Internet Assigned Numbers Authority Internet Control Message Protocol version 6 (ICMPv6) Parameters Last Updated 2023-11-07 Available Formats [IMG] XML [IMG] HTML [IMG] Plain text Registries included below • ICMPv6 "type" Numbers • ICMPv6 "Code" Fields • Type 0 - Reserved • Type 1 - Destination Unreachable • Type 2 - Packet Too Big • Type 3 - Time Exceeded • Type 4 - Parameter Problem • Type 128 - Echo Request • Type 129 - Echo Reply • Type 130 - Multicast Listener Query • Type 131 - Multicast Listener Report • Type 132 - Multicast Listener Done • Type 133 - Router Solicitation • Type 134 - Router Advertisement • Type 135 - Neighbor Solicitation • Type 136 - Neighbor Advertisement • Type 137 - Redirect Message • Type 138 - Router Renumbering • Type 139 - ICMP Node Information Query • Type 140 - ICMP Node Information Response • Type 141 - Inverse Neighbor Discovery • Type 142 - Inverse Neighbor Discovery • Type 144 - Home Agent Address Discovery • Type 145 - Home Agent Address Discovery • Type 146 - Mobile Prefix Solicitation • Type 147 - Mobile Prefix Advertisement • Type 157 - Duplicate Address Request Code Suffix • Type 158 - Duplicate Address Confirmation Code Suffix • Type 160 - Extended Echo Request • Type 161 - Extended Echo Reply • FMIPv6 Message Types (Value 154) • IPv6 Neighbor Discovery Option Formats • Trust Anchor option (Type 15) Name Type field • Certificate option (Type 16) Cert Type field • Option-Code for Handover Assist Information Option (Type 29) • Option-Code for Mobile Node Identifier Option (Type 30) • Qtypes • IPv6 ND Router Advertisement flags • Address Registration Option Status Values • 6LoWPAN Capability Bits • IPv6 Neighbor Discovery Prefix Information Option Flags • Address Registration Option Flags • Address Registration Option I-Field • PvD Option Flags • Crypto-Types ICMPv6 "type" Numbers Reference [RFC4443] Available Formats [IMG] CSV Range Registration Procedures 0-127 (Error messages) IETF Review 128-255 (Informational messages) IETF Review Type Name Reference 0 Reserved 1 Destination Unreachable [RFC4443] 2 Packet Too Big [RFC4443] 3 Time Exceeded [RFC4443] 4 Parameter Problem [RFC4443] 5-99 Unassigned 100 Private experimentation [RFC4443] 101 Private experimentation [RFC4443] 102-126 Unassigned 127 Reserved for expansion of ICMPv6 error messages [RFC4443] 128 Echo Request [RFC4443] 129 Echo Reply [RFC4443] 130 Multicast Listener Query [RFC2710] 131 Multicast Listener Report [RFC2710] 132 Multicast Listener Done [RFC2710] 133 Router Solicitation [RFC4861] 134 Router Advertisement [RFC4861] 135 Neighbor Solicitation [RFC4861] 136 Neighbor Advertisement [RFC4861] 137 Redirect Message [RFC4861] 138 Router Renumbering [RFC2894] 139 ICMP Node Information Query [RFC4620] 140 ICMP Node Information Response [RFC4620] 141 Inverse Neighbor Discovery Solicitation Message [RFC3122] 142 Inverse Neighbor Discovery Advertisement Message [RFC3122] 143 Version 2 Multicast Listener Report [RFC3810] 144 Home Agent Address Discovery Request Message [RFC6275] 145 Home Agent Address Discovery Reply Message [RFC6275] 146 Mobile Prefix Solicitation [RFC6275] 147 Mobile Prefix Advertisement [RFC6275] 148 Certification Path Solicitation Message [RFC3971] 149 Certification Path Advertisement Message [RFC3971] 150 ICMP messages utilized by experimental mobility protocols such as Seamoby [RFC4065] 151 Multicast Router Advertisement [RFC4286] 152 Multicast Router Solicitation [RFC4286] 153 Multicast Router Termination [RFC4286] 154 FMIPv6 Messages [RFC5568] 155 RPL Control Message [RFC6550] 156 ILNPv6 Locator Update Message [RFC6743] 157 Duplicate Address Request [RFC6775] 158 Duplicate Address Confirmation [RFC6775] 159 MPL Control Message [RFC7731] 160 Extended Echo Request [RFC8335] 161 Extended Echo Reply [RFC8335] 162-199 Unassigned 200 Private experimentation [RFC4443] 201 Private experimentation [RFC4443] 202-254 Unassigned 255 Reserved for expansion of ICMPv6 informational messages [RFC4443] ICMPv6 "Code" Fields Reference [RFC4443] Note Code field subregistries that are not explicitly documented