IPv6

IPv6 addresses are 128 bits long, split up into groups of 16 bits which are represented by 4 Hexadecimal digits seperated by a : . Continous double octet groups with only 0000's can be replaced with :: .

An address is broken down into 3 parts, the Network Address, the Subnet Address, and the Device Address.

The Network Address is the first 48-bits of the address which is the first three blocks of four hex digits.

The Subnet address is the next group of 16 bits or one double octet.

The device address is unique to the host and comprises the rest of the ipv6 number, 64 bits or four blocks.

Example:-

Allocation split in to two large subnets.

Network Address
48 bits
Subnet
16 bits
Host Address
64 bits
Network
Length
2001:08B0:FF92 0000 0000:0000:0000:0000 /48
2001:08B0:FF92 1000 0000:0000:0000:0000 /52
2001:08B0:FF92 0100 0000:0000:0000:0000 /56
2001:08B0:FF92 0010 0000:0000:0000:0000 /60
2001:08B0:FF92 0001 0000:0000:0000:0001 /64

Subnet Binary 1000-0000-0000-0000 = 0x8000 hex

Network setup:-

+---------+               +-------------+    Red Net       +----------+
|Internet | ------------- | Adsl Router | ---------------- | Firewall | -- Internal Green Network
+---------+         ppp0  +-------------+  eth0            +----------+
                                                                 |
                                                                 +-------- DMZ Network

Tentative example:-

adsl ppp Autoconf by ISP
adsl eth0 2001:08B0:FF92:0011::1/64
Firewall Red 2001:08B0:FF92:0011::2/64
Firewall Green 2001:08B0:FF92:0012::0001/64
Firewall DMZ 2001:08B0:FF92:0013::0001/64
Host - Green 2001:08B0:FF92:0012::0010/64 onwards
Host - DMZ 2001:08B0:FF92:0013::0010/64 onwards

Static routes on router:-

Red is locally connected, so no static route needed.

Green 2001:08B0:FF92:0012::0000/64 via 2001:08B0:FF92:0011::2
DMZ 2001:08B0:FF92:0013::0000/64 via 2001:08B0:FF92:0011::2

rb/ipv6.txt · Last modified: 10/10/2013 15:21 (external edit)