4 INTERNET-DRAFT S. Daniel Park
5 Expires: October 2003 Syam Madanapalli
6 File: SAMSUNG Electronics
7 draft-park-ipv6-extensions-dns-pnp-00.txt April 2003
12 IPv6 Extensions for DNS Plug and Play
18 This document is an Internet-Draft and is in full conformance with
19 all provisions of Section 10 of RFC2026.
21 Internet-Drafts are working documents of the Internet Engineering
22 Task Force (IETF), its areas, and its working groups. Note that
23 other groups may also distribute working documents as
26 Internet-Drafts are draft documents valid for a maximum of six
27 months and may be updated, replaced, or obsoleted by other
28 documents at any time. It is inappropriate to use Internet-Drafts
29 as reference material or to cite them other than as "work in
32 The list of current Internet-Drafts can be accessed at
33 http://www.ietf.org/ietf/1id-abstracts.txt
35 The list of Internet-Draft Shadow Directories can be accessed at
36 http://www.ietf.org/shadow.html.
42 This document proposes automatic configuration of domain name (FQDN)
43 for IPv6 nodes using Domain Name Auto-Configuration (called 6DNAC) as
44 a part of IPv6 plug and play feature. 6DNAC allows the automatic
45 registration of domain name and corresponding IPv6 Addresses with
46 the DNS server. In order to provide 6DNAC function, Neighbor Discovery
47 Protocol [2461] will be used. Moreover, 6DNAC does not require any
48 changes to the existing DNS system.
53 1. Introduction ............................................. 3
54 2. Terminology .............................................. 3
55 3. 6DNAC Design Principles .................................. 4
56 4. 6DNAC Overview ........................................... 4
57 5. 6DNAC Requirements ....................................... 5
58 5.1. 6DANR Client Requirements ................................ 5
59 5.2. 6DNAC Server Requirements ................................ 6
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65 6. 6DNAC Messages and Option Formats ........................ 6
66 6.1. Router Advertisement (RA) Message Format ................. 6
67 6.2. Neighbor Solicitation (NS) Message Format ................ 7
68 6.3. Neighbor Advertisement (NA) Message Format ............... 8
69 6.4. Option Formats ........................................... 8
70 6.4.1. DNS Zone Suffix Information Option Format ................ 8
71 6.4.2. Domain Name (FQDN) Option Format ......................... 9
72 6.4.3. Router Alert Option for 6DNAC ............................ 10
73 7. 6DNAC Operation .......................................... 10
74 7.1. 6DNAC Network Topology ................................... 11
75 7.2. 6DNAC Operational Scenarios .............................. 12
76 7.2.1. Domain Name Registration-Success Case .................... 12
77 7.2.2. Domain Name Registration-with DupAddrDetectTransmits=2.... 14
78 7.2.3. Domain Name Registration-Defend Case ..................... 16
79 7.2.4. Domain Name Registration in Retry Mode ................... 19
80 7.2.5. Domain Name Registration when DAD Fails .................. 20
81 7.3. DNS Zone Suffix Discovery and FQDN Construction .......... 22
82 7.3.1. Sending Router Advertisement Messages .................... 22
83 7.3.2. Processing Router Advertisement Messages ................. 22
84 7.3.3. FQDN Lifetime expiry ..................................... 23
85 7.3.4. Host Naming Algorithm .................................... 23
86 7.4. Duplicate Domain Name Detection .......................... 23
87 7.4.1. DAD with All Nodes Multicast Address ..................... 24
88 7.4.1.1. Sending Neighbor Solicitation Messages ................... 24
89 7.4.1.2. Processing Neighbor Solicitation Messages ................ 24
90 7.4.1.3. Sending Neighbor Advertisement Messages .................. 25
91 7.4.1.4. Processing Neighbor Advertisement Messages ............... 25
92 7.4.1.5. Pros and Cons ............................................ 25
93 7.4.2. DAD with Router Alert Option for 6DNAC ................... 25
94 7.4.2.1. Sending Neighbor Solicitation Messages ................... 25
95 7.4.2.2. Processing Neighbor Solicitation Messages ................ 26
96 7.4.2.3. Sending Neighbor Advertisement Messages .................. 26
97 7.4.2.4. Processing Neighbor Advertisement Messages ............... 26
98 7.4.2.5. Pros and Cons ............................................ 26
99 7.4.3. Explicit Detection of Duplicate Domain Name .............. 26
100 7.4.3.1. Sending Neighbor Solicitation Messages ................... 26
101 7.4.3.2. Processing Neighbor Solicitation Messages ................ 26
102 7.4.3.3. Sending Neighbor Advertisement Messages .................. 27
103 7.4.3.4. Processing Neighbor Advertisement Messages ............... 27
104 7.4.3.5. Pros and Cons ............................................ 27
105 7.4.4. Retry Mode for Re-registering Domain Name ................ 27
106 7.5. Domain Name Registration ................................. 27
107 8. Security Consideration ................................... 27
108 9. IANA Consideration ....................................... 28
109 10. Acknowledgement .......................................... 28
110 11. Intellectual Property .................................... 28
111 12. Copyright ................................................ 28
112 13. References ............................................... 29
113 14. Author's Addresses ....................................... 30
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128 Today, most networks use DNS[1034][1035] for convenience. In case of
129 IPv6, DNS is more important element because of IPv6 long addresses
130 which are difficult to remember. In addition, small networks like home
131 networks using IPv6, should be able to make network easily without
132 manual configuration. Also, these small networks may not have DHCP
133 Server, DNS Server etc. that are used to configure the network. This
134 document discusses IPv6 Domain Name Auto-Configuration(6DNAC) procedure
135 for generating and registering the Domain Name and IPv6 addresses with
136 the DNS Server automatically. In order to use 6DNAC, IPv6 nodes are
137 required to implement lightweight functions specified in this document.
138 6DNAC can be applied to all defined IPv6 unicast addresses except Link
139 local IPv6 addresses, viz: Site-local and Global addresses.
141 6DNAC uses Neighbor Discovery Protocol [2461] with new additions
142 (defined in section 6) and DAD procedures for generating and
143 registering the Domain Name with the DNS server automatically.
