draft-ietf-dnsop-maintain-ds-02.txt   draft-ietf-dnsop-maintain-ds-03.txt 
dnsop O. Gudmundsson dnsop O. Gudmundsson
Internet-Draft CloudFlare Internet-Draft CloudFlare
Intended status: Informational P. Wouters Intended status: Standards Track P. Wouters
Expires: October 6, 2016 Red Hat Expires: December 12, 2016 Red Hat
April 4, 2016 June 10, 2016
Managing DS records from parent via CDS/CDNSKEY Managing DS records from parent via CDS/CDNSKEY
draft-ietf-dnsop-maintain-ds-02 draft-ietf-dnsop-maintain-ds-03
Abstract Abstract
RFC7344 specifies how DNS trust can be partially maintained in-band RFC7344 specifies how DNS trust can be partially maintained in-band
between parent and child. There are two features missing in that between parent and child. There are two features missing in that
specification: initial trust setup and removal of trust anchor. This specification: initial trust setup and removal of trust anchor. This
document addresses both these omissions. document addresses both these omissions.
Changing a domain's DNSSEC status can be a complicated matter Changing a domain's DNSSEC status can be a complicated matter
involving multiple unrelated parties. Some of these parties, such as involving multiple unrelated parties. Some of these parties, such as
the DNS operator, might not even be known by all organizations the DNS operator, might not even be known by all the organizations
involved. The inability to disable DNSSEC via in-band signalling is involved. The inability to disable DNSSEC via in-band signalling is
seen as a problem or liability that prevents some DNSSEC adoption at seen as a problem or liability that prevents some DNSSEC adoption at
large scale. This document adds a method for in-band signalling of large scale. This document adds a method for in-band signalling of
this DNSSEC status changes. these DNSSEC status changes.
Initial trust is considered a much harder problem, this document will Initial trust is considered in general to be a hard technical
seek to clarify and simplify the initial acceptance policy. problem, this document sets forth reasonable policies that clarify
and simplify the initial acceptance policy.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 6, 2016. This Internet-Draft will expire on December 12, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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publication of this document. Please review these documents publication of this document. Please review these documents
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to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Removing a DS Record . . . . . . . . . . . . . . . . . . 3 1.1. Introducing a DS record . . . . . . . . . . . . . . . . . 3
1.2. Introducing a DS record . . . . . . . . . . . . . . . . . 3 1.2. Removing a DS Record . . . . . . . . . . . . . . . . . . 3
1.3. Notation . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3. Notation . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.4. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. The Three Uses of CDS . . . . . . . . . . . . . . . . . . . . 4 2. The Three Uses of CDS . . . . . . . . . . . . . . . . . . . . 4
2.1. The meaning of the CDS RRset . . . . . . . . . . . . . . 5 2.1. The meaning of the CDS RRset . . . . . . . . . . . . . . 5
3. Enabling DNSSEC via CDS/CDNSKEY . . . . . . . . . . . . . . . 5 3. Enabling DNSSEC via CDS/CDNSKEY . . . . . . . . . . . . . . . 5
3.1. Accept policy via authenticated channel . . . . . . . . . 5 3.1. Accept policy via authenticated channel . . . . . . . . . 5
3.2. Accept with extra checks . . . . . . . . . . . . . . . . 5 3.2. Accept with extra checks . . . . . . . . . . . . . . . . 5
3.3. Accept after delay . . . . . . . . . . . . . . . . . . . 6 3.3. Accept after delay . . . . . . . . . . . . . . . . . . . 6
3.4. Accept with challenge . . . . . . . . . . . . . . . . . . 6 3.4. Accept with challenge . . . . . . . . . . . . . . . . . . 6
4. DNSSEC Delete Algorithm . . . . . . . . . . . . . . . . . . . 6 4. DNSSEC Delete Algorithm . . . . . . . . . . . . . . . . . . . 6
5. Security considerations . . . . . . . . . . . . . . . . . . . 7 5. Security considerations . . . . . . . . . . . . . . . . . . . 7
6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 7 6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 7
6.1. Promoting RFC7344 to standards track . . . . . . . . . . 8
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.1. Normative References . . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 8
7.2. Informative References . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . 8
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 8 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
1. Introduction 1. Introduction
CDS/CDNSKEY [RFC7344] records are used to signal changes in trust CDS/CDNSKEY [RFC7344] records are used to signal changes in trust
anchors, this is one method to maintain delegations that can be used anchors. This is one method to maintain delegations that can be used
when the DNS operator has no other way to inform the parent that when the DNS operator has no other way to inform the parent that
changes are needed. [RFC7344] contains no "delete" signal for the changes are needed.
child to tell the parent that it wants to remove the DNSSEC security
for its domain.
