means you will never get 56k over any voip system https://frank.petril.li/posts
by FrankPetrilli 3y ago
> For VoIP, Amplitude distortion and quantization error (from multiple sources) means you will never get 56k over any voip system
https://frank.petril.li/posts/dialup-adventures-1/ https://frank.petril.li/posts/dialup-adventures-1/
I've done V.90 over VoIP. In a very controlled environment that was tuned for it, but VoIP nonetheless. The main issue is that VoIP timing, even with deep buffers, is prone to more jitter than a PDH network and the phase drift will eventually cause enough errors to force a retrain every few minutes. Either way, "never" is a little too absolute IMHO. :)
- epcoa 3y agoFair enough. How about V.92? Have you had a setup where upstream PCM could be successfully established?
- FrankPetrilli 3y agoGood question - it's been almost two years since this project so I don't recall whether V.92 came up at all, even on a pure T-1 setup. I still have all the gear, if I set it up and run it again I'll update this thread.
- simfree 3y agoWhat gear were you using?
- FrankPetrilli 3y agohttps://frank.petril.li/posts/dialup-adventures-1/ https://frank.petril.li/posts/dialup-adventures-1/ explains it all!
- simfree 3y agoAny chance you would be bringing that modem bank to ToorCamp on Orcas Island? The ShadyTel network could always use a better, faster dialup ISP!