148 6DNAC - IPv6 Domain Name Auto Configuration. It can provide
149 IPv6 hosts with Domain Name Generation and
150 Registration automatically.
152 6DNAC Client - An IPv6 node that can generate its own unique Domain
153 Name. Section 3 identifies the new requirements that
154 6DNAC places on an IPv6 node to be a 6DNAC node.
156 6DNAC Server - An IPv6 node that can collect and registrate Domain
157 Name and IPv6 addresses automatically. 6DNAC server
158 uses the information from the DAD operation messages
159 with newly defined options for the registration of the
160 Domain Name and IPv6 Addresses. Section 3 identifies
161 the new requirements that 6DNAC places on an IPv6
162 node to be a 6DNAC server. Also 6DNAC server can have
163 various other functions depending on network
164 environment and the network operator. For instance
165 6DNAC Server can acts as a Gateway as well Home Server
168 DAD - Duplicate Address Detection (is defined [2461])
170 DFQDND - Duplicate Domain Name Detection
172 FQDN - Fully Qualified Domain Name - FQDN and Domain Name are
173 used interchangeably in this document.
175 NA - Neighbor Advertisement message (is defined [2461])
177 NS - Neighbor Solicitation message (is defined [2461])
179 RA - Router Advertisement message (is defined [2461])
181 SLAAC - Stateless Address Autoconfiguration [2462].
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187 3. 6DNAC Design Principles
189 This section discusses the design principles of 6DNAC mechanism.
191 1. The new procedures for plug and play DNS should not cause changes
192 to existing DNS system. 6DNAC requires lightweight functions to be
193 implemented only at the client side of the DNS system, and uses the
194 existing DDNS UPDATE [2136] to communicate with DNS Servers.
196 2. Introducing a new protocol will always introduce new problems.
197 6DNAC uses the existing protocols NDP [2461] with minor extensions
198 for generating and registering the domain name automatically
199 without defining a new protocol
201 3. Reusing proven and well understood design principles/patterns
202 will always yield a robust system. 6DNAC is based on IPv6 Address
203 Auotoconfiguration principle, where routers advertise the prefix
204 and host adds the interface ID to the prefix and forms the IPv6
205 address. Domain Name (FQDN) also contains two parts: host name
206 and DNS zone suffix. Routers can advertise the DNS zone suffix
207 on a particular link in Router Advertisements (RA Messages) and
208 hosts can prefix their preferred host name to the DNS zone suffix
209 and form the fully qualified domain name. Also the detection of
210 duplicate domain name is similar to Duplicate Address Detection
211 (DAD) and can be part of DAD operation itself.
216 6DNAC proposes minor extensions to NDP [2461] for automatic generation
217 and registration of domain name with the DNS server. It introduces two
218 new options: DNS Zone Suffix and Fully Qualified Domain Name. DNS Zone
219 Suffix option is carried in Router Advertisement (RA) messages for
220 notifying IPv6 nodes about the valid DNS Zone Suffix on the link and
221 FQDN option in Neighbor Solicitation (NS) and Neighbor Advertisement
222 (NA) messages to detect duplicate domain name. 6DNAC consists of two
223 components: 6DNAC Client and 6DNAC Server. 6DNAC Clients generate the
224 domain name based on DNS Zone Suffix using Host Naming Algorithm (see
225 section 7.3.1) and 6DNAC Server collects and registers the DNS
226 information with the DNS Server on behalf of 6DNAC Clients.
228 The automatic configuration of domain name using 6DNAC consists of
231 - DNS Zone Suffix Discovery and FQDN Construction:
233 IPv6 Nodes collect DNS Zone Suffix information from Router
234 Advertisements and constructs FQDN by prefixing host name to the
235 DNS Zone Suffix. The IPv6 Nodes are required to implement Host
236 Naming Algorithm for generating host part of the FQDN in the
237 absence of administrator.
239 Generation of node's FQDN within the node itself has advantages. Nodes
240 can provide forward and reverse name lookups independent of the DNS
241 System by sending queries directly to IPv6 nodes [NIQ]. Moreover Domain
242 Name is some thing that is owned by the node.
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248 - Duplicate Domain Name Detection
250 All nodes are expected to go for DAD for all new IPv6 unicast
251 addresses, regardless of whether they are obtained through
252 stateful, stateless or manual configuration. 6DNAC uses the DAD
253 messages with new option for carrying the Domain Name along with
254 the new IPv6 Address. 6DNAC Server captures this information and
255 updates DNS Server provided that the IPv6 Address and its domain
256 name are not duplicate. If the domain name is already in use,
257 the 6DNAC server replies to the sender with FQDN Option in NA
258 message indicating that the domain name is duplicate. Then the
259 node is expected to generate another domain name using host
260 naming algorithm and go for DAD. This time the DAD is only for
261 duplicate domain name detection (DFQDND). In order to avoid
262 confusion with the normal NDP processing, the target address
263 field of the NS message must carry the unspecified address
264 in retry mode. This can be repeated depending on number of
265 retries defined by the administrator in the host naming algorithm.
268 - Domain Name Registration
270 6DNAC Server detects the DNS information (IPv6 Address and
271 corresponding FQDN) from DAD/DFQDND messages and updates DNS
272 Server using existing protocol DDNS UPDATE [2136] provided that
273 the IPv6 Address and its domain name are not duplicate.
275 If an IPv6 Address is duplicate, the IPv6 node cannot perform
276 stateless address autoconfiguration repeatedly. Unlike IPv6 stateless
277 address autoconfiguration, 6DNAC allows the automatic configuration of
278 domain name repeatedly if the domain name is duplicate depending on
279 number of retries defined by the administrator in the host naming
283 5. 6DNAC Requirements
285 Depending on the 6DNAC functionality, the IPv6 nodes implement, they
286 are called either 6DNAC Clients or 6DNAC Servers. The following
287 sections lists the requirements that the 6DNAC Client and 6DNAC server
291 5.1. 6DANC Client Requirements
293 - 6DNAC Client must recognize and process the following NDP
296 - DNS Zone Suffix option in RA messages for generating its
299 - Domain Name option in NS and NA messages for detecting
300 the duplicate domain name
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309 - It must generate its domain name (FQDN) based on the DNS
310 suffix that it got from the router advertisement. And it must
311 have a host naming algorithm for generating the host part of
314 - If NA message is received with unspecified target address and
315 FQDN option, then the node must treat that the domain is
319 5.2. 6DNAC Server Requirements
321 - 6DNAC Server must recognize and process the following NDP
324 - If the 6DNAC Server is a router on the link, then it
325 must advertise DNS Zone Suffix option in RA messages
326 for hosts to generate their domain name (FQDN).
