Abstract. Networks are transitioning from IP version 4 to the new version 6. Fundamental differences in the protocols introduce new security challenges with varying levels of evidence. As enabling IPv6 in an existing network is often already challenging on the functional level, security aspects are overlooked, even those that are emphasized in literature. Reusing existing security solutions for IPv4 might seem easy and cost-effective, but is based on the unproven assumption that IPv6 attack traffic features the same characteristics. By performing network measurements and analyzing IPv6 attacks on the network-level, we determine the current state of security in the IPv6 domain. With the inevitable switch to the new protocol version, assessing the applicability of existing security approaches and determining the requirements for new solutions becomes a necessity.