< draft-ietf-dnsop-dnssec-trust-anchor-03.txt   draft-ietf-dnsop-dnssec-trust-anchor-04.txt >
Intended Status: Informational M. Larson Intended Status: Informational M. Larson
DNS Operations VeriSign DNS Operations VeriSign
Internet-Draft O. Gudmundsson Internet-Draft O. Gudmundsson
Expires: September 10, 2009 OGUD Consulting LLC Expires: April 26, 2011 Shinkuro Inc.
March 9, 2009 October 23, 2010
DNSSEC Trust Anchor Configuration and Maintenance DNSSEC Trust Anchor Configuration and Maintenance
draft-ietf-dnsop-dnssec-trust-anchor-03 draft-ietf-dnsop-dnssec-trust-anchor-04
Abstract
This document recommends a preferred format for specifying trust
anchors in DNSSEC validating security-aware resolvers and describes
how such a resolver should initialize trust anchors for use. This
document also describes different mechanisms for keeping trust
anchors up to date over time.
Status of this Memo Status of this Memo
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Copyright Notice Copyright Notice
Copyright (c) 2009 IETF Trust and the persons identified as the Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Abstract include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
This document recommends a preferred format for specifying trust described in the Simplified BSD License.
anchors in DNSSEC validating security-aware resolvers and describes
how such a resolver should initialize trust anchors for use. This
document also describes different mechanisms for keeping trust
anchors up to date over time.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Trust Anchor Format . . . . . . . . . . . . . . . . . . . . . 5 2. Trust Anchor Format and Storage . . . . . . . . . . . . . . . 4
2.1. Trust Anchor Storage . . . . . . . . . . . . . . . . . . . 4
3. Trust Anchor Priming . . . . . . . . . . . . . . . . . . . . . 6 3. Trust Anchor Priming . . . . . . . . . . . . . . . . . . . . . 6
4. Trust Anchor Maintenance . . . . . . . . . . . . . . . . . . . 8 4. Trust Anchor Maintenance . . . . . . . . . . . . . . . . . . . 8
5. Security considerations . . . . . . . . . . . . . . . . . . . 10 5. Security considerations . . . . . . . . . . . . . . . . . . . 10
6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 11 6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 11
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12
8. Normative References . . . . . . . . . . . . . . . . . . . . . 13 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.1. Normative References . . . . . . . . . . . . . . . . . . . 13
8.2. Informative References . . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction 1. Introduction
The DNSSEC standards documents ([RFC4033], [RFC4034] and [RFC4035]) The DNSSEC standards documents ([RFC4033], [RFC4034] and [RFC4035])
describe the need for trust anchors and how they are used. A describe the need for trust anchors and how they are used. A
validating security-aware resolver (subsequently referred to as a validating security-aware resolver (subsequently referred to as a
"validating resolver") needs to be configured with one or more trust "validating resolver") needs to be configured with one or more trust
anchors, which specify the public keys of signed zones. To anchors, which specify the public keys of signed zones. To
authenticate DNS data, a validating resolver builds a chain of trust authenticate DNS data, a validating resolver builds a chain of trust
from a configured trust anchor to that data. from a configured trust anchor to that data.
In a widespread public DNSSEC deployment, the DNS root zone would be The DNS root zone is signed and a validating resolver needs to be
signed and a validating resolver would need to be configured with at configured with at least the root zone's trust anchor. A validating
least the root zone's trust anchor. A validating resolver might need resolver might need additional trust anchors configured to
additional trust anchors configured to accommodate islands of accommodate islands of security. (An island of security is a signed,
security. (An island of security is a signed, delegated zone that delegated zone that does not have an authentication chain from its
does not have an authentication chain from its delegating parent.) delegating parent.) Consider the situation now that the root zone is
For example, consider the situation where the root zone is signed but signed but when a given top-level domain (TLD) zone is not signed.
a given top-level domain (TLD) zone is not. Various second-level Various second-level zones under this unsigned TLD might be signed
zones under this unsigned TLD might be signed and resolver operators and resolver operators might want to validate responses from those
might want to validate responses from those zones, requiring a zones, requiring a validating resolver to be configured with those
validating resolver to be configured with those zones' trust anchors. zones' trust anchors. Note islands of security can appear at any
depth in the DNS tree.