328 - FQDN option in NS messages for detecting new DNS
329 information for of nodes on the link for which it
330 must update the AAAA RR and PTR RR in DNS Server.
332 - FQDN option in NA messages for notifying duplicate
333 domain name with unspecified target address.
335 - 6DNAC server must update the DNS Server (both AAAA RR and
336 PTR RR) dynamically using DDNS UPDATE [2136].
338 - 6DNAC server must cache this (newly detected) FQDN, Link
339 Layer Address, and IPv6 Address information, so that it can
340 decide whether it really needs to update DNS Server or not,
341 to avoid redundant updates. This information will also be
342 used for notifying the duplicate domain name.
345 6. 6DNAC Messages and Option Formats
347 In order to achieve the plug and play DNS, 6DNAC proposes new
348 extensions to the NDP [2461]. This section specifies the new
349 additions to NDP messages and formats of new options.
352 6.1. Router Advertisement (RA) Message Format
354 Routers send out Router Advertisement (RA) message periodically, or
355 in response to a Router Solicitation. 6DNAC does not modify the format
356 of the RA message, but proposes new option (DNS Zone Suffix Information)
357 to be carried in RA messages.
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371 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
372 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
373 | Type | Code | Checksum |
374 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
375 | Cur Hop Limit |M|O| Reserved | Router Lifetime |
376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
378 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
380 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
383 | DNS Zone Suffix Information |
385 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
388 <Figure: 1 RA message>
392 6.2. Neighbor Solicitation (NS) Message Format
394 6DNAC does not modify the format of the Neighbor Solicitation (NS)
395 message, but proposes new option (FQDN Option) to be carried in NS
396 messages. When a node is going for DAD, the node must include FQDN
397 option in NS message to participate in plug and play DNS. If the
398 node is going for Explicit Detection of Duplicate Domain Name, the
399 node must use FQDN option in NS message and unspecified address in
400 the target address field.
404 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
406 | Type | Code | Checksum |
407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
409 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
417 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
422 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
425 <Figure: 2 NS message>
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431 6.3. Neighbor Advertisement (NA) Message Format
433 6DNAC does not modify the format of the Neighbor Advertisement (NA)
434 message, but proposes new option (FQDN Option) to be carried in NA
435 messages. 6DNAC Server sends NA message with FQDN option to 6DNAC
436 Client that is performing duplicate domain name detection in case
437 the domain name found to be duplicate.
440 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
441 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
442 | Type | Code | Checksum |
443 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
445 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
453 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
458 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
461 <Figure: 3 NA message>
466 6.4.1. DNS Zone Suffix Information Option Format
468 IPv6 nodes require DNS Zone Suffix for constructing their FQDN.
469 6DNAC introduces new option for routers to advertise the DNS Zone
470 Suffix Information for IPv6 nodes on the link. The suffix information
471 should be configured into routers manually.
474 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
475 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
476 | Type | Length | Reserved |
477 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
479 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
483 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
486 <Figure: 4 DNS Zone Suffix Information>
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494 Length 8-bit unsigned integer. The length of the option
495 (including the type and length fields) in units of
498 Reserved This field is unused. It must be initialized to zero
499 by the sender and must be ignored by the receiver.
501 Valid Life Time 32-bit signed integer. The maximum time, in
502 seconds, over which this suffix is valid. Nodes
503 should treat this as the life time for their domain
504 name. Nodes should contact the source of this
505 information before expiry of this time interval.
506 A value of all one bits (0xFFFFFFFF) represents
509 DNS Zone Suffix The suffix part of the FQDN. The data in the DNS
510 Zone Suffix field should be encoded according to
511 DNS encoding rules specified in [1035].
515 6.4.2. Domain Name (FQDN) Option Format
519 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
520 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
521 | Type | Length | Reserved |
522 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
524 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
528 + FQDN Target Address +
532 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
536 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
539 <Figure: 5 FQDN Information>
543 Length 8-bit unsigned integer. The length of the option
544 (including the type and length fields) in units
545 of 8 octets. It must be greater than 3.
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553 Reserved This field is unused. It must be initialized to
554 zero by the sender and must be ignored by the
557 Valid Life Time 32-bit signed integer. The maximum time, in
558 seconds, over which this domain name is valid
559 6DNAC should deregister this domain name at
560 the expiry of this interval. 6DNAC clients
561 should send updates by the expiry of this
562 interval. A value of all one bits (0xFFFFFFFF)
565 FQDN Target Address The Address for which the FQDN maps to. It
566 should be same as Target Address field of the
567 NS message in case of DAD & duplicate FQDN are
570 Domain Name The domain name (FQDN) of the node. The data in
571 the domain name should be encoded according to
572 DNS encoding rules specified in [1035].
575 6.4.3. Router Alert Option for 6DNAC
577 Router Alert Option for 6DNAC is new option within the IPv6 Hop-by-Hop
578 Header for using in NDP messages. The presence of this option in NS
579 message informs the router that this NS message is carrying Domain
580 Name information and must be processed by the 6DNAC Server on the router.
581 6DNAC Clients can use this option for sending DAD packets instead
582 of addressing the DAD packets to the all-nodes multicast address
583 when 6DNAC Server is implemented on router.
585 The Router Alert option has the following format:
587 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
588 |0 0 0|0 0 1 0 1|0 0 0 0 0 0 1 0| Value (2 octets) |
589 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
592 Values are registered and maintained by the IANA. For 6DNAC, the
593 value has to be assigned by IANA.
