When you use the DES automated provisioning to deploy the J100 SIP IP Phones, DES provides the phone provisioning URL. You can optionally configure DES to provide the Private Trust Root CA Certificate during the DES automated provisioning flow. For more information about configuring DES for automatic provisioning, see Using Avaya Device Enrollment Services to Manage Endpoints_R31

For example, in a deployment scenario where DES provides the provisioning server address to the phones, the phone connects to the server, and the server presents a server identity certificate signed by a private CA. The phone will have the Private Trust CA Certificate required to trust the provisioning server identity certificate.