Hello Kevin,
The Resource Center has a comprehensive guide on setting up your desired telephony configuration. For this one in particular, the article
Create a trunk under BYOC Cloud should provide you step-by-step instructions.
I highly advise reading through the larger
BYOC Cloud section - this is the telephony configuration you are trying to implement with the Vonage SIP Trunk solution. It will help a lot if you reference future questions based off the guides here.
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Nico Feliciano
Genesys - Employees
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