A peer can authenticate itself towards a network with its RSA key,
which can be managed from the client interface. The authentication status of
trusted (auto) by default. This means that peers
can interact with each other since the client automatically authenticates and
trusts the connecting peer.
You can manually authenticate peers by blocking new network members
from establishing connection to your client.
Note: This functionality is not available on Linux.
Go to the
System > Preferences > Security
Block new network members by default option.
The status of a blocked network member becomes
Authenticate the peer, for example by asking him to send you his
public RSA key.
Chatting with untrusted peers is possible in Hamachi, but you
cannot establish a network connection to them.
Right-click on the name of the peer and select
Trust > Trusted.