Tunneling is commonly used in several transition mechanisms. Some of the mechanisms discover the tunnel endpoint automatically by their own means. This paper describes several tunnel discovery mechanisms for IPv6 traversal beyond IPv4 legacy networks and suggests a new mechanism by which the DHCPv4 server can automatically provide configuration information about IPv6-in-IPv4 tunnel. Dual stack nodes attached to IPv4 network can communicate with other IPv6 networks by this mechanism beyond IPv4 networks without user intervention. Implementations have shown that the proposed mechanism can be a convenient and valuable tunnel discovery mechanism in some cases.