2013-05-17 As noted in , Multicast DNS can only carry DNS records with classes in the range 0-32767. Classes in the range 32768 to 65535 are incompatible with Multicast DNS. 0 0x0000 Standards Action 1-127 0x0000-0x007F IETF Review data CLASSes only 128-253 0x0080-0x00FD IETF Review QCLASSes and meta-CLASSes only 256-32767 0x0100-0x7FFF IETF Review 32768-57343 0x8000-0xDFFF Specification Required data CLASSes only 57344-65279 0xE000-0xFEFF Specification Required QCLASSes and meta-CLASSes only 65280-65534 0xFF00-0xFFFE Reserved for Private Use 65535 0xFFFF Standards Action 0 0x0000 Reserved 1 0x0001 Internet (IN) 2 0x0002 Unassigned 3 0x0003 Chaos (CH) D. Moon, "Chaosnet", A.I. Memo 628, Massachusetts Institute of Technology Artificial Intelligence Laboratory, June 1981. 4 0x0004 Hesiod (HS) Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical Plan - Name Service, April 1987. 5-253 0x0005-0x00FD Unassigned 254 0x00FE QCLASS NONE 255 0x00FF QCLASS * (ANY) 256-65279 0x0100-0xFEFF Unassigned 65280-65534 0xFF00-0xFFFE Reserved for Private Use 65535 0xFFFF Reserved 0 0x0000 RRTYPE zero is used as a special indicator for the SIG RR , and in other circumstances and must never be allocated for ordinary use. 1-127 0x0000-0x007F DNS RRTYPE Allocation Policy data TYPEs 128-255 0x0080-0x00FF DNS RRTYPE Allocation Policy Q TYPEs, Meta TYPEs 256-61439 0x0100-0xEFFF DNS RRTYPE Allocation Policy data RRTYPEs 61440-65279 0xF000-0xFEFF IETF Review 65280-65534 0xFF00-0xFFFE Reserved for Private Use 65535 0xFFFF Reserved (Standards Action) A 1 a host address NS 2 an authoritative name server MD 3 a mail destination (OBSOLETE - use MX) MF 4 a mail forwarder (OBSOLETE - use MX) CNAME 5 the canonical name for an alias SOA 6 marks the start of a zone of authority MB 7 a mailbox domain name (EXPERIMENTAL) MG 8 a mail group member (EXPERIMENTAL) MR 9 a mail rename domain name (EXPERIMENTAL) NULL 10 a null RR (EXPERIMENTAL) WKS 11 a well known service description PTR 12 a domain name pointer HINFO 13 host information MINFO 14 mailbox or mail list information MX 15 mail exchange TXT 16 text strings RP 17 for Responsible Person AFSDB 18 for AFS Data Base location X25 19 for X.25 PSDN address ISDN 20 for ISDN address RT 21 for Route Through NSAP 22 for NSAP address, NSAP style A record NSAP-PTR 23 for domain name pointer, NSAP style SIG 24 for security signature KEY 25 for security key PX 26 X.400 mail mapping information GPOS 27 Geographical Position AAAA 28 IP6 Address LOC 29 Location Information NXT 30 Next Domain (OBSOLETE) EID 31 Endpoint Identifier NIMLOC 32 Nimrod Locator SRV 33 Server Selection ATMA 34 ATM Address ATM Forum Technical Committee, "ATM Name System, V2.0", Doc ID: AF-DANS-0152.000, July 2000. Available from and held in escrow by IANA. NAPTR 35 Naming Authority Pointer KX 36 Key Exchanger CERT 37 CERT A6 38 A6 (OBSOLETE - use AAAA) DNAME 39 DNAME SINK 40 SINK OPT 41 OPT APL 42 APL DS 43 Delegation Signer SSHFP 44 SSH Key Fingerprint IPSECKEY 45 IPSECKEY RRSIG 46 RRSIG NSEC 47 NSEC DNSKEY 48 DNSKEY DHCID 49 DHCID NSEC3 50 NSEC3 NSEC3PARAM 51 NSEC3PARAM TLSA 52 TLSA Unassigned 53-54 HIP 55 Host Identity Protocol NINFO 56 NINFO NINFO/ninfo-completed-template RKEY 57 RKEY RKEY/rkey-completed-template TALINK 58 Trust Anchor LINK TALINK/talink-completed-template CDS 59 Child DS CDS/cds-completed-template Unassigned 60-98 SPF 99 UINFO 100 IANA-Reserved UID 101 IANA-Reserved GID 102 IANA-Reserved UNSPEC 103 IANA-Reserved NID 104 ILNP/nid-completed-template L32 105 ILNP/l32-completed-template L64 106 ILNP/l64-completed-template LP 107 ILNP/lp-completed-template EUI48 108 EUI48/eui48-completed-template EUI64 109 EUI64/eui64-completed-template Unassigned 110-248 TKEY 249 Transaction Key TSIG 250 Transaction Signature IXFR 251 incremental transfer AXFR 252 transfer of an entire zone MAILB 253 mailbox-related RRs (MB, MG or MR) MAILA 254 mail agent RRs (OBSOLETE - see MX) * 255 A request for all records the server/cache has available URI 256 URI URI/uri-completed-template CAA 257 Certification Authority Restriction