Copyright (C) Internet Systems Consortium, Inc. ("ISC")

See COPYRIGHT in the source root or https://isc.org/copyright.html for terms.

BIND 9 is striving for strict compliance with IETF standards.  We
believe this release of BIND 9 complies with the following RFCs, with
the caveats and exceptions listed in the numbered notes below.  Note
that a number of these RFCs do not have the status of Internet
standards but are proposed or draft standards, experimental RFCs,
or Best Current Practice (BCP) documents.  The list is non exhaustive.

  RFC1034
  RFC1035 [1] [2]
  RFC1101
  RFC1123
  RFC1183
  RFC1521 [17]
  RFC1535
  RFC1536
  RFC1706
  RFC1712
  RFC1750
  RFC1876
  RFC1982
  RFC1995
  RFC1996
  RFC2136
  RFC2163
  RFC2181
  RFC2230
  RFC2308
  RFC2539
  RFC2606 [18]
  RFC2782
  RFC2845
  RFC2874 [18]
  RFC2915
  RFC2930
  RFC2931 [5]
  RFC3007
  RFC3110
  RFC3123
  RFC3225
  RFC3226
  RFC3363 [6]
  RFC3490 [7]
  RFC3491 (Obsoleted by 5890, 5891) [7]
  RFC3493
  RFC3496
  RFC3597
  RFC3645
  RFC4025
  RFC4033 [19]
  RFC4034
  RFC4035
  RFC4074
  RFC4255
  RFC4294 - Section 5.1 [8]
  RFC4343
  RFC4398
  RFC4408
  RFC4431
  RFC4470 [9]
  RFC4509
  RFC4592
  RFC4635
  RFC4701
  RFC4892
  RFC4955 [10]
  RFC5001
  RFC5011
  RFC5155
  RFC5205
  RFC5452 [11]
  RFC5702
  RFC5933 [12]
  RFC5936
  RFC5952
  RFC5966
  RFC6052
  RFC6147 [13]
  RFC6303
  RFC6604
  RFC6605 [14]
  RFC6672
  RFC6698
  RFC6742
  RFC6725
  RFC6840 [15]
  RFC6844
  RFC6891
  RFC6944
  RFC7043
  RFC7314
  RFC7344 [20]
  RFC7477
  RFC7553
  RFC7793
  RFC7830 [16]
  RFC7929
  RFC8080

The following DNS related RFC have been obsoleted

  RFC2535 (Obsoleted by 4034, 4035) [3] [4]
  RFC2537 (Obsoleted by 3110)
  RFC2538 (Obsoleted by 4398)
  RFC2671 (Obsoleted by 6891)
  RFC2672 (Obsoleted by 6672)
  RFC2673 (Obsoleted by 6891)
  RFC3008 (Obsoleted by 4034, 4035)
  RFC3152 (Obsoleted by 3596)
  RFC3445 (Obsoleted by 4034, 4035)
  RFC3655 (Obsoleted by 4034, 4035)
  RFC3658 (Obsoleted by 4034, 4035)
  RFC3755 (Obsoleted by 4034, 4035)
  RFC3757 (Obsoleted by 4034, 4035)
  RFC3845 (Obsoleted by 4034, 4035)

[1] Queries to zones that have failed to load return SERVFAIL rather
than a non-authoritative response.  This is considered a feature.

[2] CLASS ANY queries are not supported.  This is considered a
feature.

[3] Wildcard records are not supported in DNSSEC secure zones.

[4] Servers authoritative for secure zones being resolved by BIND
9 must support EDNS0 (RFC2671), and must return all relevant SIGs
and NXTs in responses rather than relying on the resolving server
to perform separate queries for missing SIGs and NXTs.

[5] When receiving a query signed with a SIG(0), the server will
only be able to verify the signature if it has the key in its local
authoritative data; it will not do recursion or validation to
retrieve unknown keys.

[6] Section 4 is ignored.

[7] Requires --with-idn to enable entry of IDN labels within dig,
host and nslookup at compile time.  ACE labels are supported
everywhere with or without --with-idn.

[8] Section 5.1 - DNAME records are fully supported.

[9] Minimally Covering NSEC Record are accepted but not generated.

[10] Will interoperate with correctly designed experiments.

[11] Named only uses ports to extend the id space, address are not
used.

[12] Conditional on the OpenSSL library being linked against
supporting GOST.

[13] Section 5.5 does not match reality.  Named uses the presence
of DO=1 to detect if validation may be occurring.  CD has no bearing
on whether validation is occurring or not.

[14] Conditional on the OpenSSL library being linked against
supporting ECDSA.

[15] Section 5.9 - Always set CD=1 on queries.  This is *not* done as
it prevents DNSSEC working correctly through another recursive server.

When talking to a recurive server the best algorithm to do is send
CD=0 and then send CD=1 iff SERVFAIL is returned in case the recurive
server has a bad clock and/or bad trust anchor.  Alternatively one
can send CD=1 then CD=0 on validation failure in case the recursive
server is under attack or there is stale / bogus authoritative data.

[16] Named doesn't currently encrypt DNS requests so the PAD option
is accepted but not returned in responses.

[17] Only the Base 64 encoding specification.

[18] Not applicable to DNS server implementations.

[19] Loading and serving of A6 records only.  A6 records were moved
/o the experimental category by RFC3363.

[20] Updating of parent zones is not yet implemented.
