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freebsd-dev/contrib/bind9/doc/draft/draft-park-ipv6-extensions-dns-pnp-00.txt
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INTERNET-DRAFT S. Daniel Park
Expires: October 2003 Syam Madanapalli
File: SAMSUNG Electronics
draft-park-ipv6-extensions-dns-pnp-00.txt April 2003
IPv6 Extensions for DNS Plug and Play
Status of This Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as
Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other
documents at any time. It is inappropriate to use Internet-Drafts
as reference material or to cite them other than as "work in
progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Abstract
This document proposes automatic configuration of domain name (FQDN)
for IPv6 nodes using Domain Name Auto-Configuration (called 6DNAC) as
a part of IPv6 plug and play feature. 6DNAC allows the automatic
registration of domain name and corresponding IPv6 Addresses with
the DNS server. In order to provide 6DNAC function, Neighbor Discovery
Protocol [2461] will be used. Moreover, 6DNAC does not require any
changes to the existing DNS system.
Table of Contents
1. Introduction ............................................. 3
2. Terminology .............................................. 3
3. 6DNAC Design Principles .................................. 4
4. 6DNAC Overview ........................................... 4
5. 6DNAC Requirements ....................................... 5
5.1. 6DANR Client Requirements ................................ 5
5.2. 6DNAC Server Requirements ................................ 6
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6. 6DNAC Messages and Option Formats ........................ 6
6.1. Router Advertisement (RA) Message Format ................. 6
6.2. Neighbor Solicitation (NS) Message Format ................ 7
6.3. Neighbor Advertisement (NA) Message Format ............... 8
6.4. Option Formats ........................................... 8
6.4.1. DNS Zone Suffix Information Option Format ................ 8
6.4.2. Domain Name (FQDN) Option Format ......................... 9
6.4.3. Router Alert Option for 6DNAC ............................ 10
7. 6DNAC Operation .......................................... 10
7.1. 6DNAC Network Topology ................................... 11
7.2. 6DNAC Operational Scenarios .............................. 12
7.2.1. Domain Name Registration-Success Case .................... 12
7.2.2. Domain Name Registration-with DupAddrDetectTransmits=2.... 14
7.2.3. Domain Name Registration-Defend Case ..................... 16
7.2.4. Domain Name Registration in Retry Mode ................... 19
7.2.5. Domain Name Registration when DAD Fails .................. 20
7.3. DNS Zone Suffix Discovery and FQDN Construction .......... 22
7.3.1. Sending Router Advertisement Messages .................... 22
7.3.2. Processing Router Advertisement Messages ................. 22
7.3.3. FQDN Lifetime expiry ..................................... 23
7.3.4. Host Naming Algorithm .................................... 23
7.4. Duplicate Domain Name Detection .......................... 23
7.4.1. DAD with All Nodes Multicast Address ..................... 24
7.4.1.1. Sending Neighbor Solicitation Messages ................... 24
7.4.1.2. Processing Neighbor Solicitation Messages ................ 24
7.4.1.3. Sending Neighbor Advertisement Messages .................. 25
7.4.1.4. Processing Neighbor Advertisement Messages ............... 25
7.4.1.5. Pros and Cons ............................................ 25
7.4.2. DAD with Router Alert Option for 6DNAC ................... 25
7.4.2.1. Sending Neighbor Solicitation Messages ................... 25
7.4.2.2. Processing Neighbor Solicitation Messages ................ 26
7.4.2.3. Sending Neighbor Advertisement Messages .................. 26
7.4.2.4. Processing Neighbor Advertisement Messages ............... 26
7.4.2.5. Pros and Cons ............................................ 26
7.4.3. Explicit Detection of Duplicate Domain Name .............. 26
7.4.3.1. Sending Neighbor Solicitation Messages ................... 26
7.4.3.2. Processing Neighbor Solicitation Messages ................ 26
7.4.3.3. Sending Neighbor Advertisement Messages .................. 27
7.4.3.4. Processing Neighbor Advertisement Messages ............... 27
7.4.3.5. Pros and Cons ............................................ 27
7.4.4. Retry Mode for Re-registering Domain Name ................ 27
7.5. Domain Name Registration ................................. 27
8. Security Consideration ................................... 27
9. IANA Consideration ....................................... 28
10. Acknowledgement .......................................... 28
11. Intellectual Property .................................... 28
12. Copyright ................................................ 28
13. References ............................................... 29
14. Author's Addresses ....................................... 30
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1. Introduction
Today, most networks use DNS[1034][1035] for convenience. In case of
IPv6, DNS is more important element because of IPv6 long addresses
which are difficult to remember. In addition, small networks like home
networks using IPv6, should be able to make network easily without
manual configuration. Also, these small networks may not have DHCP
Server, DNS Server etc. that are used to configure the network. This
document discusses IPv6 Domain Name Auto-Configuration(6DNAC) procedure
for generating and registering the Domain Name and IPv6 addresses with
the DNS Server automatically. In order to use 6DNAC, IPv6 nodes are
required to implement lightweight functions specified in this document.
