I want to deploy my application with following domains:
domain.com, www.domain.com - no ssl required, static pages only
sub.domain.com - ssl required
Can I buy SSL cert only for sub.domain.com or do I need to buy wildcard cert for my case?
The short answer is: Yes you can. The item you need to look for is Subject Alternative Names (SANs) you can purchase one of these from VeriSign, from 1-3years.
Hope this helps you!