flow ah out proto udp from 1.1.1.1 port ntp to 2.2.2.2 peer 2.2.2.2 type require
flow ah in proto udp from 2.2.2.2 to 1.1.1.1 port ntp peer 2.2.2.2 type require
flow ah out proto udp from 1.1.1.1 port ntp to 2.2.2.2 peer 2.2.2.2 type require
flow ah in proto udp from 2.2.2.2 to 1.1.1.1 port ntp peer 2.2.2.2 type require