[RFC7344] did not include a method for the Initial Trust [RFC7344] is lacking two different options for full automated
establishment and left it to each parent to come up with an operation to be possible. Firstly it did not define a method for the
acceptance policy. Initial Trust establishment and left it to each parent to come up
with an acceptance policy. Secondly it did not provide a "delete"
signal for the child to tell the parent that it wants to remove the
DNSSEC security for its domain.
1.1. Removing a DS Record 1.1. Introducing a DS record
The big issue is how a child domain instructs the parent that it
wants to have a DS record added. This problem can be solved using a
few simplifying assumptions. This document makes the assumption that
there are reasonable policies that can be applied and will allow
automation of trust introduction.
Not being able to enable trust via an easily automated mechanism is
hindering DNSSEC at scale for DNS hosters that do not have automated
access to the "registry" of the child zone's parent.
1.2. Removing a DS Record
This document introduces the delete option for both CDS and CDNSKEY, This document introduces the delete option for both CDS and CDNSKEY,
allowing a child to signal to the parent to turn off DNSSEC. When a allowing a child to signal to the parent to turn off DNSSEC. When a
domain is moved from one DNS operator to another one, sometimes it is domain is moved from one DNS operator to another one, sometimes it is
necessary to turn off DNSSEC to facilitate the change of DNS necessary to turn off DNSSEC to facilitate the change of DNS
operator. Common scenarios include: operator. Common scenarios include:
1 alternative to doing a proper DNSSEC algorithm rollover due to 1 alternative to doing a proper DNSSEC algorithm rollover due to
operational limitations such as software limitations. operational limitations such as software limitations.
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algorithms to sign the zone, thus an algorithm rollover can not be algorithms to sign the zone, thus an algorithm rollover can not be
performed. performed.
5 the domain holder no longer wants DNSSEC enabled. 5 the domain holder no longer wants DNSSEC enabled.
The lack of a "remove my DNSSEC" option is cited as a reason why some The lack of a "remove my DNSSEC" option is cited as a reason why some
operators cannot deploy DNSSEC, as this is seen as an operational operators cannot deploy DNSSEC, as this is seen as an operational
risk. risk.
Turning off DNSSEC reduces the security of the domain and thus should Turning off DNSSEC reduces the security of the domain and thus should
only be done carefully, and that decision should be fully under the only be done carefully, and that decision SHOULD be fully under the
child domain's control. child domain's control.
1.2. Introducing a DS record
The converse issue is how a child domain instructs the parent that it
wants to have a DS record added. This problem can be solved using a
few simplifying assumptions. This document makes the assumption that
there are reasonable policies that can be applied and will allow
automation of trust introduction.
Not being able to enable trust via an easily automated mechanism is
hindering DNSSEC at scale for DNS hosters that do not have automated
access to the "registry" of the child zone's parent.
1.3. Notation 1.3. Notation
When this document uses the word CDS it implies that the same applies When this document uses the word CDS it implies that the same applies
to CDNSKEY and vice versa. The only difference between the two to CDNSKEY and vice verse. The only differences between the two
records is how information is represented. records is how information is represented, and who calculates the DS
digiest.
We use RRR to mean Registry Registrar Registrant in the context of We use RRR to mean Registry Registrar Registrant in the context of
DNS domain markets. DNS domain markets.
When the document uses the word "parent" it implies an entity that is When the document uses the word "parent" it implies an entity that is
authorized to insert DS records into the parent zone on behalf of the authorized to insert DS records into the parent zone on behalf of the
child domain. Which entity this exactly is does not matter. It child domain. Which entity this exactly is does not matter. It
could be the Registrar or Reseller that the child domain was could be the Registrar or Reseller that the child domain was
purchased from. It could be the Registry that the domain is purchased from. It could be the Registry that the domain is
registered in when allowed. It could be some other entity when the registered in when allowed. It could be some other entity when the
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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 [RFC2119]. document are to be interpreted as described in [RFC2119].
2. The Three Uses of CDS 2. The Three Uses of CDS
In general there are three operations that a domain wants to In general there are three operations that a domain wants to
influence on its parent: influence on its parent:
1 Roll over KSK, this means updating the DS records in the parent to 1 Enable DNSSEC validation, i.e. place an initial DS RRset in the
parent.
