Cisco CCNA (200-301)Network FundamentalsMedium
An engineer captures traffic on an IPv6-enabled network and observes a packet destined for ff02::1. What is the purpose of this destination address?
- AIt is used to reach all IPv6-enabled nodes on the local link
- BIt routes traffic to the nearest server in a group of replicated servers
- CIt represents the loopback address for the local host
- DIt identifies a single specific host uniquely on the segment
Show answer & explanationAnswer & explanation
Correct answer: A. It is used to reach all IPv6-enabled nodes on the local link
The address ff02::1 is the reserved IPv6 multicast address for 'all-nodes' on the local link. Any packet sent to this address is received by every IPv6-enabled interface on that link, similar in purpose to a broadcast in IPv4 but scoped only to the local segment.
Why the other options are wrong
- B. This describes anycast addressing behavior, not multicast.
- C. The IPv6 loopback address is ::1, not ff02::1.
- D. A unique host address would be a unicast address, not a multicast address like ff02::1.
IPv6 Multicast (ff02::1)
ff02::1 is the reserved link-local scope multicast address representing all IPv6 nodes on a local network segment.
- ff02::1 = all-nodes multicast
- ff02::2 = all-routers multicast
- IPv6 has no broadcast; multicast replaces it
Memory trick: 'ff02::1 = everybody on the block gets the memo.'