Is is possible to join a network without giving other nodes in the network access to my own node? I only need to access the private services on the network, without other having access to the services on my node (eg: ssh).
Node sharing Sharing your nodes with other users · Tailscale allows a node to be shared with another user. That other user will be allowed to connect to the shared node. The shared node will not be allowed to connect to anything.
I think what you ask can be achieved if that other network shares the nodes with you.
Right now, the available mechanism to access nodes on a tailnet you are not a member of is to have those nodes be shared with you. There may be other mechanisms in the future, but node sharing is the one available today.