6DNAC can be applied to all defined IPv6 unicast addresses except Link
local IPv6 addresses, viz: Site-local and Global addresses.
6DNAC uses Neighbor Discovery Protocol [2461] with new additions
(defined in section 6) and DAD procedures for generating and
registering the Domain Name with the DNS server automatically.
2. Terminology
6DNAC - IPv6 Domain Name Auto Configuration. It can provide
IPv6 hosts with Domain Name Generation and
Registration automatically.
6DNAC Client - An IPv6 node that can generate its own unique Domain
Name. Section 3 identifies the new requirements that
6DNAC places on an IPv6 node to be a 6DNAC node.
6DNAC Server - An IPv6 node that can collect and registrate Domain
Name and IPv6 addresses automatically. 6DNAC server
uses the information from the DAD operation messages
with newly defined options for the registration of the
Domain Name and IPv6 Addresses. Section 3 identifies
the new requirements that 6DNAC places on an IPv6
node to be a 6DNAC server. Also 6DNAC server can have
various other functions depending on network
environment and the network operator. For instance
6DNAC Server can acts as a Gateway as well Home Server
in Home Networks.
DAD - Duplicate Address Detection (is defined [2461])
DFQDND - Duplicate Domain Name Detection
FQDN - Fully Qualified Domain Name - FQDN and Domain Name are
used interchangeably in this document.
NA - Neighbor Advertisement message (is defined [2461])
NS - Neighbor Solicitation message (is defined [2461])
RA - Router Advertisement message (is defined [2461])
SLAAC - Stateless Address Autoconfiguration [2462].
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3. 6DNAC Design Principles
This section discusses the design principles of 6DNAC mechanism.
1. The new procedures for plug and play DNS should not cause changes
to existing DNS system. 6DNAC requires lightweight functions to be
implemented only at the client side of the DNS system, and uses the
existing DDNS UPDATE [2136] to communicate with DNS Servers.
2. Introducing a new protocol will always introduce new problems.
6DNAC uses the existing protocols NDP [2461] with minor extensions
for generating and registering the domain name automatically
without defining a new protocol
3. Reusing proven and well understood design principles/patterns
will always yield a robust system. 6DNAC is based on IPv6 Address
Auotoconfiguration principle, where routers advertise the prefix
and host adds the interface ID to the prefix and forms the IPv6
address. Domain Name (FQDN) also contains two parts: host name
and DNS zone suffix. Routers can advertise the DNS zone suffix
on a particular link in Router Advertisements (RA Messages) and
hosts can prefix their preferred host name to the DNS zone suffix
and form the fully qualified domain name. Also the detection of
duplicate domain name is similar to Duplicate Address Detection
(DAD) and can be part of DAD operation itself.
4. 6DNAC Overview
6DNAC proposes minor extensions to NDP [2461] for automatic generation
and registration of domain name with the DNS server. It introduces two
new options: DNS Zone Suffix and Fully Qualified Domain Name. DNS Zone
Suffix option is carried in Router Advertisement (RA) messages for
notifying IPv6 nodes about the valid DNS Zone Suffix on the link and
FQDN option in Neighbor Solicitation (NS) and Neighbor Advertisement
(NA) messages to detect duplicate domain name. 6DNAC consists of two
components: 6DNAC Client and 6DNAC Server. 6DNAC Clients generate the
domain name based on DNS Zone Suffix using Host Naming Algorithm (see
section 7.3.1) and 6DNAC Server collects and registers the DNS
information with the DNS Server on behalf of 6DNAC Clients.
The automatic configuration of domain name using 6DNAC consists of
three parts.
- DNS Zone Suffix Discovery and FQDN Construction:
IPv6 Nodes collect DNS Zone Suffix information from Router
Advertisements and constructs FQDN by prefixing host name to the
DNS Zone Suffix. The IPv6 Nodes are required to implement Host
Naming Algorithm for generating host part of the FQDN in the
absence of administrator.
Generation of node's FQDN within the node itself has advantages. Nodes
can provide forward and reverse name lookups independent of the DNS
System by sending queries directly to IPv6 nodes [NIQ]. Moreover Domain
Name is some thing that is owned by the node.
