Server Name Indication (SNI) helps to efficiently use IPv4 resources and provides the following benefits:
You can run any number of SSL sites with independent certificates on a single IPv4 address.
You can install independent SSL certificates on each of your sites. Now, there is no need to create another subscription. Each subscription can install an SSL certificate even if there is only one shared IP address on the whole server.
Wildcard SSL Certificate helps while having multiple subdomains.