As a CCNA/CCNP prospect you are expected to comprehend IPv6
In the course of your profession as a Cisco network engineer you will have to deal understanding IPv6 tackle structure.
For your CCNA and CCNP studies you have to at some point confront and comprehend IPv6. At first glance it can see really complicated compared to IPv4 that we are all used to, in genuine reality IPv6 is really a just addressing protocol when you get previous the initial shock. In ccnp training are heading to have a look at Neighbour discovery protocol for layer two mapping.
When an IPv6 host or router wants to ship a packet to some other host on the same network it will 1st of all appear into it is personal neighborhood neighbour databases to locate 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 three IPv6 handle to a currently unfamiliar Layer 2 MAC handle 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 concept named a Neighbor Solicitation (NS) icmp message to ask the receiving host for it is MAC handle, the receiving host will reply with a Neighbor Advertisement (NA) icmp information unicast in return with the asked for MAC tackle.
How IPv6 achieves this is all in the building of the Neighbor Solicitation message which helps make use of a unique IPv6 destination address referred to as a "Solicited Node Multicast", this solicited Node Multicast at any offered instant represented all of the IPv6 hosts on the website link, the last 24 bits of the Solicited Node Deal with are the very last 24 bits of the IPv6 deal with of the gadget that a host is requesting the MAC from.
The IPv6 multicast spot address is FF02::1:FF:/104 the closing 24 bits are produced up of the final 24 bits of the IPv6 deal with to which the concept is becoming despatched to. For example if a host wanted to uncover the MAC deal with of an IPv6 host addressed as 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/sixty four then the solicited Node Handle will look like the adhering to FF02::1:FF:CC:DDDD/104
When a sending hosts would like to get the MAC deal with from the IPv6 host of 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/sixty four it will consider the very last 24 bits of the known IPv6 address and location them into the remaining 24 bits of the Solicited Node Deal with and given that all IPv6 hosts hear to their personal Solicited Node addresses, when they hear their tackle they will reply with the MAC address.