2 Roll over KSK, this means updating the DS records in the parent to
reflect the new set of KSK's at the child. This could be an ADD reflect the new set of KSK's at the child. This could be an ADD
operation, a DELETE operation on one or more records while keeping operation, a DELETE operation on one or more records while keeping
at least one DS RR, or a full REPLACE operation. at least one DS RR, or a full REPLACE operation.
2 Turn off DNSSEC validation, i.e. delete all the DS records. 3 Turn off DNSSEC validation, i.e. delete all the DS records.
3 Enable DNSSEC validation, i.e. place an initial DS RRset in the
parent.
Operation 1 is covered in [RFC7344], operations 2 and 3 are defined Operation 2 is covered in [RFC7344], operations 1 and 3 are defined
in this document. In many people's minds, those two later operations in this document. In many people's minds, those two operations carry
carry more risk than the first one. This document argues that 2 is more risk than the first one. This document argues that 3 is
identical to 1 and the third one is different (but not that identical to 2 and the first one is different (but not that
different). different).
2.1. The meaning of the CDS RRset 2.1. The meaning of the CDS RRset
The semantic meaning of publishing a CDS RRset is interpreted to The semantic meaning of publishing a CDS RRset is interpreted to
mean: mean:
"Publishing a CDS or CDNSKEY record signals to the parent that the "Publishing a CDS or CDNSKEY record signals to the parent that the
child desires that the corresponding DS records be synchronized. child desires that the corresponding DS records be synchronized.
Every parent or parental agent should have an acceptance policy of Every parent or parental agent should have an acceptance policy of
these records for the three different use cases involved: Initial DS these records for the three different use cases involved: Initial DS
publication, Key rollover, and Returning to Insecure." publication, Key rollover, and Returning to Insecure."
In short, the CDS RRset is an instruction to the parent to modify the In short, the CDS RRset is an instruction to the parent to modify the
DS RRset if the CDS and DS RRsets differ. The acceptance policy for DS RRset if the CDS and DS Reset's differ. The acceptance policy for
CDS in the rollover case is "seeing" according to [RFC7344]. The CDS in the rollover case is "seeing" according to [RFC7344]. The
acceptance policy in the Delete case is seeing a (validly signed) CDS acceptance policy in the Delete case is seeing a (validly signed) CDS
RRset with the delete operation specified in this document. RRset with the delete operation specified in this document.
3. Enabling DNSSEC via CDS/CDNSKEY 3. Enabling DNSSEC via CDS/CDNSKEY
There are number of different models for managing initial trust, but There are number of different models for managing initial trust, but
in the general case, the child wants to enable global validation for in the general case, the child wants to enable global validation for
the future. Thus during the period from the time the child publishes the future. Thus during the period from the time the child publishes
the CDS until the corresponding DS is published at the parent is the the CDS until the corresponding DS is published at the parent is the
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DNSSEC information to the parent, so the parent can publish a DS DNSSEC information to the parent, so the parent can publish a DS
record for the child. In this case there is a possibility of setting record for the child. In this case there is a possibility of setting
up some kind of authentication mechanism and submission mechanism up some kind of authentication mechanism and submission mechanism
that is outside the scope of this document. that is outside the scope of this document.
Below are some policies that parents can use. These policies assume Below are some policies that parents can use. These policies assume
that the notifications can be verified or authenticated. that the notifications can be verified or authenticated.
3.1. Accept policy via authenticated channel 3.1. Accept policy via authenticated channel
In this case the parent is notified via UI/API that a CDS RRset In this case the parent is notified via authenticated channel UI/API
exists. The parent retrieves the CDS and inserts the corresponding that a CDS/CDNSKEY RRset exists. In the case of a CDS RRset the
DS RRset as requested, provided that the request comes over an parent retrieves the CDS and inserts the corresponding DS RRset as
authenticated channel. requested. In the case of CDNSKEY the parent retrieves the CDNSKEY
RRset and calculates the DS record(s).
3.2. Accept with extra checks 3.2. Accept with extra checks
In this case the parent checks that the source of the notification is In this case the parent checks that the source of the notification is
allowed to request the DS insertion. The checks could include allowed to request the DS insertion. The checks could include
whether this is a trusted entity, whether the nameservers correspond whether this is a trusted entity, whether the nameservers correspond
to the requestor, whether there have been any changes in registration to the requester, whether there have been any changes in registration
in the last few days, etc. The parent can also send a notification in the last few days, etc. The parent can also send a notification
requesting a confirmation. requesting a confirmation, for example by sending email to the
registrant requesting a confirmation. The end result is that the CDS
The end result is that the CDS RRset is accepted at the end of the RRset is accepted at the end of the checks or when the out-of-band
checks or when the out-of-band confirmation is received. confirmation is received.
