Cisco 7925G Series Deployment Manual page 75

Select the method to submit a certificate request by using a base-64 encoded PKCS file.
Paste the certificate data from the Cisco Unified Wireless IP Phone 7925G Series to the Certificate Authority signing server and
submit for signing.
When the certificate has been signed, download the CA certificate in DER encoded format (base 64 encoded certificates are not
supported).
Ensure Client Authentication is listed in the Enhanced Key Usage section of the certificate details.
Cisco Unified Wireless IP Phone 7925G Series Deployment Guide 75