595 Further information about this option can be obtained from
596 IPv6 Router Alert Option [2711].
601 6DNAC provides mechanisms for automatic generation of domain name
602 and registering it with the DNS Server for IPv6 nodes. 6DNAC consists
603 of two components: 6DNAC Client and 6DNAC Server. All nodes that want
604 to participate in plug and play DNS are required to implement 6DNAC
605 Client functionality, and one of the IPv6 nodes is required to
606 implement 6DNAC Server functionality. The IPv6 node that implements
607 the 6DNAC Server functionality must know the location of the DNS
608 Server and must be a trusted node to send DDNS UPDATE [2136] messages.
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614 7.1. 6DNAC Network Topology
616 This section identifies the possible locations for the 6DNAC Server.
617 Note that, all nodes are required to implement 6DNAC Client
618 functionality for constructing the domain name from the DNS Zone
619 Suffix Information advertised by the router. Figure 6 illustrates
620 IPv6 host (H4) implementing 6DNAC Server functionality. In this case
621 H4 can serve only one link (that it belongs to) for automatic
622 registration of domain name. H4 must observe the DAD packets on the
623 link to detect the DNS information, this requires all nodes on the
624 link must belong to same solicited node multicast address. In general,
625 this may not be the case. So the node that is going for DAD must use
626 all nodes multicast address for DAD packets, so that the 6DNAC Server
627 (H4) can observe the DAD packets, detects IPv6 address and
628 corresponding domain name, checks if this domain name is duplicate
629 and finally registers the domain name with the DNS Server.
633 +---+ +---+ +----------+
634 | H1| | H4|<--- DDNS UPDATE --->|DNS Server|
635 +-+-+ +-+-+ +----+-----+
638 ---+-----+-----------+-----+-----------+ R1 +-----+
646 H1, H2, H3 - 6DNAC Clients
651 <Figure: 6 Example of 6DNAC Topology>
654 Figure 7 shows the 6DNAC Server implemented on a router R1. In this
655 case a single 6DNAC server can serve multiple links for automatic
656 configuration of the domain name. This topology also has flexibility
657 of using DAD packets with Router Alert option instead of sending DAD
658 packets to all nodes multicast address. The routers are required to
659 process all the packets with Router Alert option as per [2711].
661 In case of Home Networks, R1 is will acts as a Home Gateway (CPE)
662 connected to ISP. R1 delegates the prefix from the ISP edge router.
663 After delegating the prefix the CPE can advertise the DNS Zone suffix
664 along with the prefix information to the nodes on the links to which
665 the router is connected to. Note that the R1 must be configured with
666 the DNS Zone suffix Information manually.
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680 +---+ ---+--------+--+-- +----------+
685 ---+-----+------------------+ R1 +---------+
693 H1, H2 - 6DNAC Clients on Link1
694 H3, H4 - 6DNAC Clients on Link2
695 R1 - Router with 6DNAC Server, serving both Link1 and Link2
698 <Figure: 7 Example of 6DNAC Server serving multiple links>
701 7.2. 6DNAC Operational Scenarios
703 This section provides message sequence charts for various 6DNAC
704 operational scenarios assuming that the 6DNAC Server is implemented
705 on a router. All the scenarios assume that the normal boot up time
706 stateless address autoconfiguration of Link Local address derived
707 from the Interface Identifier has been completed successfully. And
708 it is also assumed that the router is already configured with the
709 DNS Zone Suffix Information.
714 6DNAC-A, B, C : 6DNAC Clients
715 6DNAC-S : 6DNAC Server/Router
716 DAD : Duplicate Address Detection
717 DFQDND : Duplicate Domain Name Detection
721 7.2.1. Domain Name Registration-Successful Case
723 This scenario starts when a 6DNAC Client receives RA message with
724 DNS Zone Suffix and other parameters including address prefix as
725 specified in NDP [2461] and wants configure its IPv6 address (Global
726 or Site Local) and domain name. It is Assumed that the
727 DupAddrDetectTransmits is set to 1.
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736 +---------+ +---------+ +---------+
737 | 6DNAC-C | | 6DNAC-S | | DNS-S |
738 +----+----+ +----+----+ +----+----+
748 DAD/DFQDND Starts | |
774 <Figure: 8 Domain Name Generation and Registration>
777 #1. 6DNAC Server (Router) sends out router advertisement with DNS
778 Suffix information along with other parameters as specified in
781 #2. 6DNAC Client processes the router advertisement and constructs
782 the FQDN by prefixing hostname to the DNS Zone Suffix. It also
783 constructs IPv6 address from the autoconfiguration prefix
786 #3. 6DNAC Client starts duplicate address & FQDN detection for the
787 IPv6 address & FQDN constructed and sends out a Neighbor
788 Solicitation message with FQDN option.
790 Note that the DAD packets must be addressed to all nodes multicast
791 address if Router Alert option is not used.
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797 #4. 6DNAC Server processes the Neighbor Solicitation message sent by
798 6DNAC Client as part of duplicate FQDN detection procedure and
799 creates a FQDN entry in its FQDN Cache (assuming that there is no
800 entry <FQDN,C>), where C is Link Layer Address of the 6DNAC Client.
802 #5. 6DNAC Server then registers FQDN and corresponding IPv6 address
803 through the existing protocol DDNS UPDATE.
805 #6. 6DNAC Client times out and observes that there is no response to
806 defend its duplicate FQDN detection procedure and the node is
807 successful in configuring its domain name.
809 Note that, Stateless Address Autoconfiguration DAD procedure is not
810 depicted in the following message sequence chart, which simultaneously
811 happens along with duplicate FQDN detection.
814 7.2.2. Domain Name Registration-with DupAddrDetectTransmits=2
816 This scenario starts when a 6DNAC Client receives RA message with
817 DNS Zone Suffix and other parameters including address prefix as
818 specified in NDP [2461] and wants configure its IPv6 address (Global
819 or Site Local) and domain name. The node is configured with
820 DupAddrDetectTransmits = 2 for reliability in delivering DAD messages.
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858 +---------+ +---------+ +---------+
859 | 6DNAC-C | | 6DNAC-S | | DNS-S |
860 +----+----+ +----+----+ +----+----+
870 DAD/DFQDND Starts | |
907 <Figure: 9 Verification of duplicated Domain Name>
910 Steps from #1 to #5 are same as that of scenario.7.2.1.
912 #6. 6DNAC Client sends out second Neighbor Solicitation message with
913 FQDN option as part of duplicate FQDN detection.
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919 #7. 6DNAC Server receives and observes that the FQDN Cache exactly
920 matches with that of the NS information and ignores the NS message.