Because many validating resolvers would be configured with trust Because many different validating resolvers need be configured there
anchors in a widespread DNSSEC deployment, there is a benefit to is a benefit to creating a common trust anchor format. A similar
creating a common trust anchor format. A similar situation has situation has occurred with the "root hints", the list of root name
occurred with the "root hints", the list of root name server names server names and IP addresses: this information is distributed in
and IP addresses: this information is distributed in standard master standard master file format and many resolver implementations support
file format and many resolver implementations support this common this common format.
format.
To simplify this trust anchor configuration process that will occur To simplify this trust anchor configuration process that will occur
on a large number of resolvers, this document offers guidance to on a large number of resolvers, this document offers guidance to
validating resolver implementers by specifying a standardized format validating resolver implementers by specifying a standardized format
for describing trust anchors. The document also describes how a for describing trust anchors. The document also describes how a
validating resolver should initialize or "prime" trust anchors before validating resolver should initialize or "prime" trust anchors before
first use. Finally, the document lists options for keeping trust first use. Finally, the document lists options for keeping trust
anchor information current over time. anchor information current over time.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
2. Trust Anchor Format 2. Trust Anchor Format and Storage
A trust anchor is a DNSSEC public key configured in a validating A trust anchor is a DNSSEC public key configured in a validating
resolver. A validating resolver's configuration MUST allow one or resolver. A validating resolver's configuration MUST allow one or
more trust anchors to be specified. According to the definition in more trust anchors to be specified. According to the definition in
Section 2 of RFC 4033 [RFC4033], a trust anchor can be specified as Section 2 of RFC 4033 [RFC4033], a trust anchor can be specified as
either a public key from a DNSKEY resource record (RR) or the hash of either a public key from a DNSKEY resource record (RR) or the hash of
a public key as found in a DS RR. (DS records are defined in Section a public key as found in a DS RR. (DS records are defined in Section
5 of RFC 4034 [RFC4034].) 5 of RFC 4034 [RFC4034].)
This document RECOMMENDS that a trust anchor be specified using the This document RECOMMENDS that a trust anchor be specified using the
skipping to change at page 5, line 27 skipping to change at page 4, line 27
from a DS record rather than from a DNSKEY record. A trust anchor from a DS record rather than from a DNSKEY record. A trust anchor
specified in this manner will use all the fields from the specified in this manner will use all the fields from the
corresponding key's DS record, including the owner name to indicate corresponding key's DS record, including the owner name to indicate
which zone the trust anchor corresponds to as well as the various which zone the trust anchor corresponds to as well as the various
fields from the DS RDATA. The digest algorithm SHOULD be SHA-256 fields from the DS RDATA. The digest algorithm SHOULD be SHA-256
[RFC4509], which is DS digest type 2. DS records using SHA-1 (DS [RFC4509], which is DS digest type 2. DS records using SHA-1 (DS
digest type 1) to specify trust anchors are NOT RECOMMENDED: RFC 4509 digest type 1) to specify trust anchors are NOT RECOMMENDED: RFC 4509
encourages the use of DS RRs using SHA-256 over those using SHA-1. encourages the use of DS RRs using SHA-256 over those using SHA-1.
Specifying a trust anchor using a DS format instead of a DNSKEY Specifying a trust anchor using a DS format instead of a DNSKEY
format offers a slight advantage because it forces the resolver to format offers an advantage because it forces the resolver to make a
make a DNS query to obtain the trust anchor's complete DNSKEY RRSet DNS query to obtain the trust anchor's complete DNSKEY RRSet during a
during a priming operation (described below). If only a DNSKEY priming operation (described below). If only a DNSKEY record were
record were specified, resolver implementers could conceivably avoid specified, resolver implementers could conceivably avoid priming the
priming the trust anchor. But priming is desirable because it causes trust anchor. But priming is desirable because it causes the
the resolver to retrieve an up-to-date version of a zone's DNSKEY resolver to retrieve an up-to-date version of a zone's DNSKEY RRSet
RRSet from one of the zone's authoritative servers. It should be from one of the zone's authoritative servers. It should be noted
noted that in practice, priming is almost always required because that in practice, priming is frequently required, when the data in
data in the trust anchor zone will usually be signed with a different the trust anchor zone is signed with a different key than the one
key than the one configured as the trust anchor, thus requiring the configured as the trust anchor.
validating resolver to obtain all keys in the DNSKEY RRSet.
