+* RA_DOMAINS A space-separated list of DNS search domains from the RA
+* RA_HOPLIMIT Highest hop-limit received in RAs
+* RA_MTU MTU-value received in RA
+* RA_REACHABLE ND Reachability time
+* RA_RETRANSMIT ND Retransmit time
+* AFTR The DS-Lite AFTR domain name
+* MAPE / MAPT / LW4O6 Softwire rules for MAPE, MAPT and LW4O6