922 #8. 6DNAC Client times out and observes that there is no response to
923 defend its duplicate FQDN detection procedure and the node is
924 successful in configuring its domain name..
927 7.2.3. Domain Name Registration-Defend Case
929 This scenario starts when two 6DNAC Client receive RA message with
930 DNS Zone Suffix and other parameters including address prefix as
931 specified in NDP [2461] and both the nodes want configure their IPv6
932 address (Global or Site Local) and domain name. In this scenario both
933 the nodes want to have same domain name.
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978 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
982 +---------+ +---------+ +---------+ +---------+
983 | 6DNAC-A | | 6DNAC-S | | 6DNAC-B | | DNS-S |
984 +----+----+ +----+----+ +----+----+ +----+----+
986 | RA with | RA with | |
987 | DNS Suffix Opt | DNS Suffix Opt | |
988 |<---------------|--------------->| |
991 Construct | #2 | Construct | #2 |
994 DAD/DFQDND Starts | DAD/DFQDND Starts |
999 |--------------->| | |
1003 | Create FQDN | #4 | |
1007 | | Register FQDN #5 |
1008 | |-------------------------------->|
1012 | |<---------------| |
1015 | FQDN is in use| | |
1016 | Defend DFQDND| #7 | |
1021 | |--------------->| |
1024 No Response | #9 | Enter | #10 |
1025 DFQDND Success| | Retry Mode| |
1031 <Figure: 10 Multiple Hosts Requesting Same Domain Name>
1037 Park & Madanapalli Expires October 2003 [Page 17]
1039 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1041 #1. 6DNAC Server (Router) sends out router advertisement with DNS
1044 #2. 6DNAC Clients A&B process the router advertisement and construct
1045 their FQDN by prefixing hostname to the DNS Zone Suffix. They
1046 also construct IPv6 address from the autoconfiguration prefix
1049 When each host is trying to go for DAD, all hosts must have
1050 random delay to avoid the traffic congestion according to [2461].
1051 So here it is assumed that 6DNAC Client-A starts DAD first and
1052 6DNAC Client-B starts DAD later.
1054 #3. 6DNAC Client-A starts duplicate address & FQDN detection for the
1055 IPv6 address & FQDN constructed and sends out a Neighbor
1056 Solicitation message with FQDN option.
1058 #4. 6DNAC Server processes the Neighbor Solicitation message sent by
1059 6DNAC Client-A as part of duplicate FQDN detection procedure and
1060 creates a FQDN entry in its FQDN Cache (assuming that there is no
1061 entry <FQDN,A>), where A is Link Layer Address of the 6DNAC Client-A.
1063 #5. 6DNAC Server then registers FQDN and corresponding IPv6 address
1064 through the existing protocol DDNS UPDATE.
1066 #6. 6DNAC Client-B starts duplicate address & FQDN detection for the
1067 IPv6 address & FQDN constructed and sends out a Neighbor Solicitation
1068 message with FQDN option.
1070 #7. 6DNAC Server processes the Neighbor Solicitation message sent by
1071 6DNAC Client-B as part of duplicate FQDN detection procedure and
1072 finds that the domain name is already in use by the 6DNAC Client-A.
1073 Hence, concludes to defend the duplicate FQDN detection of 6DNAC
1076 #8. 6DNAC Server sends out Neighbor Advertisement message with FQDN
1077 option to 6DNAC Client-B to defend its duplicate FQDN detection.
1079 #9. 6DNAC Client-A times out and observes that there is no response to
1080 defend its duplicate FQDN detection procedure and the node is
1081 successful in configuring its domain name.
1083 #10. 6DNAC Client-B observes that there is a NA with FQDN option
1084 indicating that the domain name is duplicate and enters Retry
1085 Mode. In retry mode, 6DNAC Client constructs another FQDN based
1086 on Host Naming Algorithm. The number of retries is defined by the
1087 administrator and must be a configurable value.
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1100 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1102 7.2.4. Domain Name Registration in Retry Mode
1106 1. Duplicate Address Detection has succeeded
1107 2. Duplicate FQDN Detection FAILED
1108 3. FQDN is the first FQDN one constructed and FAILED
1109 4. FQDN2 is the second FQDN to be constructed
1110 5. The Neighbor Solicitation in the 'Retry Mode'
1111 carries unspecified address in its target field (NS*).
1113 +---------+ +---------+ +---------+
1114 | 6DNAC-C | | 6DNAC-S | | DNS-S |
1115 +----+----+ +----+----+ +----+----+
1127 |--------------->| |
1132 | Create FQDN | #3 |
1136 | | Register FQDN2 |
1137 | |--------------->|
1141 No Response | #5 | |
1142 DFQDND-Success | | |
1148 <Figure: 11 Regeneration of Domain Name>
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1163 #1. 6DNAC Client constructs the FQDN again as per Host Naming Algorithm,
1164 the DNS Zone Suffix, and it is FQDN2.
1165 #2. It then starts Duplicate Detection only for Domain Name. 6DNAC
1166 Client sends out NS with FQDN option and unspecified target
1169 #3. 6DNAC Server processes the Retry Mode NS message and finds that
1170 the FQDN2 is not in use and creates Cache entry as <FQDN2, C>.
1172 #4. It then starts registration procedures with the DNS Server.
1174 #5. Meanwhile, 6DNAC Client timesout and observes that there is no
1175 defending NA for its DFQDND NS sent out and successfully
1176 configures its domain name.
1179 7.2.5. Domain Name Registration when DAD Fails
1181 Duplicate domain name detection and subsequent registration starts
1182 if and only if the DAD for IPv6 address succeeds. If the DAD for
1183 IPv6 address fails then no actions are taken for domain name. When
1184 DAD fails for stateless address autoconfiguration, then the domain
1185 configuration starts only when the address has been configured using
1186 Stateful Address Configuration methods and the node is going on DAD
1189 This scenario starts when a 6DNAC Client receives RA message with
1190 DNS Zone Suffix and other parameters including address prefix as
1191 specified in NDP [2461] and wants configure its IPv6 address (Global
1192 or Site Local) and domain name.
