1) IPv4 32 bits , IP v6 128 bits
2) No address collision
3) no need for DHCP
4) more efficient routing
5) Ipv6 fixed 40 Bytes of header, 32 bytes are source and destination address.
How IPv6 Get IP:
1) fe80:: used by default
2) stactic IP
3) DHCPv6, send out UDP mutilcast to port 547
4) Stateless Address auto configuration , device auto learn the prefix of ip address from the router\'s response .