3.3. Accept after delay 3.3. Accept after delay
In this case, if the parent deems the request valid, it starts In this case, if the parent deems the request valid, it starts
monitoring the CDS RRset at the child nameservers over period of time monitoring the CDS RRset at the child nameservers over period of time
to make sure nothing changes. After some time or after a number of to make sure nothing changes. After some time or after a number of
checks, preferably from different vantage points in the network, the checks, preferably from different vantage points in the network, the
parent accepts the CDS RRset as a valid signal to update its DS RRset parent accepts the CDS RRset as a valid signal to update its DS RRset
for this child. for this child.
3.4. Accept with challenge 3.4. Accept with challenge
In this case the parent instructs the requestor to insert some record In this case the parent instructs the requester to insert some record
into the child domain to prove it has the ability to do so (i.e., it into the child domain to prove it has the ability to do so (i.e., it
is the operator of the zone). is the operator of the zone).
4. DNSSEC Delete Algorithm 4. DNSSEC Delete Algorithm
The DNSKEY algorithm registry contains two reserved values: 0 and The DNSKEY algorithm registry contains two reserved values: 0 and
255[RFC4034]. The CERT record [RFC4398] defines the value 0 to mean 255[RFC4034]. The CERT record [RFC4398] defines the value 0 to mean
the algorithm in the CERT record is not defined in DNSSEC. the algorithm in the CERT record is not defined in DNSSEC.
[rfc-editor remove before publication] For this reason, using the For this reason, using the value 0 in CDS/CDNSKEY delete operations
value 0 in CDS/CDNSKEY delete operations is potentially problematic, is potentially problematic, but we propose it here anyway as the risk
but we propose it here anyway as the risk is minimal. The is minimal. The alternative is to reserve a DNSSEC algorithm number
alternative is to reserve a DNSSEC algorithm number for this purpose. for this purpose.
[rfc-editor end remove]
Right now, no DNSSEC validator understands algorithm 0 as a valid Right now, no DNSSEC validator understands algorithm 0 as a valid
signature algorithm. If a validator sees a DNSKEY or DS record with signature algorithm. If a validator sees a DNSKEY or DS record with
this algorithm value, it MUST treat it as unknown. Accordingly, the this algorithm value, it MUST treat it as unknown. Accordingly, the
zone is treated as unsigned unless there are other algorithms zone is treated as unsigned unless there are other algorithms
present. present. In general the value 0 should never be used in the context
of DNSKEY and DS records.
In the context of CDS and CDNSKEY records, DNSSEC algorithm 0 is In the context of CDS and CDNSKEY records, DNSSEC algorithm 0 is
defined to mean that the entire DS RRset MUST be removed. The defined to mean that the entire DS RRset MUST be removed. The
contents of the CDS or CDNSKEY RRset MUST contain one RR and only contents of the CDS or CDNSKEY RRset MUST contain one RR and only
contain the fixed fields as shown below. contain the exactly the fields as shown below.
1 CDS 0 0 0 1 CDS 0 0 0
2 CDNSKEY 0 3 0 2 CDNSKEY 0 3 0
The keying material payload is represented by a single 0. This The keying material payload is represented by a single 0. This
record is signed in the same way as regular CDS/CDNSKEY RRsets are record is signed in the same way as regular CDS/CDNSKEY RRset's are
signed. signed. This is a change in format from strict interpretation of
[RFC7344] and may cause problems with some deployed software.
Strictly speaking the CDS record could be "CDS X 0 X" as only the Strictly speaking the CDS record could be "CDS X 0 X" as only the
DNSKEY algorithm is what signals the DELETE operation, but for DNSKEY algorithm is what signals the DELETE operation, but for
clarity the "0 0 0" notation is mandated - this is not a definition clarity the "0 0 0" notation is mandated - this is not a definition
of DS Digest algorithm 0. The same argument applies to "CDNSKEY 0 3 of DS Digest algorithm 0. The same argument applies to "CDNSKEY 0 3
0", the value 3 in second field is mandated by RFC4034 section 2.1.2. 0", the value 3 in second field is mandated by RFC4034 section 2.1.2.