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1224 +---------+ +---------+ +---------+ +---------+
1225 | 6DNAC-A | | 6DNAC-S | | 6DNAC-B | | DNS-S |
1226 +----+----+ +----+----+ +----+----+ +----+----+
1230 | DNS Suffix Opt | | |
1231 |<---------------| | |
1238 DAD/DFQDND Starts | | |
1243 |--------------->+--------------->| |
1252 | | My IPv6 Addr| #5 |
1256 |<---------------+<---------------| |
1260 | Delete FQDN | #7 | |
1264 DAD Failed | #8 | | |
1270 <Figure: 12 DAD failure>
1272 #1. 6DNAC Server sends out Router Advertisement to 6DNAC Client-A.
1274 #2. 6DNAC Client-A constructs IPv6 Address based on the prefix and
1275 FQDN as per Host Naming Algorithm.
1277 #3. It then starts Duplicate address & FQDN Detection, for the newly
1278 constructed IPv6 address and FQDN, and sends out DAD/DFQDND NS
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1285 #4. 6DNAC Server processes the DAD/DFQDND NS message and finds
1286 that there is no entry for the FQDN in its cache. And,
1287 creates Cache entry as <FQDN, A> and starts a Registration
1288 timer with RegistrationWaitTime seconds.
1290 #5. 6DNAC Client-B finds that the DAD/DFQDND-NS target address is
1291 in its unicast address list.
1293 #6. It then starts defending DAD by sending NA to all-nodes multicast.
1295 #7. 6DNAC Server finds that the DAD has failed for 6DNAC Client-A.
1296 And, deletes its FQDN Cache entry <FQDN,A>.
1298 #8. 6DNAC Client gets defending DAD-NA and desists from DAD.
1299 And also, stops Duplicate FQDN Detection as well.
1300 At this point the address must be configured using stateful
1301 methods and the domain name registration starts with the DAD
1302 for the newly constructed IPv6 address.
1304 7.3. DNS Zone Suffix Discovery and FQDN Construction
1306 7.3.1. Sending Router Advertisement Messages
1308 Routers send out Router Advertisement message periodically,
1309 or in response to a Router Solicitation. Router should include
1310 the DNS Zone Suffix Option in their advertisements. If the DNS
1311 Zone Suffix changes (similar to Site Renumbering), then it should
1312 advertise the Old Zone Suffix with zero Valid Lifetime and New
1313 Zone Suffix with proper non-zero Valid Lifetime. In any other
1314 case, a router should not send this option twice in a single
1315 router advertisement.
1317 7.3.2. Processing Router Advertisement Messages
1319 For each DNS Zone Suffix Option in Router Advertisement,
1321 a. 6DNAC node stores the Zone Suffix information in its local
1322 database. Also, constructs FQDN as per Host Naming Algorithm.
1324 b. If the node has not configured FQDN yet,
1326 1. If the node is going to perform DAD for either Site local or
1327 Global Address, then it should include FQDN option to perform
1328 Duplicate FQDN Detection in parallel with DAD.
1330 2. If the node has already got either Site local or Global
1331 address, then it should send out NS with FQDN option and
1332 unspecified target address to perform Duplicate FQDN
1335 c. If the node has already configured FQDN, and if the
1336 advertisement carries two DNS Zone Suffix Options,
1337 First DNS Zone Suffix should match with the configured FQDN
1338 Suffix and its Valid Lifetime must be zero. Second DNS Zone
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1347 Suffix should have non-zero Valid Lifetime. In this case, the
1348 node constructs new FQDN based on the new DNS Zone Suffix (from
1349 second DNS Zone Suffix option), and perform Duplicate FQDN
1350 Detection with unspecified target address. Also, it should
1351 overwrite the old FQDN with the newly constructed FQDN.
1354 7.3.3. FQDN Lifetime expiry
1357 It should delete the FQDN cache entry and should de-register from
1361 It should send update to 6DNAC Server by restarting the Duplicate
1364 7.3.4. Host Naming Algorithm
1366 A node constructs FQDN by combining DNS Zone Suffix and the hostname
1367 as depicted in the following diagram.
1369 +------------------+----------------------------------+
1370 | Host Name | Advertised Suffix |
1371 +------------------+----------------------------------+
1373 <Figure 13: Fully Qualified Domain Name format>
1375 A node can choose Host Name using any of the following methods:
1377 a. String form of random number generated from the Interface
1380 b. List of configured Host Names provided by the administrator.
1383 The number of retries must be specified in this algorithm in
1384 case of domain name duplication.
1387 7.4. Duplicate Domain Name Detection
1389 The procedure for detecting duplicated FQDNs uses Neighbor
1390 Solicitation and Advertisement messages as described below.
1392 If a duplicate FQDN is detected during the procedure, the
1393 FQDN cannot be assigned to the node.
1395 An FQDN on which the DFQDND Procedure is applied is said
1396 to be tentative until the procedure has completed successfully.
1397 A tentative FQDN is not considered "assigned to the node" in the
1398 traditional sense. That is, the node must accept Neighbor
1399 Advertisement message containing the tentative FQDN in the FQDN
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1408 It should also be noted that DFQDN must be performed prior to
1409 registering with DNS Server to prevent multiple nodes from using
1410 the same FQDN simultaneously. All the Duplicate Address Detection
1411 Neighbor Solicitation messages must carry Source Link Layer Address
1412 Option as specified in NDP [2461].
1414 The detection of duplicate FQDN can be achieved through one of the
1415 following three types of procedures.
1417 1. DAD with All Nodes Multicast Address
1418 2. DAD with Router Alert Option for 6DNAC.
1419 3. Explicit Detection of Duplicate Domain Name
1421 Even though three solutions are listed, authors prefer only one
1422 procedure to be followed in future based on further analysis and
1423 comments received from others.
1425 7.4.1. DAD with All Nodes Multicast Address
1427 7.4.1.1. Sending Neighbor Solicitation Messages
1429 6DNAC Client sends Neighbor Solicitation Messages as part
1430 of Duplicate Address Detection SLAAC [2462] with the following
1431 extra information and modifications:
1433 a. Include FQDN Option in the DAD Neighbor Solicitation Message
1434 b. Destination Address is set to All Nodes Multicast Address
1436 There may be a case where DAD has succeeded but DFQDND is in Retry
1437 Mode. In such case, the Neighbor Solicitation must carry unspecified
1438 address in the ICMP target address field and new domain name in FQDN
1439 option to re-try the registration of the domain name.
