3.1.b Identify, implement and troubleshoot IPv6 addressing and subnetting

3.1.b [i] Unicast, multicast

IPv6 addresses are represented as a series of 16-bit hexadecimal fields separated by colons (:) in the format: x:x:x:x:x:x:x:x.

Following are two examples of IPv6 addresses:

2001: DB8: 7654: 3210: FEDC:BA98: 7654: 3210

2001: DB8: 0: 0: 8: 800: 200C: 417A

It is common for IPv6 addresses to contain successive hexadecimal fields of zeros. To make IPv6 addresses less cumbersome, two colons (::) may be used to compress successive hexadecimal fields of zeros at the beginning, middle, or end of an IPv6 address (the colons represent successive hexadecimal fields of zeros).

A double colon may be used as part of the ipv6-address argument when consecutive 16-bit values are denoted as zero. You can configure multiple IPv6 addresses per interfaces, but only one link-local address.


 ipv6 address types

An IPv6 address must be configured on an interface for the interface to forward IPv6 traffic. Configuring a global IPv6 address on an interface automatically configures a link-local address and activates IPv6 for that interface. Additionally, the configured interface automatically joins the following required multicast groups for that link:

● Solicited-node multicast group FF02: 0: 0: 0: 0: 1: FF00::/ 104 for each unicast and anycast address assigned to the interface

● All-nodes link-local multicast group FF02:: 1

● All-routers link-local multicast group FF02:: 2

IPv6 redistribution ignores the “local” routes in the IPv6 routing table (the /128 host routes for a router’s own interface IPv6 addresses) whereas IPv4 has no such concept.

Adam, Paul (2014-07-12). All-in-One CCIE V5 Written Exam Guide (Kindle Locations 2276-2285).  . Kindle Edition.