Once the parent has verified the CDS/CDNSKEY RRset and it has passed Once the parent has verified the CDS/CDNSKEY RRset and it has passed
other acceptance tests, the parent MUST remove the DS RRset. After other acceptance tests, the parent MUST remove the DS RRset. After
waiting a sufficient amount of time - depending on the parental TTLs waiting a sufficient amount of time - depending on the parental TTL's
- the child can start the process of turning off DNSSEC. - the child can start the process of turning off DNSSEC.
5. Security considerations 5. Security considerations
This document's main goal is to avoid validation failures when a This document's main goal is to avoid validation failures when a
domain moves from one DNS operator to another. Turning off DNSSEC domain moves from one DNS operator to another. Turning off DNSSEC
reduces the security of the domain and thus should only be done as a reduces the security of the domain and thus should only be done as a
last resort. last resort.
In most cases it is preferable that operators collaborate on the In most cases it is preferable that operators collaborate on the
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can be hard and takes a long time. Before deciding to complete the can be hard and takes a long time. Before deciding to complete the
rollover via an unsigned state, all options SHOULD be considered. rollover via an unsigned state, all options SHOULD be considered.
A parent SHOULD ensure that when it is allowing a child to become A parent SHOULD ensure that when it is allowing a child to become
securely delegated, that it has a reasonable assurance that the CDS/ securely delegated, that it has a reasonable assurance that the CDS/
CDNSKEY RRset that is used to bootstrap the security is visible from CDNSKEY RRset that is used to bootstrap the security is visible from
a geographically and topologically diverse view. It SHOULD also a geographically and topologically diverse view. It SHOULD also
ensure that the zone validates correctly if the parent publishes the ensure that the zone validates correctly if the parent publishes the
DS record. A parent zone might also consider sending an email to its DS record. A parent zone might also consider sending an email to its
contact addresses to give the child zone a warning that security will contact addresses to give the child zone a warning that security will
be enabled after a certain about of wait time - thus allowing a child be enabled after a certain amount of wait time - thus allowing a
administrator to cancel the request. child administrator to cancel the request.
6. IANA considerations 6. IANA considerations
This document updates the following IANA registries: "DNS Security This document updates the following IANA registries: "DNS Security
Algorithm Numbers" Algorithm Numbers"
Algorithm 0 adds a reference to this document. Algorithm 0 adds a reference to this document.
6.1. Promoting RFC7344 to standards track
Experience has shown that CDS/CDNSKEY are useful in the deployment of
DNSSEC. [RFC7344] was published as Informational, this document
elevates RFC7344 to standards track.
7. References 7. References
7.1. Normative References 7.1. Normative References
[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",
RFC 4034, DOI 10.17487/RFC4034, March 2005, RFC 4034, DOI 10.17487/RFC4034, March 2005,
<http://www.rfc-editor.org/info/rfc4034>. <http://www.rfc-editor.org/info/rfc4034>.
[RFC7344] Kumari, W., Gudmundsson, O., and G. Barwood, "Automating [RFC7344] Kumari, W., Gudmundsson, O., and G. Barwood, "Automating
skipping to change at page 8, line 33 skipping to change at page 8, line 39
RFC2119, March 1997, RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <http://www.rfc-editor.org/info/rfc2119>.
[RFC4398] Josefsson, S., "Storing Certificates in the Domain Name [RFC4398] Josefsson, S., "Storing Certificates in the Domain Name
System (DNS)", RFC 4398, DOI 10.17487/RFC4398, March 2006, System (DNS)", RFC 4398, DOI 10.17487/RFC4398, March 2006,
<http://www.rfc-editor.org/info/rfc4398>. <http://www.rfc-editor.org/info/rfc4398>.
Appendix A. Acknowledgements Appendix A. Acknowledgements
This document is generated using the mmark tool that Miek Gieben has This document is generated using the mmark tool that Miek Gieben has
developed. developed. We thank number of people that have provided feedback and
useful comments including Bob Harold, John Levine, Matthijs Mekking,
Dan York, Shane Kerr, Jacques Latour.
Authors' Addresses Authors' Addresses
Olafur Gudmundsson Olafur Gudmundsson
CloudFlare CloudFlare
Email: olafur+ietf@cloudflare.com Email: olafur+ietf@cloudflare.com
Paul Wouters Paul Wouters
Red Hat Red Hat
Email: pwouters@redhat.com Email: pwouters@redhat.com
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