1441 7.4.1.2. Processing Neighbor Solicitation Messages
1443 6DNAC Clients must ignore the FQDN option found in any of the
1444 neighbor solicitation messages.
1446 6DNAC Server processes FQDN Option found in the Duplicate Address
1447 Detection Neighbor Solicitation Messages as described below:
1449 Lookup FQDN Cache for the domain name in FQDN Option.
1451 If the entry exists and
1452 i. Link Layer Address matches with SLLA option, this is the case,
1453 where node has changed its IPv6 address or updating the valid
1454 life time. 6DNAC Server updates its cache and also updates DNS
1455 Server using DDNS-UPDATE. If there is no change in IPv6 address
1456 or life time then no updates are sent to the DNS server.
1458 ii. Link Layer Address differs with SLLA option, defend the duplicate
1459 FQDN Detection by sending Neighbor Advertisement Message as
1460 described in $7.4.1.3$.
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1470 Lookup FQDN Cache for the Link Layer Address in SLLA Option.
1472 If the entry exists, update the FQDN Cache and update DNS Server
1473 using DDNS-UPDATE. This is the case, where node has changed its
1474 domain name (similar to Site Re-numbering).
1476 If then entry does not exists, then it means that this is the new
1477 registration. It must create a cache entry and start Registration
1479 timer with RegistrationWaitTime. At the expiry of the Registration
1480 timer, it should update DNS Server with DDNS-UPDATE.
1482 7.4.1.3. Sending Neighbor Advertisement Messages
1484 6DNAC Server sends Neighbor Advertisement Messages as part
1485 of Duplicate Address Detection SLAAC [2462] with the FQDN Option
1486 in Neighbor Advertisement message to defend duplicate FQDN
1489 There may be the case where defending of duplicate address detection
1490 is not required but defending of FQDN is required. In such instance,
1491 the defending Neighbor Advertisement must carry FQDN and unspecified
1492 address in the ICMP target address field.
1494 7.4.1.4. Processing Neighbor Advertisement Messages
1496 6DNAC Server must ignore the any FQDN option found any of
1497 the neighbor advertisement messages. If the Neighbor Advertisement
1498 is a DAD defending, then it must delete its FQDN Cache entry created
1499 on the reception of DAD Neighbor Solicitation message.
1501 When 6DNAC Clients gets the duplicate address detection neighbor
1502 advertisement messages with FQDN option set it means that its
1503 duplicate FQDN detection failed and enters Retry Mode.
1505 7.4.1.5. Pros and Cons
1507 The advantage of this procedure is that it does not need any
1508 extension header options to be included. The disadvantage of this
1509 procedure is that, it needs change in the existing DAD procedure.
1510 The change is only that the DAD neighbor solicitations are to be
1511 addressed to all nodes multicast address instead of solicited
1512 node multicast address. The another disadvantage is that, it needs
1513 the existence of Duplicate Address Detection Procedure to
1514 perform duplicate FQDN detection.
1516 7.4.2. DAD with Router Alert Option for 6DNAC
1518 7.4.2.1. Sending Neighbor Solicitation Messages
1520 6DNAC Client sends Neighbor Solicitation Messages as part
1521 of Duplicate Address Detection SLAAC [2462] with the following
1525 Park & Madanapalli Expires October 2003 [Page 25]
1527 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1530 a. Include Hop-by-Hop extension Header with Router Alert Option
1531 for 6DNAC as described in IPv6 Router Alert Option[2711].
1533 b. Include FQDN Option in the DAD Neighbor Solicitation Message
1535 7.4.2.2. Processing Neighbor Solicitation Messages
1537 This is same as described in $7.4.1.2$.
1539 7.4.2.3. Sending Neighbor Advertisement Messages
1541 This is same as described in $7.4.1.3$.
1543 7.4.2.4. Processing Neighbor Advertisement Messages
1545 This is same as described in $7.4.1.4$.
1547 7.4.2.5. Pros and Cons
1549 The advantage of this procedure is that it does not disturb
1550 the existing implementation and their way of processing the
1551 packets. The disadvantage is that, it needs the existence
1552 of Duplicate Address Detection Procedure to perform duplicate
1553 FQDN detection. Another disadvantage is that this procedure
1554 requires 6DNAC Server functionality to be implemented on Router.
1555 However, in this case 6DNAC Server can serve multiple links.
1557 7.4.3. Explicit Detection of Duplicate Domain Name
1559 In this procedure Duplicate FQDN Detection starts after completion
1560 of successful Site local or Global Address configuration.
1562 7.4.3.1. Sending Neighbor Solicitation Messages
1564 6DNAC Client sends Neighbor Solicitation Messages as part
1565 of Duplicate FQDN Detection with the following information:
1567 a. Include FQDN Option in the Neighbor Solicitation Message
1569 b. Destination Address is set to All Nodes Multicast Address
1570 or uses Router Alert Option for 6DNAC, when 6DNAC Server is
1571 implemented on router.
1573 c. Target Address is set to Unspecified Address
1575 d. Other fields are set as per DAD SLAAC [2462].
1577 7.4.3.2. Processing Neighbor Solicitation Messages
1579 This is same as described in $7.4.1.2$.
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1591 7.4.3.3. Sending Neighbor Advertisement Messages
1593 This is same as described in $7.4.1.3$.
1595 7.4.3.4. Processing Neighbor Advertisement Messages
1597 This is same as described in $7.4.1.4$.
1599 7.4.3.5. Pros and Cons
1601 The advantage of this procedure is that it does not need the
1602 existing duplicate address detection procedure. This is introduced
1603 as the DAD procedure is found to be redundant in when IPv6 addresses
1604 are constructed from the interface ID [DIID].
1606 Note that, if 6DNAC Clients know the address of 6DNAC Server then
1607 they can directly send DFQDND-NS to 6DNAC Server.
1609 7.4.4. Retry Mode for Re-registering Domain Name
1611 In retry mode, nodes construct new FQDN as per Host Naming Algorithm.
1612 Then they restart Duplicate FQDN Detection as described in $7.4.3$.
1615 7.5. Domain Name Registration
1617 6DNAC Server must be an authenticated to update the DNS Server.
