CCNA - CCNP Instruction - IPv6 Addressing

As a CCNA/CCNP candidate you are envisioned to recognize IPv6

In the course of your job as a Cisco community engineer you will have to deal comprehending IPv6 address composition.

For your CCNA and CCNP reports you have to at some position confront and understand IPv6. At ccnp boot camp uk can see fairly complicated in contrast to IPv4 that we are all employed to, in true simple fact IPv6 is very a simply addressing protocol once you get previous the original shock. In this post we are heading to have a appear at Neighbour discovery protocol for layer 2 mapping.

When an IPv6 host or router demands to send out a packet to some other host on the identical network it will first of all look into it truly is own neighborhood neighbour databases to uncover if it has an IPv6 to MAC mapping, if it finds the right mapping the host will use it, if there is no mapping the host will need to have to resolve the recognized layer 3 IPv6 address to a at present unidentified Layer 2 MAC address and to do this the host employs the Neighbor Discovery Protocol or NDP to learn the MAC address dynamically.

The Sending host will use a multicast message referred to as a Neighbor Solicitation (NS) icmp information to ask the receiving host for it really is MAC deal with, the obtaining host will reply with a Neighbor Advertisement (NA) icmp information unicast in return with the requested MAC handle.

How IPv6 achieves this is all in the design of the Neighbor Solicitation concept which helps make use of a unique IPv6 destination address known as a "Solicited Node Multicast", this solicited Node Multicast at any provided minute represented all of the IPv6 hosts on the link, the previous 24 bits of the Solicited Node Handle are the previous 24 bits of the IPv6 tackle of the gadget that a host is requesting the MAC from.

The IPv6 multicast location address is FF02::one:FF:/104 the ultimate 24 bits are created up of the very last 24 bits of the IPv6 deal with to which the concept is currently being sent to. For illustration if a host needed to find out the MAC deal with of an IPv6 host dealt with as 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/sixty four then the solicited Node Address will seem like the pursuing FF02::one:FF:CC:DDDD/104


When a sending hosts needs to get the MAC handle from the IPv6 host of 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/64 it will just take the previous 24 bits of the known IPv6 deal with and location them into the remaining 24 bits of the Solicited Node Deal with and since all IPv6 hosts listen to their possess Solicited Node addresses, when they listen to their deal with they will reply with the MAC tackle.