CAA/caa-completed-template Unassigned 258-32767 TA 32768 DNSSEC Trust Authorities Deploying DNSSEC Without a Signed Root. Technical Report 1999-19, Information Networking Institute, Carnegie Mellon University, April 2004. DLV 32769 DNSSEC Lookaside Validation Unassigned 32770-65279 Private use 65280-65534 Reserved 65535 In , two types are defined. It is not clear that these are in use, though if so their assignment does conflict with those above. NB 32 NetBIOS general Name Service NBSTAT 33 NetBIOS NODE STATUS Standards Action as modified by 0 Query 1 IQuery (Inverse Query, OBSOLETE) 2 Status 3 Unassigned 4 Notify 5 Update 6-15 Unassigned IETF Review 0 NoError No Error 1 FormErr Format Error 2 ServFail Server Failure 3 NXDomain Non-Existent Domain 4 NotImp Not Implemented 5 Refused Query Refused 6 YXDomain Name Exists when it should not 7 YXRRSet RR Set Exists when it should not 8 NXRRSet RR Set that should exist does not 9 NotAuth Server Not Authoritative for zone 9 NotAuth Not Authorized 10 NotZone Name not contained in zone 11-15 Unassigned 16 BADVERS Bad OPT Version 16 BADSIG TSIG Signature Failure 17 BADKEY Key not recognized 18 BADTIME Signature out of time window 19 BADMODE Bad TKEY Mode 20 BADNAME Duplicate key name 21 BADALG Algorithm not supported 22 BADTRUNC Bad Truncation 23-3840 Unassigned 3841-4095 Reserved for Private Use 4096-65534 Unassigned 65535 Reserved, can be allocated by Standards Action Registry closed per 0 0x0000 Reserved; registry closed 1 0x0001 Andrews File Service v3.0 Location Service 2 0x0002 DCE/NCA root cell directory node 3-65279 0x0003-0xFEFF Not allocated; registry closed 65280-65534 0xFF00-0xFFFE Reserved for Private Use 65535 0xFFFF Reserved; registry closed Standards Action Olafur Gudmundsson Registration rules to be as follows: New DHCID RR type codes are tentatively assigned after the specification for the associated type code, published as an Internet Draft, has received expert review by a designated expert. The final assignment of DHCID RR type codes is through Standards Action, as defined in . 0x0000 The 1-octet 'htype' followed by 'hlen' octets of 'chaddr' from a DHCPv4 client's DHCPREQUEST. 0x0001 The data octets (i.e., the Type and Client-Identifier fields) from a DHCPv4 client's Client Identifier option. 0x0002 The client's DUID (i.e., the data octets of a DHCPv6 client's Client Identifier option or the DUID field from a DHCPv4 client's Client Identifier option). 0x0003-0xFFFE Unassigned 0xFFFF Reserved Standards Action The top 2 bits of the first byte of an DNS label indicate the type of label. 0 0 Normal label lower 6 bits is the length of the label Standard 1 1 Compressed label the lower 6 bits and the 8 bits from next octet form a pointer to the compression target. Standard 0 1 Extended label type the lower 6 bits of this type (section 3) indicate the type of label in use Proposed 0 1 0 0 0 0 0 1 Binary Label Historic 0 1 1 1 1 1 1 1 Reserved for future expansion. Proposed 1 0 Unallocated Expert Review Olafur Gudmundsson 0 Reserved 1 LLQ On-hold 2 UL On-hold 3 NSID Standard 4 Reserved 5 DAU Standard 6 DHU Standard 7 N3U Standard 8-65000 Unassigned 65001-65534 Reserved for Local/Experimental Use 65535 Reserved for future expansion Standards Action In DNS query header there is a flag field in the second 16 bit word in query from bit 5 through bit 11 ( section 4.1.1) bit 5 AA Authoritative Answer bit 6 TC Truncated Response bit 7 RD Recursion Desired bit 8 RA Recursion Allowed bit 9 Reserved bit 10 AD Authentic Data bit 11 CD Checking Disabled Standards Action Bit 0 DO DNSSEC answer OK Bit 1-15 Reserved Standards Action 0 EDNS version 0 1-255 Unassigned Donald E. Eastlake, III mailto:d3e3e3&gmail.com 1997-11 George Barwood mailto:george.barwood&blueyonder.co.uk 2011-06-06 Jim Reid mailto:jim&telnic.org 2008-01-21 Michael Patton mailto:map&bbn.com 1995-06 Patrik Faltstrom mailto:paf&cisco.com 2011-02-22 Phillip Hallam-Baker mailto:phill&hallambaker.com 2011-04-07 Sam Weiler mailto:weiler+iana&tislabs.com 2005-12 Wouter Wijngaards mailto:wouter&nlnetlabs.nl 2010-02-17