The very nature of the POC provides a significant amount of security as traffic is filtered through multiple routers that restrict incoming connections. The data also has to pass through the PC itself which limits direct access to your sub-network and helps to prevent anyone outside your network from peering in.

It's kind of like tinting the windows of your car except you're tinting the windows of your network in so much as - you can see out, but they can't see in.

There are programs like SMAC available for Windows that allow you to "spoof" the MAC address of your network interface to remain anonymous on parent networks when applicable. This isn't really required for the average user.

Something that may be more useful to the average application is to make use of a VPN client to encrypt the data between your POC and the internet.
By establishing and sharing a VPN connection you are creating a tunnel for any devices connecting through your POC to by encrypted without any configuration - all or just part of the time.

There are programs available such as Wire Shark that you can install on the POC to monitor and even log any traffic that passes through your POC.