# Neighbor Discovery Protocol (NDP)
![[Neighbor Discovery Protocol - Wikipedia#^pfeyvg]]
The main responsibility of NDP matches that of [[ARP]] in IPv4: it's to map IPv6 addresses to their link-layer MAC addresses.
It also facilitates [[IPv6]] [[SLAAC|Stateless Address Autoconfiguration (SLAAC)]], by allowing hosts to configure themselves without central management.
Here's a full list of NDP responsibilities:
![[Neighbor Discovery Protocol - Wikipedia#^6jrfsk]]
NDP achieves these through the use of the following ICMPv6 packets, meaning it's essential to allow ICMP to pass through the firewall of any network that uses [[SLAAC]].
![[Neighbor Discovery Protocol - Wikipedia#^5ba0d3]]