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- Duplicate Domain Name Detection
All nodes are expected to go for DAD for all new IPv6 unicast
addresses, regardless of whether they are obtained through
stateful, stateless or manual configuration. 6DNAC uses the DAD
messages with new option for carrying the Domain Name along with
the new IPv6 Address. 6DNAC Server captures this information and
updates DNS Server provided that the IPv6 Address and its domain
name are not duplicate. If the domain name is already in use,
the 6DNAC server replies to the sender with FQDN Option in NA
message indicating that the domain name is duplicate. Then the
node is expected to generate another domain name using host
naming algorithm and go for DAD. This time the DAD is only for
duplicate domain name detection (DFQDND). In order to avoid
confusion with the normal NDP processing, the target address
field of the NS message must carry the unspecified address
in retry mode. This can be repeated depending on number of
retries defined by the administrator in the host naming algorithm.
- Domain Name Registration
6DNAC Server detects the DNS information (IPv6 Address and
corresponding FQDN) from DAD/DFQDND messages and updates DNS
Server using existing protocol DDNS UPDATE [2136] provided that
the IPv6 Address and its domain name are not duplicate.
If an IPv6 Address is duplicate, the IPv6 node cannot perform
stateless address autoconfiguration repeatedly. Unlike IPv6 stateless
address autoconfiguration, 6DNAC allows the automatic configuration of
domain name repeatedly if the domain name is duplicate depending on
number of retries defined by the administrator in the host naming
algorithm.
5. 6DNAC Requirements
Depending on the 6DNAC functionality, the IPv6 nodes implement, they
are called either 6DNAC Clients or 6DNAC Servers. The following
sections lists the requirements that the 6DNAC Client and 6DNAC server
must support.
5.1. 6DANC Client Requirements
- 6DNAC Client must recognize and process the following NDP
extensions
- DNS Zone Suffix option in RA messages for generating its
domain name (FQDN).
- Domain Name option in NS and NA messages for detecting
the duplicate domain name
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- It must generate its domain name (FQDN) based on the DNS
suffix that it got from the router advertisement. And it must
have a host naming algorithm for generating the host part of
the FQDN.
- If NA message is received with unspecified target address and
FQDN option, then the node must treat that the domain is
duplicate.
5.2. 6DNAC Server Requirements
- 6DNAC Server must recognize and process the following NDP
extensions
- If the 6DNAC Server is a router on the link, then it
must advertise DNS Zone Suffix option in RA messages
for hosts to generate their domain name (FQDN).
- FQDN option in NS messages for detecting new DNS
information for of nodes on the link for which it
must update the AAAA RR and PTR RR in DNS Server.
- FQDN option in NA messages for notifying duplicate
domain name with unspecified target address.
- 6DNAC server must update the DNS Server (both AAAA RR and
PTR RR) dynamically using DDNS UPDATE [2136].
- 6DNAC server must cache this (newly detected) FQDN, Link
Layer Address, and IPv6 Address information, so that it can
decide whether it really needs to update DNS Server or not,
to avoid redundant updates. This information will also be
used for notifying the duplicate domain name.
6. 6DNAC Messages and Option Formats
In order to achieve the plug and play DNS, 6DNAC proposes new
extensions to the NDP [2461]. This section specifies the new
additions to NDP messages and formats of new options.
6.1. Router Advertisement (RA) Message Format
Routers send out Router Advertisement (RA) message periodically, or
in response to a Router Solicitation. 6DNAC does not modify the format
of the RA message, but proposes new option (DNS Zone Suffix Information)
to be carried in RA messages.
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0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Cur Hop Limit |M|O| Reserved | Router Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reachable Time |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Retrans Timer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ... |
/ /
| DNS Zone Suffix Information |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
<Figure: 1 RA message>
6.2. Neighbor Solicitation (NS) Message Format
6DNAC does not modify the format of the Neighbor Solicitation (NS)
message, but proposes new option (FQDN Option) to be carried in NS
messages. When a node is going for DAD, the node must include FQDN
option in NS message to participate in plug and play DNS. If the
node is going for Explicit Detection of Duplicate Domain Name, the
node must use FQDN option in NS message and unspecified address in
the target address field.
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Target Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ... |
/ /
| Domain Name |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
<Figure: 2 NS message>
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6.3. Neighbor Advertisement (NA) Message Format
6DNAC does not modify the format of the Neighbor Advertisement (NA)
message, but proposes new option (FQDN Option) to be carried in NA
messages. 6DNAC Server sends NA message with FQDN option to 6DNAC
Client that is performing duplicate domain name detection in case
the domain name found to be duplicate.
