1 Source Link-layer Address [RFC4861] 2 Target Link-layer Address [RFC4861] 3 Prefix Information [RFC4861] 4 Redirected Header [RFC4861] 5 MTU [RFC4861] 6 NBMA Shortcut Limit Option [RFC2491] 7 Advertisement Interval Option [RFC6275] 8 Home Agent Information Option [RFC6275] 9 Source Address List [RFC3122] 10 Target Address List [RFC3122] 11 CGA option [RFC3971] 12 RSA Signature option [RFC3971] 13 Timestamp option [RFC3971] 14 Nonce option [RFC3971] 15 Trust Anchor option [RFC3971] 16 Certificate option [RFC3971] 17 IP Address/Prefix Option [RFC5568] 18 New Router Prefix Information Option [RFC4068] 19 Link-layer Address Option [RFC5568] 20 Neighbor Advertisement Acknowledgment Option [RFC5568] 21 PvD ID Router Advertisement Option [RFC8801] 22 Unassigned 23 MAP Option [RFC4140] 24 Route Information Option [RFC4191] 25 Recursive DNS Server Option [RFC5006][RFC8106] 26 RA Flags Extension Option [RFC5175] 27 Handover Key Request Option [RFC5269] 28 Handover Key Reply Option [RFC5269] 29 Handover Assist Information Option [RFC5271] 30 Mobile Node Identifier Option [RFC5271] 31 DNS Search List Option [RFC8106] 32 Proxy Signature (PS) [RFC6496] 33 Address Registration Option [RFC6775] 34 6LoWPAN Context Option [RFC6775] 35 Authoritative Border Router Option [RFC6775] 36 6LoWPAN Capability Indication Option (6CIO) [RFC7400] 37 DHCP Captive-Portal [RFC8910] 38 PREF64 option [RFC8781] 39 Crypto-ID Parameters Option (CIPO) [RFC8928] 40 NDP Signature Option (NDPSO) [RFC8928] 41 Resource Directory Address Option [RFC9176] 42 Consistent Uptime Option [RFC9685] 43-137 Unassigned 138 CARD Request option [RFC4065] 139 CARD Reply option [RFC4065] 140-143 Unassigned 144 Encrypted DNS Option [RFC9463] 145-252 Unassigned 253 RFC3692-style Experiment 1 [1] [RFC4727] 254 RFC3692-style Experiment 2 [1] [RFC4727]