(I'm going to use the term SSL, as that is the common way for describing this stuff even if it isn't technically correct.)
Interesting about the one IP per certificate issue/discussion. This was often the case, and Linode still accept using a trusted signed HTTPS SSL cert as justification for another IP address, but for many years it has been possible to serve multiple SSL certs on different domains from a single IP address. This is known as Server Name Indication (SNI) and works under Apache and IIS and other popular web servers that support TLS. It seems the major pitfall is that it isn't supported on any XP compatible version of IE, but I'm not sure that really matters to many of us in 2015.
I have never actually used this - I still use 1 IP per cert, but has anyone any real life experience of SNI they care to share?
Good article here:
https://www.digicert.com/ssl-support/ap ... ng-sni.htmChris