What type of tunnel should be used in this case?

RouterOS General
1

Hello,
What type of vpn tunnel should be used in this case:

  1. server and clients are Mikrotik routers.
  2. server have public ip address.
  3. all clients have private ip addresses (behind nat).
  4. some clients behind same nat (l2tp+ipsec do not work in this case).
  5. MPPE encryption or certificates should not be used.
  6. tunnels should have interfaces.
2

Use SSTP …