T48 provision with HTTPS

[Fox_snow]

There are some T48 phones . I want to provsion them with multual authentication HTTPS . I find a document (Using Security Certificates on Yealink IP Phones_V72.1.pdf ) . It says that there is a build-in certificates in your phones . I guess whether it is possible that I can do multual authentication HTTPS provision witout update the client certificate file for every phone . If possible , how can I do it ? Is there a introduction document ?