1618 6DNAC Server must also be configured with the DNS Server
1621 6DNAC Server detects the DNS information (IPv6 Address and
1622 corresponding FQDN) from DAD/DFQDND messages and caches the
1623 information. It also have an associated Registration Timer with
1624 RegistrationWaitTime to wait for the successful completion of
1625 DFQDND and update DNS Server using existing protocol DDNS UPDATE
1629 8. Security Consideration
1631 If someone wants to hijack correct Domain Name registration, they
1632 could send a NS message with incorrect or same Domain Name to the
1633 6DNAC server repeatedly and server would start the Domain Name
1634 registration through above mechanism, which is a security hole.
1635 As described in [2461], a host can check validity of NDP messages.
1636 If the NDP message include an IP Authentication Header, the message
1637 authenticates correctly. For DNS UPDATE processing, secure DNS
1638 Dynamic Update is described in [3007].
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1649 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1652 9. IANA Consideration
1654 Values in the Router Alert Option are registered and maintained by
1655 IANA. For 6DNAC, the value has to be assigned by IANA. Also IANA is
1656 required to assign the Type values for DNS Zone Suffix Information
1657 option and FADN option.
1662 Special thanks are due to Badrinarayana N.S. and Christian Huitema for
1663 many helpful suggestions and revisions.
1666 11. Intellectual Property
1668 The following notice is copied from RFC 2026 [Bradner, 1996],
1669 Section 10.4, and describes the position of the IETF concerning
1670 intellectual property claims made against this document.
1672 The IETF takes no position regarding the validity or scope of any
1673 intellectual property or other rights that might be claimed to
1674 pertain to the implementation or use other technology described in
1676 this document or the extent to which any license under such rights
1677 might or might not be available; neither does it represent that it
1679 has made any effort to identify any such rights. Information on the
1680 IETF's procedures with respect to rights in standards-track and
1681 standards-related documentation can be found in BCP-11. Copies of
1682 claims of rights made available for publication and any assurances
1683 of licenses to be made available, or the result of an attempt made
1684 to obtain a general license or permission for the use of such
1685 proprietary rights by implementers or users of this specification
1686 can be obtained from the IETF Secretariat.
1688 The IETF invites any interested party to bring to its attention any
1689 copyrights, patents or patent applications, or other proprietary
1690 rights which may cover technology that may be required to practice
1691 this standard. Please address the information to the IETF Executive
1697 The following copyright notice is copied from RFC 2026 [Bradner,
1698 1996], Section 10.4, and describes the applicable copyright for this
1701 Copyright (C) The Internet Society July 12, 2001. All Rights
1704 This document and translations of it may be copied and furnished to
1705 others, and derivative works that comment on or otherwise explain it
1706 or assist in its implementation may be prepared, copied, published
1708 Park & Madanapalli Expires October 2003 [Page 28]
1710 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1713 and distributed, in whole or in part, without restriction of any
1714 kind, provided that the above copyright notice and this paragraph
1715 are included on all such copies and derivative works. However, this
1717 document itself may not be modified in any way, such as by removing
1718 the copyright notice or references to the Internet Society or other
1719 Internet organizations, except as needed for the purpose of
1720 developing Internet standards in which case the procedures for
1721 copyrights defined in the Internet Standards process must be
1722 followed, or as required to translate it into languages other than
1725 The limited permissions granted above are perpetual and will not be
1726 revoked by the Internet Society or its successors or assignees.
1728 This document and the information contained herein is provided on an
1729 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
1730 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
1731 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
1732 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
1733 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
1738 [2373] Hinden, R. and S. Deering, "IP Version 6 Addressing
1739 Architecture", RFC 2373, July 1998.
1741 [2460] Deering, S. abd R. Hinden, "Internet Protocol,
1742 Version 6 (IPv6) Specification", RFC 2460,
1745 [2461] Narten, T., Nordmark, E. and W. Simpson, "Neighbor
1746 Discovery for IP version 6(IPv6)", RFC 2461, December
1749 [2462] S. Thomson and Narten T, "IPv6 Stateless Address Auto-
1750 Configuration", RFC 2462, December 1998.
1752 [2711] C. Patridge and A.Jackson, "IPv6 Router Alert Option",
1753 RFC 2711, October 1999.
1755 [1034] P. Mockapetris, "DOMAIN NAMES - CONCEPTS AND
1756 FACILITIES", RFC 1034, November 1987.
1758 [1035] P. Mockapetris, "Domain Names - Implementation and
1759 Specification" RFC 1035, November 1987.
1761 [2136] P. Vixie et al., "Dynamic Updates in the Domain Name
1762 System (DNS UPDATE)", RFC2136, April 1997.
1764 [3007] B. Wellington, "Secure Domain Name System (DNS) Dynamic
1765 Update", RFC 3007, November 2000.
1769 Park & Madanapalli Expires October 2003 [Page 29]
1771 INTERNET-DRAFT IPv6 Extensions for DNS Plug and Play April 2003
1774 [DIID] yokohama-dad-vs-diid.pdf
1775 at http://playground.sun.com/ipng/presentations/July2002/
1777 [DNSISSUES] Durand, A., "IPv6 DNS transition issues", draft-ietf-
1778 dnsop-ipv6-dns-issues-00.txt, work in progress.
1780 [PREFIX] S. Miyakawa, R. Droms, "Requirements for IPv6 prefix
1781 delegation", draft-ietf-ipv6-prefix-delegation-
1782 requirement-01.txt, work in progress.
1784 [Autoreg] H. Kitamura, "Domain Name Auto-Registration for
1785 Plugged-in IPv6 Nodes", draft-ietf-dnsext-ipv6-name-
1786 auto-reg-00.txt, work in progress.
1788 [NIQ] Matt Crawford, "IPv6 Node Information Queries", <draft-
1789 ietf-ipngwg-icmp-name-lookups-09.txt>, work in progress.
1792 14. Author's Addresses
1795 Mobile Platform Laboratory, SAMSUNG Electronics, KOREA
1796 Phone: +82-31-200-3728
1797 Email:soohong.park@samsung.com
1800 Network Systems Division, SAMSUNG India Software Operations, INDIA
1801 Phone: +91-80-5550555
1802 Email:syam@samsung.com
1830 Park & Madanapalli Expires October 2003 [Page 30]