IPV6 concepts

IPv6 conventions use 32 hexadecimal numbers, organized into 8 quartets of 4 hex digits separated by a colon to represent a 128-bit IPv6 address. ( a quartet is one set of 4 hex digits in an IPv6 address) Two ways to simplify the expression of IPV6 address:
+ Omit the leading 0 in any given quartet
+ Represent one or more consecutive quartets of all hex 0s with “::” but only for 
    one such occurrence in a given address.

Prefix Terminology


Assigning IPv6 Global Unicast Address

imageStateful DHCP for IPv6
IPv6 Client send multicast (not broadcast in IPv4 world) searching fro IPv6 DHCP server, which in return reply with IPv6 address, prefix length and DNS IP address. IPv6 DHCP server does not provide default router information as that relies on Neighbor Discovery Protocol between IPv6 client and local routers.
DHCPv6 servers have two different operation mode: Stateful and Stateless
IPv6 multicast address prefix: FF00::/8, and FF02::1:2 is used for IPv6 client to search for DHCPv6 servers.
Stateless Auto-configuration
it allows IPv6 clients to automatically learn the key information for IPv6 addressing, prefix, prefix length, default router, as well as DNS IP address. detailed process is as below:
+ IPv6 client multicast Router Solicitation (RS) to FF02::2 which mean all routers
   on this LAN, to obtain prefix, prefix length, default router address. Then Router
   Advertisement (RA) are multicast by routers on that LAN to FF02::1 (all IPv6
   nodes in that LAN) as an reply to RS.
+ As Subnet Prefix is 64 bit long, we need another 64 bit for host ID. EUI-64 is
   utilized here to insert FFFE (16 bits) in the middle of MAC address to form a
   64 bit host ID. (1234:5678:9ABC to 1234:56FF:FE78:9ABC)
+ Finally, IPv6 client use Stateless DHCPv6 to learn the DNS server IP address.
To be Continued