by the specification defining the associated Type value are not individually listed here. Nevertheless, the meaning of Code field values depend upon the Type value [RFC 4443, Section 2.1]. Any specification wishing to define a previously unspecified Code subregistry for a given Type should note the procedures in [RFC 4443, Section 6.1]. Type 0 - Reserved Code No registrations at this time. Type 1 - Destination Unreachable Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code Name Reference 0 no route to destination 1 communication with destination administratively prohibited 2 beyond scope of source address [RFC4443] 3 address unreachable 4 port unreachable 5 source address failed ingress/egress policy [RFC4443] 6 reject route to destination [RFC4443] 7 Error in Source Routing Header [RFC6550][RFC6554] 8 Headers too long [RFC8883] Type 2 - Packet Too Big Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code 0 Type 3 - Time Exceeded Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code Name 0 hop limit exceeded in transit 1 fragment reassembly time exceeded Type 4 - Parameter Problem Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code Name Reference 0 erroneous header field encountered 1 unrecognized Next Header type encountered 2 unrecognized IPv6 option encountered 3 IPv6 First Fragment has incomplete IPv6 Header Chain [RFC7112] 4 SR Upper-layer Header Error [RFC8754] 5 Unrecognized Next Header type encountered by intermediate node [RFC8883] 6 Extension header too big [RFC8883] 7 Extension header chain too long [RFC8883] 8 Too many extension headers [RFC8883] 9 Too many options in extension header [RFC8883] 10 Option too big [RFC8883] Type 128 - Echo Request Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code 0 Type 129 - Echo Reply Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4443] Available Formats [IMG] CSV Code 0 Type 130 - Multicast Listener Query Registration Procedure(s) Standards Action or IESG Approval Reference [RFC2710] Available Formats [IMG] CSV Code 0 Type 131 - Multicast Listener Report Registration Procedure(s) Standards Action or IESG Approval Reference [RFC2710] Available Formats [IMG] CSV Code 0 Type 132 - Multicast Listener Done Registration Procedure(s) Standards Action or IESG Approval Reference [RFC2710] Available Formats [IMG] CSV Code 0 Type 133 - Router Solicitation Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4861] Available Formats [IMG] CSV Code 0 Type 134 - Router Advertisement Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4861] Available Formats [IMG] CSV Code 0 Type 135 - Neighbor Solicitation Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4861] Available Formats [IMG] CSV Code 0 Type 136 - Neighbor Advertisement Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4861] Available Formats [IMG] CSV Code 0 Type 137 - Redirect Message Registration Procedure(s) Standards Action or IESG Approval Reference [RFC4861] Available Formats [IMG] CSV Code 0 Type 138 - Router Renumbering Registration Procedure(s) IETF Review Reference [RFC2894] Available Formats [IMG] CSV Code Name 0 Router Renumbering Command 1 Router Renumbering Result 255 Sequence Number Reset Type 139 - ICMP Node Information Query Registration Procedure(s) Specification Required Expert(s) Unassigned Reference [RFC4620] Available Formats [IMG] CSV Code Name Reference 0 The Data field contains an IPv6 address which is the Subject of this Query. [RFC4620] 1 The Data field contains a name which is the Subject of this Query, or is empty, as in the case of a NOOP. [RFC4620] 2 The Data field contains an IPv4 address which is the Subject of this Query. [RFC4620] Type 140 - ICMP Node Information Response Registration Procedure(s) Specification Required Expert(s) Unassigned Reference [RFC4620] Available Formats [IMG] CSV Code Name Reference 0 A successful reply. The Reply Data field may or may not be empty. [RFC4620] 1 The Responder refuses to supply the answer. The Reply Data field will be empty. [RFC4620] 2 The Qtype of the Query is unknown to the Responder. The Reply Data field