CCNA--CCNP-Instruction--IPv6-Addressing

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

In the course of your occupation as a Cisco community engineer you will have to offer comprehension IPv6 tackle structure.

For your CCNA and CCNP studies you have to at some stage confront and comprehend IPv6. At 1st look it can see quite overwhelming in comparison to IPv4 that we are all employed to, in true truth IPv6 is fairly a merely addressing protocol after you get past the initial shock. In this post we are going to have a seem at Neighbour discovery protocol for layer two mapping.

When an IPv6 host or router requirements to send out a packet to some other host on the same network it will first of all seem into it's very own neighborhood neighbour database 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 require to resolve the acknowledged layer 3 IPv6 tackle to a currently unfamiliar Layer 2 MAC tackle and to do this the host uses the Neighbor Discovery Protocol or NDP to find out the MAC handle dynamically.



ccnp training Sending host will use a multicast information called a Neighbor Solicitation (NS) icmp information to question the acquiring host for it really is MAC handle, the getting host will reply with a Neighbor Advertisement (NA) icmp message unicast in return with the requested MAC address.

How IPv6 achieves this is all in the design of the Neighbor Solicitation message which makes use of a special IPv6 destination deal with known as a "Solicited Node Multicast", this solicited Node Multicast at any offered minute represented all of the IPv6 hosts on the hyperlink, the very last 24 bits of the Solicited Node Handle are the final 24 bits of the IPv6 tackle of the system that a host is requesting the MAC from.

The IPv6 multicast spot tackle is FF02::1:FF:/104 the ultimate 24 bits are manufactured up of the very last 24 bits of the IPv6 deal with to which the message is becoming despatched to. For illustration if a host wished to discover the MAC deal with of an IPv6 host dealt with as 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/64 then the solicited Node Handle will seem like the adhering to FF02::1:FF:CC:DDDD/104

When a sending hosts would like to get the MAC address from the IPv6 host of 2222:3333:4444:5555:6666:AAAA:BBBB:CCCC:DDDD/sixty four it will take the previous 24 bits of the recognized IPv6 tackle and location them into the remaining 24 bits of the Solicited Node Handle and since all IPv6 hosts pay attention to their possess Solicited Node addresses, when they hear their address they will reply with the MAC address.