Using a DS format is also recommended because it is smaller than the Using a DS format is also recommended because it is smaller than the
DNSKEY format and is easier to enter manually, either by typing or DNSKEY format and is easier to compare manually, either by typing or
cutting and pasting. cutting and pasting.
2.1. Trust Anchor Storage
For trust anchors to be useful the validating resolver needs to be
able to read a file with the trust anchors. This document recommends
that all resolvers be able to read trust anchors specified in a file
in the following format:
ZoneName [DS] KeyTag DNSKEY-Algorithm Digest-type Digest
Any truncated digest SHOULD be ignored. The text "DS" in input is
optional. The input format assumes that the trust anchor is either
in the IN class or is valid in all classes.
Validating resolvers ought to be able write out a list of current
trust anchors in the format above. Validating resolvers that perform
trust anchor maintenance MUST be able to update their trust anchor
storage.
Example: (ID width rules force text onto two lines)
. 19036 8 2
49AAC11D7B6F6446702E54A1607371607A1A41855200FD2CE1CDDE32F24E8FB5
Note: Trust anchor maintenance [RFC5011] and other schemas may
require a different format as timers and other meta data is needed.
3. Trust Anchor Priming 3. Trust Anchor Priming
A validating resolver needs to obtain and validate the DNSKEY RRSet A validating resolver needs to obtain and validate the DNSKEY RRSet
corresponding to a configured DS for that trust anchor to be usable corresponding to a configured DS for that trust anchor to be usable
in DNSSEC validation. This process is called "priming" the trust in DNSSEC validation. This process is called "priming" the trust
anchor. Priming can occur when the validating resolver starts, but a anchor. Priming can occur when the validating resolver starts, but a
validating resolver SHOULD defer priming of individual trust anchors validating resolver may want to defer priming of individual trust
until each is first needed for verification. This priming on demand anchors until each is first needed for verification. This priming on
is especially important when a validating resolver is configured with demand is especially important when a validating resolver is
a large number of trust anchors to avoid sending a large number of configured with a large number of trust anchors to avoid sending a
DNS queries on start-up. This section adds additional details to the large number of DNS queries on startup. This section adds additional
discussion of trust anchors in Section 5 of RFC 4035 [RFC4035]. details to the discussion of trust anchors in Section 5 of RFC 4035
[RFC4035].
Following are the steps a validating resolver SHOULD take to prime a Following are the steps a validating resolver SHOULD take to prime a
configured trust anchor: configured trust anchor:
1. Read the trust anchor's information (corresponding to the fields 1. Read the trust anchor's information (corresponding to the fields
in a DS record) from the validating resolver's configuration in a DS record as descried above) from the validating resolver's
(e.g., a text file). configuration (e.g., a text file).
2. Look up the DNSKEY RRSet corresponding to the owner name of the 2. Look up the DNSKEY RRSet corresponding to the owner name of the
trust anchor. (The validating resolver can either perform trust anchor. (The validating resolver can either perform
iterative resolution or request recursive service from a iterative resolution or request recursive service from a
recursive name server, depending on its capabilities.) recursive name server, depending on its capabilities.)
3. Verify that the DNSKEY RR corresponding to the configured trust 3. Verify that one of the DNSKEY RR(s) correspond to one the
anchor (i.e., the DNSKEY whose hash is configured) appears in the configured trust anchor(s) (i.e., one of the DNSKEY whose hash is
DNSKEY RRSet and that this DNSKEY RR has the Zone Key Flag configured) appears in the DNSKEY RRSet and that this DNSKEY RR
(DNSKEY RDATA bit 7) set. (This bit only indicates that the has the Zone Key Flag (DNSKEY RDATA bit 7) set. (This bit only
DNSKEY is allowed to sign the zone. This DNSKEY may or not be a indicates that the DNSKEY is allowed to sign the zone data. This
zone signing key.) DNSKEY may or may not be a zone signing key (ZSK) as defined in
RFC 4641 [RFC4641].)
