There is no whitepaper, since that is not a supported phone. It would have to be configured as Generic SIP.
Looking at Asterisk forums, folks have a real hard time getting that phone to work with Asterisk, too.
Have you tried using TCP as the protocol for those phones? UDP doesn't seem to work with SIP systems for the 9608.
Make sure you have a Phone Trunk set up for whatever protocol you are using with those phones. I don't know what to tell you for settings on that trunk...I've never tried to get an Avaya phone to work with PureCloud (or PureConnect).
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George Ganahl CCXP, GCP
Principal Technology Consultant
Genesys
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