will be empty. [RFC4620] Type 141 - Inverse Neighbor Discovery Registration Procedure(s) Standards Action Reference [RFC3122] Available Formats [IMG] CSV Code 0 Type 142 - Inverse Neighbor Discovery Registration Procedure(s) Standards Action Reference [RFC3122] Available Formats [IMG] CSV Code 0 Type 144 - Home Agent Address Discovery Registration Procedure(s) IESG Approval Reference [RFC3775] Available Formats [IMG] CSV Code 0 Type 145 - Home Agent Address Discovery Registration Procedure(s) IESG Approval Reference [RFC3775] Available Formats [IMG] CSV Code 0 Type 146 - Mobile Prefix Solicitation Registration Procedure(s) IESG Approval Reference [RFC3775] Available Formats [IMG] CSV Code 0 Type 147 - Mobile Prefix Advertisement Registration Procedure(s) IESG Approval Reference [RFC3775] Available Formats [IMG] CSV Code 0 Type 157 - Duplicate Address Request Code Suffix Registration Procedure(s) IETF Review or IESG Approval Reference [RFC8505] Available Formats [IMG] CSV Code Suffix Meaning Reference 0 DAR message [RFC6775] 1 EDAR message with 64-bit ROVR field [RFC8505] 2 EDAR message with 128-bit ROVR field [RFC8505] 3 EDAR message with 192-bit ROVR field [RFC8505] 4 EDAR message with 256-bit ROVR field [RFC8505] 5-15 Unassigned Type 158 - Duplicate Address Confirmation Code Suffix Registration Procedure(s) IETF Review or IESG Approval Reference [RFC8505] Available Formats [IMG] CSV Code Suffix Meaning Reference 0 DAC message [RFC6775] 1 EDAC message with 64-bit ROVR field [RFC8505] 2 EDAC message with 128-bit ROVR field [RFC8505] 3 EDAC message with 192-bit ROVR field [RFC8505] 4 EDAC message with 256-bit ROVR field [RFC8505] 5-15 Unassigned Type 160 - Extended Echo Request Registration Procedure(s) First Come First Served Reference [RFC8335] Available Formats [IMG] CSV Code Name Reference 0 No Error [RFC8335] 1-255 Unassigned Type 161 - Extended Echo Reply Registration Procedure(s) First Come First Served Reference [RFC8335] Available Formats [IMG] CSV Code Name Reference 0 No Error [RFC8335] 1 Malformed Query [RFC8335] 2 No Such Interface [RFC8335] 3 No Such Table Entry [RFC8335] 4 Multiple Interfaces Satisfy Query [RFC8335] 5-255 Unassigned FMIPv6 Message Types (Value 154) Registration Procedure(s) RFC Required Reference [RFC5568] Available Formats [IMG] CSV Subtype Description Reference 0 Reserved [RFC5568] 1 Reserved [RFC5568] 2 RtSolPr [RFC5568] 3 PrRtAdv [RFC5568] 4 HI - Deprecated (Unavailable for Assignment) [RFC5568] 5 HAck - Deprecated (Unavailable for Assignment) [RFC5568] 6-255 Unassigned IPv6 Neighbor Discovery Option Formats Registration Procedure(s) RFC Required Reference [RFC4861] Note IETF working groups with working group consensus and area director approval can request reclaimable Neighbor Discovery option type assignments from IANA. See Section 13 of [RFC4861]. Available Formats [IMG] CSV Type Description Reference 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] 42-137 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] Trust Anchor option (Type 15) Name Type field Registration Procedure(s) Standards Action or IESG Approval Reference [RFC3971][RFC6495] Available Formats [IMG] CSV Value Description Reference 0 Reserved [RFC6495] 1 DER Encoded X.501 Name [RFC3971] 2 FQDN [RFC3971] 3 SHA-1 Subject Key Identifier (SKI) [RFC6495] 4 SHA-224 Subject Key Identifier (SKI) [RFC6495] 5 SHA-256 Subject Key Identifier (SKI) [RFC6495] 6 SHA-384 Subject Key Identifier (SKI) [RFC6495] 7 SHA-512 Subject Key Identifier (SKI) [RFC6495] 8-252 Unassigned 253-254 Reserved for Experimental Use [RFC6495] 255 Reserved [RFC6495] Certificate option (Type 16) Cert Type field Registration Procedure(s) Standards Action Reference [RFC3971] Available Formats [IMG] CSV Value Description Reference 0 Reserved 1 X.509v3 Certificate [RFC3971] 2-255 Unassigned Option-Code for Handover Assist Information Option (Type 29) Registration Procedure(s) Standards Action or IESG Approval Reference [RFC5271] Available Formats [IMG] CSV Value Description Reference 0 Reserved [RFC5271] 1 AN ID [RFC5271] 2 Sector ID [RFC5271] 