Here’s a topic I wrote about Sentinel. It’s the part of the network where you get above the ip-address layer. The network will give you an address in XOR-space. It’s take it or leave it. If you take it you now have 31 new friends in XOR-space. If you say to them, I own 12 Safecoin, they’ll just watch the address of your coins. When you sign that message using a private key, they’ll all see that you are indeed the owner of these coins. If you sign a message to sent it over to another address, they confirm that request. they reach consensus on the fact you signed a message saying you want to move 3 of the to a different address.