as ikev2-05-basic-psk This test enables --impair-minor-version-bump that will send a higher minor version number on the initiator. The connection should still establish fine. See: https://tools.ietf.org/html/rfc5996#section-2.5 The major version number should be incremented only if the packet formats or required actions have changed so dramatically that an older version node would not be able to interoperate with a newer version node if it simply ignored the fields it did not understand and took the actions specified in the older specification. The minor version number indicates new capabilities, and MUST be ignored by a node with a smaller minor version number, but used for informational purposes by the node with the larger minor version number. For example, it might indicate the ability to process a newly defined Notify message type. The node with the larger minor version number would simply note that its correspondent would not be able to understand that message and therefore would not send it.