4. Verify that the DNSKEY RRSet is signed by one of the DNSKEYs 4. Verify that the DNSKEY RRSet is signed by one of the DNSKEYs
found in the previous step, i.e., that there exists a valid RRSIG found in the previous step, i.e., that there exists a valid RRSIG
(cryptographically and temporally) for the DNSKEY RRSet generated (cryptographically and temporally) for the DNSKEY RRSet generated
with the private key corresponding to the DNSKEY found in the with the private key corresponding to the DNSKEY found in the
previous step. previous step.
If the validating resolver can successfully complete the steps above, If the validating resolver can successfully complete the steps above,
all DNSKEY RRs in the RRSet ought to be considered authenticated and all DNSKEY RRs in the RRSet ought to be considered authenticated and
can be used to authenticate RRSets at or below the trust anchor. can be used to authenticate RRSets at or below the trust anchor.
There is one exception: if the revoke bit used by the trust anchor
automated update protocol RFC 5011 [RFC5011] is set, the trust anchor
MUST be removed and not used.
If any of the steps above result in an error, the validating resolver If any of the steps above result in an error, the validating resolver
SHOULD log them and abort the verification as specified in section 5 SHOULD log them and abort the verification as specified in section
of RFC 4035 [RFC4035]. 5.5 of RFC 4035 [RFC4035].
If there are multiple trust anchors configured for a zone, any one of If there are multiple trust anchors configured for a zone, any one of
them is sufficient to validate data in the zone. For this reason, them is sufficient to validate data in the zone. For this reason,
old trust anchors SHOULD be removed from a validating resolver's old trust anchors SHOULD be removed from a validating resolver's
trust anchor list soon after the corresponding keys are no longer trust anchor list soon after the corresponding keys are no longer
used by the zone. If there are multiple trust anchors configured for used by the zone, as described in RFC 5011 [RFC5011]. Even if a
a zone, any one of them is sufficient to validate data in the zone. trust anchor is not used in resolution, a validating resolver needs
For this reason, old trust anchors SHOULD be removed from a to query for it frequently enough to detect changes as prescribed in
validating resolver's trust anchor list soon after the corresponding RFC5011.
keys are no longer used by the zone, as described in RFC 5011
[RFC5011].
If a validating resolver is unable to retrieve a signed DNSKEY RRSet If a validating resolver is unable to retrieve a signed DNSKEY RRSet
corresponding to a trust anchor (i.e., prime the trust anchor), it corresponding to a trust anchor (i.e., prime the trust anchor), it
SHOULD log this condition as an error. Inability to prime a zone's SHOULD log this condition as an error. Inability to prime a zone's
trust anchor results in the validating resolver's inability to trust anchor results in the validating resolver's inability to
validate data from the corresponding zone. The validating resolver validate data from the corresponding zone. The validating resolver
MUST treat this zone as bogus, until such time it is able to get a MUST treat this zone as bogus, until such time it is able to get a
DNSKEY set validated by a Trust anchor. The processing of trust DNSKEY set validated by a trust anchor.
anchor and DS from parent errors MUST follow the same rules.
4. Trust Anchor Maintenance 4. Trust Anchor Maintenance
Trust anchors correspond to zones' key signing keys and these keys do Trust anchors usually correspond to zones' key signing keys and these
change in the course of normal operation. It is up to validating keys do change in the course of normal operation. It is up to
resolver operators to ensure that configured trust anchor information validating resolver operators to ensure that configured trust anchor
remains current and does not go stale: each configured trust anchor information remains current and does not go stale: each configured
SHOULD correspond to a DNSKEY RR in the trust anchor zone's apex trust anchor SHOULD correspond to a DNSKEY RR in the trust anchor
DNSKEY RRSet. This process is called trust anchor maintenance. zone's apex DNSKEY RRSet. This process is called trust anchor
(Initial trust anchor configuration requires human intervention to maintenance. (Initial trust anchor configuration requires human
verify the trust anchor's authenticity using out-of-band means and is intervention to verify the trust anchor's authenticity using out-of-
outside the scope of this document.) band means and is outside the scope of this document.)