3-255 Unassigned Option-Code for Mobile Node Identifier Option (Type 30) Registration Procedure(s) Standards Action or IESG Approval Reference [RFC5271] Available Formats [IMG] CSV Value Description Reference 0 Reserved [RFC5271] 1 NAI [RFC5271] 2 IMSI [RFC5271] 3-255 Unassigned Qtypes Registration Procedure(s) IETF Review Reference [RFC4620] Available Formats [IMG] CSV Value Description Reference 0 NOOP [RFC4620] 1 Unused [RFC4620] 2 Node Name [RFC4620] 3 Node Addresses [RFC4620] 4 IPv4 Addresses [RFC4620] 5-255 Unassigned IPv6 ND Router Advertisement flags Registration Procedure(s) Standards Action or IESG Approval Reference [RFC5175] Available Formats [IMG] CSV RA Option Bit Description Reference 0 M - Managed Address Configuration Flag [RFC4861] 1 O - Other Configuration Flag [RFC4861] 2 H - Mobile IPv6 Home Agent Flag [RFC3775] 3 Prf - Router Selection Preferences [RFC4191] 4 Prf - Router Selection Preferences [RFC4191] 5 P - Neighbor Discovery Proxy Flag [RFC4389] 6-53 R - Reserved; Available for assignment [RFC5175] 54-55 Private Experimentation [RFC5175] Address Registration Option Status Values Registration Procedure(s) Standards Action Reference [RFC6775][RFC9010] Available Formats [IMG] CSV Value Description Reference 0 Success [RFC6775] 1 Duplicate Address [RFC6775] 2 Neighbor Cache Full [RFC6775] 3 Moved [RFC8505] 4 Removed [RFC8505] 5 Validation Requested [RFC8505] 6 Duplicate Source Address [RFC8505] 7 Invalid Source Address [RFC8505] 8 Registered Address Topologically Incorrect [RFC8505] 9 6LBR Registry Saturated [RFC8505] 10 Validation Failed [RFC8505] 11-63 Unassigned [RFC9010] 6LoWPAN Capability Bits Registration Procedure(s) IETF Review or IESG Approval Reference [RFC7400] Available Formats [IMG] CSV Bit Description Reference 0-7 Reserved for Experimental Use [RFC7400] 8 Unassigned 9 AP-ND Enabled (1 bit) [RFC8928] 10 EDA Support (D bit) [RFC8505] 11 6LR capable (L bit) [RFC8505] 12 6LBR capable (B bit) [RFC8505] 13 Routing Registrar (P bit) [RFC8505] 14 EARO support (E bit) [RFC8505] 15 GHC capable bit (G bit) [RFC7400] 16-47 Unassigned IPv6 Neighbor Discovery Prefix Information Option Flags Registration Procedure(s) Standards Action Reference [RFC8425] Available Formats [IMG] CSV PIO Option Bit Description Reference 0 L - On-link Flag [RFC4861] 1 A - Autonomous Address Configuration Flag [RFC4861] 2 R - Router Address Flag [RFC6275] 3-7 Reserved Address Registration Option Flags Registration Procedure(s) IETF Review or IESG Approval Reference [RFC8505] Available Formats [IMG] CSV Bit Number Description Reference 0-5 Unassigned 6 R Flag [RFC8505] 7 T Flag [RFC8505] Address Registration Option I-Field Registration Procedure(s) IETF Review or IESG Approval Reference [RFC8505] Available Formats [IMG] CSV Value Meaning Reference 0 Abstract Index for Topology Selection [RFC8505] 1-3 Unassigned PvD Option Flags Registration Procedure(s) Standards Action Reference [RFC8801] Available Formats [IMG] CSV Bit Name Reference 0 H-flag [RFC8801] 1 L-flag [RFC8801] 2 R-flag [RFC8801] 3-11 Unassigned Crypto-Types Registration Procedure(s) Specification Required or IESG Approval Expert(s) Pascal Thubert, Mohit Sethi Reference [RFC8928] Available Formats [IMG] CSV Crypto-Type Elliptic Hash Signature Representation Conventions Public Key Size Signature Reference Value Curve Function Algorithm Size 0 NIST P-256 SHA-256 ECDSA Weierstrass, (un)compressed, MSB/msb-order, [SEC1] 33/65 bytes 64 bytes [RFC8928] [FIPS186-4] [RFC6234] [FIPS186-4] (compressed/uncompressed) 1 Curve25519 SHA-512 Ed25519 Edwards, compressed, LSB/lsb-order, [RFC8032] 32 bytes (compressed) 64 bytes [RFC8928] [RFC7748] [RFC6234] [RFC8032] 2 Curve25519 SHA-256 ECDSA Weierstrass, (un)compressed, MSB/msb-order, 33/65 bytes 64 bytes [RFC8928] [RFC7748] [RFC6234] [FIPS186-4] [draft-ietf-lwig-curve-representations-13] (compressed/uncompressed) 3-255 Footnote [1] It is only appropriate to use these values in explicitly configured experiments; they MUST NOT be shipped as defaults in implementations. See [RFC3692] for details. Licensing Terms