There are a number of factors that make the IPv6 protocol suite interesting from a security standpoint. Firstly, being a new technology, technical personnel has much less confidence with the IPv6 protocols than with their IPv4 counterpart, and thus it is more likely that the security implications of the protocols be overlooked when the protocols are deployed.

Secondly, IPv6 implementations are much less mature than their IPv4 counterparts, and thus it is very likely that a number of vulnerabilities will be discovered in them before their robustness matches that of the existing IPv4 implementations.

Thirdly, security products such as firewalls and NIDS’s (Network Intrusion Detection Systems) usually have less support for the IPv6 protocols than for their IPv4 counterparts, either in terms of features or in terms of performance.

SOURCE: net-security.org

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