This section provides a brief overview of some possible mechanisms to This section provides a brief overview of some possible mechanisms to
keep trust anchor information current: keep trust anchor information current:
Manual configuration: The validating resolver operator MAY choose to Manual configuration: The validating resolver operator MAY choose to
maintain trust anchor information completely manually. In this maintain trust anchor information completely manually. In this
case, the operator assumes responsibility for noticing stale trust case, the operator assumes responsibility for noticing stale trust
anchor information (i.e., DS records that no longer point to a anchor information (i.e., DS records that no longer point to a
corresponding DNSKEY RR in the trust anchor zone's apex DNSKEY corresponding DNSKEY RR in the trust anchor zone's apex DNSKEY
RRSet) and updating that information. This process MAY require RRSet) and updating that information. This process MAY require
the operator to use the same out-of-band verification mechanism as the operator to use the same out-of-band verification mechanism as
used for initial configuration to ensure that the new trust anchor used for initial configuration to ensure that the new trust anchor
DS record is trustworthy. Because manual maintenance is DS record is trustworthy. Because manual maintenance is
burdensome and prone to error, and because other automated trust burdensome and prone to error, and because other automated trust
anchor maintenance processes either exist or are in development, anchor maintenance processes either exist or are in development,
manual trust anchor maintenance is NOT RECOMMENDED. manual trust anchor maintenance is NOT RECOMMENDED.
DNSSEC In-band Update: The IETF DNS Extensions Working Group has DNSSEC In-band Update: RFC 5011 [RFC5011] defines an automated way
developed a protocol to automatically update DNSSEC trust anchors, keep DNSSEC trust anchors updated. This protocol relies on a
which is described in RFC 5011 [RFC5011]. This protocol relies on small DNSSEC protocol change (an additional flag in the DNSKEY
a small DNSSEC protocol change (an additional flag in the DNSKEY
record) and can be implemented either in a validating resolver record) and can be implemented either in a validating resolver
itself or in an external program with access to the validating itself or in an external program with access to the validating
resolver's trust anchor configuration data. resolver's trust anchor configuration data.
Trusted update mechanism: Updated trust anchor information MAY be Trusted update mechanism: Updated trust anchor information MAY be
obtained via a trusted non-DNS update mechanism. One possibility obtained via a trusted non-DNS update mechanism. One possibility
is the operating system update mechanism provided by most software is the operating system update mechanism provided by most software
vendors. Operators already place considerable trust in this vendors. Operators already place considerable trust in this
mechanism, so it is reasonable to extend this trust to allow mechanism, so it is reasonable to extend this trust to allow
distribution and update of DNSSEC public key material. Another distribution and update of DNSSEC public key material. Another
possibility is to obtain trust anchor configuration directly from possibility is to obtain trust anchor configuration directly from
the validating resolver software vendor. This mechanism is the validating resolver software vendor. A possible error
realistically only feasible for updating a small number of trust condition in this mechanism is that a machine is brought up with
anchors, such as for the top-level domains. In a public DNSSEC an "old" trust configuration, like when a machine is configured
deployment, the root zone would be signed and only the root's from an old media or brought out of storage. The machines ought
trust anchor would need updating. to be able to detect the fact the list of trust anchors is "out-
of-date" and fetch a more recent update. During this process it
may be necessary to disable DNSSEC and only depend on the keys for
the update mechanism to authorize the changes to the
configuration.
Combination of update mechanisms: It is possible that for a given Combination of update mechanisms: It is possible that for a given
validating resolver, different trust anchors will be maintained by validating resolver, different trust anchors will be maintained by
different mechanisms. For example, some trust anchors might be different mechanisms. For example, some trust anchors might be
kept up to date by a trusted update mechanism and others kept up to date by a trusted update mechanism and others
maintained by some site-specific mechanism. In this case, it is maintained by some site-specific mechanism. In this case, it is
important that the mechanisms maintain a mutually exclusive set of important that the mechanisms maintain a mutually exclusive set of
trust anchors. trust anchors.
The out-of-sync errors described above in the "Trusted update
mechanism" section can occur if the system the validating resolver is
offline or in storage for an extend period or reinstalled.
Trust Anchor Repositories (TAR) are sometimes mentioned at the same
time as a trust anchor configuration. TARs are in essence an
outsourced trust anchor maintenance mechanism, where the user can
avoid maintaining a large set of trust anchors by only configuring
the root zone's key and the TAR key.
