NDP Message Sorter — TechKnowSurge

About this interactive

IPv6 has no ARP and no broadcast, so Neighbor Discovery does those jobs with five ICMPv6 messages. A solicitation is a question and an advertisement is its answer. A host sends a router solicitation (type 133) to the all-routers group to ask which routers are on its link; routers answer with a router advertisement (type 134), carrying the prefix and prefix length a host needs for SLAAC, and they also send advertisements now and then without being asked. A host that needs a neighbor's MAC address sends a neighbor solicitation (type 135) to that neighbor's solicited-node group, and the neighbor answers with a neighbor advertisement (type 136). Duplicate address detection reuses the neighbor solicitation, sent from the unspecified address, ::. The fifth, the redirect (type 137), is a router's way of saying that another router on the same link is a better first hop for a particular destination. Ten of the twenty-three cards are drawn each run, and after you check, every card says which message it is and why.

What you'll learn

Name the Neighbor Discovery message a host or router sends in a given situation: router solicitation, router advertisement, neighbor solicitation, neighbor advertisement or redirect
Match each NDP message to its ICMPv6 type number, 133 to 137

Aligned to

Cisco CCNA

1.9 Describe IPv6 address types

CompTIA Network+

3.4 Given a scenario, implement IPv4 and IPv6 network services

Key terms

Neighbor Discovery Protocol: An IPv6 protocol that replaces ARP and handles router discovery, address autoconfiguration, and address resolution on local links.
Router Solicitation: An ICMPv6 message sent by an IPv6 host when it initializes to prompt routers on the link to send a Router Advertisement immediately, rather than waiting for the next periodic RA interval. Router Solicitation speeds up IPv6 address autoconfiguration on newly connected devices.
Neighbor Solicitation: An ICMPv6 message used in IPv6 Neighbor Discovery to request the MAC address corresponding to a specific IPv6 address or to verify that a neighbor is still reachable. Neighbor Solicitation is also used during Duplicate Address Detection to check that a new IPv6 address is unique.
Neighbor Advertisement: An ICMPv6 message sent in response to a Neighbor Solicitation, providing the MAC address corresponding to a requested IPv6 address as part of the Neighbor Discovery Protocol. NA messages are also sent unsolicited to announce link-layer address changes.
Redirect: An ICMPv6 Type 137 message sent by a router to inform a host of a better route to a destination when an alternate path is available.
Duplicate Address Detection: An IPv6 mechanism that verifies a newly assigned address is unique on the link before it is used for communication. A device sends a Neighbor Solicitation for its tentative address; if no response is received, the address is confirmed unique and assigned.

Topics

Ipv6 Ndp Icmpv6 Neighbor Discovery Interactive Categorize

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