Don't deploy IPv6 on internal networks!!!
According to the German researcher Marc Heuse, businesses shouldn't deploy IPv6 on internal networks, particularly as the protocol is still full of vulnerabilities. Marc, who knows IPv6 inside out, affirms that the present vulnerabilities in IPv6 could lead to man-in-the-middle attacks, password sniffing and packet tampering. He suggests that businesses should only consider deploying IPv6 for Internet facing services for the time being!