5. Security considerations 5. Security considerations
This document proposes a standard format for documenting DNSSEC trust This document proposes a standard format for documenting DNSSEC trust
anchors. Configuration of trust anchors, especially those obtained anchors. Configuration of trust anchors, especially those obtained
from third parties as part of an automated process, is a critical from third parties as part of an automated process, is a critical
security operation. The procedures listed above describe the minimal security operation. The procedures listed above describe the minimal
checks that should be performed and reporting that should be done checks that should be performed and reporting that should be done
when configuring trust anchors. when configuring trust anchors.
In a widespread DNSSEC deployment, the root zone and many TLD zones The root zone is now signed and many TLD's are planning DNSSEC
would be signed, thus greatly reducing the number trust anchors that deployment. This state of affairs greatly reduces the number of
validating resolvers would need to store and keep track of. trust anchors that validating resolvers need to configure and
maintain.
If multiple mechanisms are updating the trust anchor list then there If multiple mechanisms are updating the trust anchor list then there
is the possibility of conflict, such as one mechanism reinserting an is the possibility of conflict, such as one mechanism reinserting an
expired trust anchor. expired trust anchor.
Trust anchors are configuration information. A validating resolver Trust anchors are configuration information. A validating resolver
ought to treat this information differently than DNS data obtained ought to treat this information differently than DNS data obtained
over the network and never use the configured trust anchors as part over the network and never use the configured trust anchors as part
of an answer. of an answer.
skipping to change at page 12, line 8 skipping to change at page 12, line 8
configured to treat responses from the zone as bogus, causing configured to treat responses from the zone as bogus, causing
resolution failures. resolution failures.
6. IANA considerations 6. IANA considerations
This document does not have any IANA actions. This document does not have any IANA actions.
7. Acknowledgments 7. Acknowledgments
This work was undertaken at the suggestion of the DNSSEC Deployment This work was undertaken at the suggestion of the DNSSEC Deployment
working group (www.dnssec-deployment.org). Following people are working group (www.dnssec-deployment.org). The following people are
acknowledged for contributing to this document, Alfred Hoenes, Edward acknowledged for contributing to this document: Alfred Hoenes, Edward
Lewis, Geoff Huston, Paul Hoffman, Matthijs Mekking, Scott Rose Paul Lewis, Wes Hardaker, Geoff Huston, Paul Hoffman, Matthijs Mekking,
Wouters. Scott Rose, Paul Wouters.
8. Normative References 8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "DNS Security Introduction and Requirements", Rose, "DNS Security Introduction and Requirements",
RFC 4033, March 2005. RFC 4033, March 2005.
[RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Resource Records for the DNS Security Extensions", Rose, "Resource Records for the DNS Security Extensions",
skipping to change at page 14, line 5 skipping to change at page 13, line 30
[RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Protocol Modifications for the DNS Security Rose, "Protocol Modifications for the DNS Security
Extensions", RFC 4035, March 2005. Extensions", RFC 4035, March 2005.
[RFC4509] Hardaker, W., "Use of SHA-256 in DNSSEC Delegation Signer [RFC4509] Hardaker, W., "Use of SHA-256 in DNSSEC Delegation Signer
(DS) Resource Records (RRs)", RFC 4509, May 2006. (DS) Resource Records (RRs)", RFC 4509, May 2006.
[RFC5011] StJohns, M., "Automated Updates of DNS Security (DNSSEC) [RFC5011] StJohns, M., "Automated Updates of DNS Security (DNSSEC)
Trust Anchors", RFC 5011, September 2007. Trust Anchors", RFC 5011, September 2007.
8.2. Informative References
[RFC4641] Kolkman, O. and R. Gieben, "DNSSEC Operational Practices",
RFC 4641, September 2006.
Authors' Addresses Authors' Addresses
Matt Larson Matt Larson
VeriSign, Inc. VeriSign, Inc.
21345 Ridgetop Circle 21345 Ridgetop Circle
Dulles, VA 20166-6503 Dulles, VA 20166-6503
USA USA
Email: mlarson@verisign.com Email: mlarson@verisign.com
Olafur Gudmundsson Olafur Gudmundsson
OGUD Consulting LLC Shinkuro Inc.
3821 Village Park Drive 4922 Fairmont Av, Suite 250
Chevy Chase, MD 20815 Bethsda, MD 20814
USA USA
Email: ogud@ogud.com Email: ogud@ogud.com
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