There are a growing number of large-scale IPv6 deployments occurring within enterprise, university, and government networks. For these networks to succeed, it is important that the IPv6 deployments are secure and the quality of service (QoS) must rival the existing IPv4 infrastructure. An important security aspect to consider is the local links (Layer 2). Traditional Layer 2 security differs between IPv4 and IPv6 because instead of using ARP—like IPv4—IPv6 moves the traditional Layer 2 operations to Layer 3 using various ICMP messages
IPv6 introduces a new set of technology link operations paradigms that differ significantly from IPv4. The changes include more end nodes that are permitted on the link (up to 2^64) and increased neighbor cache size on end nodes and the default router, which creates more opportunities for denial of service (DoS) attacks. There are also additional threats to consider in IPv6 including threats with the protocols in use, a couple of which are listed below:
- Neighbor Discovery Protocol (NDP) integrates all link operations that determine address assignment, router discovery, and associated tasks.
- Dynamic Host Configuration Protocol (DHCP) can have a lesser role in address assignment compared to IPv4.
Finally, non-centralized address assignment in IPv6 can create challenges for controlling address misuse by malicious hosts.
For more information on FHS concerns. read the new IPv6 FHS whitepaper.