DPOD Syslog agents use TCP (not UDP) in order to deliver reliable connection. The agents do not support an encrypted tunnel (SSL / TLS) yet - support is planned in a future version.
In the meantime, if encrypted connection is required, it is possible to use external tools to proxy DPOD agents (e.g.: the open source tool https://www.stunnel.org/index.html which is published under GNU GPL license).