Hi,
PTP feature is fully supported from SEP 12.1 on Server operating systems.
You can use either NTP (Network Threat Protection) or Windows firewall on server operating systems.
We do recommend to use NTP feature on server operating system & make necessary port exceptions if required.
Can refer this article as well:
Best Practices for Installing Symantec Endpoint Protection (SEP) on Windows Servers
http://www.symantec.com/docs/TECH92440