user12893: After going through the bitcoin protocol documentation it is still unclear to me how the bitcoin client is authenticated. Where can I find an overview of what the client sends and receives on the wire during authentication?

user12983: There is no "authentication" in bitcoin protocol. It is not encrypted also. 
You can use wireshark to investigate handshake packets

12893: <p>After going through the <a href="https://en.bitcoin.it/wiki/Protocol_documentation" rel="nofollow">bitcoin protocol documentation</a> it is still unclear to me how the bitcoin client is authenticated. Where can I find an overview of what the client sends and receives on the wire during authentication?</p>
 12983: <p>There is no "authentication" in bitcoin protocol. It is not encrypted also. </p>

<p>You can use wireshark to investigate handshake packets</p>
