Can I use an internal root certificate or internal Certificate Authority created by CA Top Secret with TN3270?
Yes you can use a internal Certificate Authority generated by CA Top Secret with TN3270, but it comes at a cost.
3rd party Certificate Authorities distribute their roots to many applications. This saves the user from installing the root certificates.
If you generate an internal root certificate using CA Top Secret, you will need to distribute the root certificate to all the users that will be using it.