CertiGuide to Network+  9  Chapter 0101:  TCP/IP

XVI  Classless Inter-Domain Routing 1 2 3 4 XVIII  CIDR and IPv6

IPv6 Mixed Notation

Since the world is still mostly using IPv4, it may prove to be more convenient when contending with ta mixed Ipv4 and Ipv6 environment to deal with a convention that address both realities. That convention, called mixed notation, deals with six high-order 16 bit places of the address using x, and the Ipv4 representation using d as in the example below, for the lower-order. The convention would look like:

x:x:x:x:x:x:d.d.d.d

For example the private Class A address 10.0.0.1 in Ipv4 would look like 0:0:0:0:0:0:10.0.0.1 in Ipv6. In compressed form it would be ::10.0.0.1

Another example could be 0::FFFF:192.168.0.1

While it may seem a bit confusing at first to have options in math expressions, it sure saves quite of bit of time and reduces the odds for errors. With addresses that are 128-bit in length, and in hexadecimal, think of what writing a subnet mask would look like in the Ipv4 convection of Class addresses!

XVI  Classless Inter-Domain Routing 1 2 3 4 XVIII  CIDR and IPv6