Client                              Server
              ----------                          ----------
  1)  ----------------------- IKE Session ---------------------
      Length + Non-ESP Marker  ------->
      INFORMATIONAL
      HDR, SK {[N,] [D,]
             [CP,] ...}
                               <------- Length + Non-ESP Marker
                                                  INFORMATIONAL
                                             HDR, SK {[N,] [D,]
                                                     [CP], ...}
  2)  ---------------------  TLS Session  ---------------------
      close_notify             ------->
                               <-------            close_notify
  3)  --------------------  TCP Connection  -------------------
      TcpFin                   ------->
                               <-------                     Ack
                               <-------                  TcpFin
      Ack                      ------->
      --------------------  IKE SA Deleted  -------------------