IPv6 is not backwards compatible with IPv4
Dual IP Stack
IPv4 + IPv6 on the device. Can be used independent of each other
IPv4 Mapped Addresses
Map IPV4 address to IPv6
First 80 bits are 0 next 16 bits are 1 (shown as ffff) and last 32 bits are populated with IPv4 address
e.g. ::ffff:192.168.1.100
Tunneling
IPv6 packets are encapsulated in IPv4 datagram
Microsoft uses an special adapter called as Teredo to achieve Tunneling