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|R|S|O| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Target Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Options ... |
/ /
| FQDN Option |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
<Figure: 3 NA message>
6.4 Option Formats
6.4.1. DNS Zone Suffix Information Option Format
IPv6 nodes require DNS Zone Suffix for constructing their FQDN.
6DNAC introduces new option for routers to advertise the DNS Zone
Suffix Information for IPv6 nodes on the link. The suffix information
should be configured into routers manually.
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Valid Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
/ DNS Zone Suffix /
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
<Figure: 4 DNS Zone Suffix Information>
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Type [TBD]
Length 8-bit unsigned integer. The length of the option
(including the type and length fields) in units of
8 octets.
Reserved This field is unused. It must be initialized to zero
by the sender and must be ignored by the receiver.
Valid Life Time 32-bit signed integer. The maximum time, in
seconds, over which this suffix is valid. Nodes
should treat this as the life time for their domain
name. Nodes should contact the source of this
information before expiry of this time interval.
A value of all one bits (0xFFFFFFFF) represents
infinity.
DNS Zone Suffix The suffix part of the FQDN. The data in the DNS
Zone Suffix field should be encoded according to
DNS encoding rules specified in [1035].
6.4.2. Domain Name (FQDN) Option Format
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Valid Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ FQDN Target Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
/ Domain Name /
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
<Figure: 5 FQDN Information>
Type [TBD]
Length 8-bit unsigned integer. The length of the option
(including the type and length fields) in units
of 8 octets. It must be greater than 3.
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Reserved This field is unused. It must be initialized to
zero by the sender and must be ignored by the
receiver.
Valid Life Time 32-bit signed integer. The maximum time, in
seconds, over which this domain name is valid
6DNAC should deregister this domain name at
the expiry of this interval. 6DNAC clients
should send updates by the expiry of this
interval. A value of all one bits (0xFFFFFFFF)
represents infinity.
FQDN Target Address The Address for which the FQDN maps to. It
should be same as Target Address field of the
NS message in case of DAD & duplicate FQDN are
running in parallel.
Domain Name The domain name (FQDN) of the node. The data in
the domain name should be encoded according to
DNS encoding rules specified in [1035].
6.4.3. Router Alert Option for 6DNAC
Router Alert Option for 6DNAC is new option within the IPv6 Hop-by-Hop
Header for using in NDP messages. The presence of this option in NS
message informs the router that this NS message is carrying Domain
Name information and must be processed by the 6DNAC Server on the router.
6DNAC Clients can use this option for sending DAD packets instead
of addressing the DAD packets to the all-nodes multicast address
when 6DNAC Server is implemented on router.
The Router Alert option has the following format:
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0|0 0 1 0 1|0 0 0 0 0 0 1 0| Value (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Length = 2
Values are registered and maintained by the IANA. For 6DNAC, the
value has to be assigned by IANA.
Further information about this option can be obtained from
IPv6 Router Alert Option [2711].
7. 6DNAC Operation
6DNAC provides mechanisms for automatic generation of domain name
and registering it with the DNS Server for IPv6 nodes. 6DNAC consists
of two components: 6DNAC Client and 6DNAC Server. All nodes that want
to participate in plug and play DNS are required to implement 6DNAC
Client functionality, and one of the IPv6 nodes is required to
implement 6DNAC Server functionality. The IPv6 node that implements
the 6DNAC Server functionality must know the location of the DNS
Server and must be a trusted node to send DDNS UPDATE [2136] messages.
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7.1. 6DNAC Network Topology
This section identifies the possible locations for the 6DNAC Server.
Note that, all nodes are required to implement 6DNAC Client
functionality for constructing the domain name from the DNS Zone
Suffix Information advertised by the router. Figure 6 illustrates
IPv6 host (H4) implementing 6DNAC Server functionality. In this case
H4 can serve only one link (that it belongs to) for automatic
registration of domain name. H4 must observe the DAD packets on the
link to detect the DNS information, this requires all nodes on the
link must belong to same solicited node multicast address. In general,
this may not be the case. So the node that is going for DAD must use
all nodes multicast address for DAD packets, so that the 6DNAC Server
(H4) can observe the DAD packets, detects IPv6 address and
corresponding domain name, checks if this domain name is duplicate
and finally registers the domain name with the DNS Server.
6DNAC Server
+---+ +---+ +----------+
| H1| | H4|<--- DDNS UPDATE --->|DNS Server|
+-+-+ +-+-+ +----+-----+
| | +----+ +---/
| | | | /
---+-----+-----------+-----+-----------+ R1 +-----+
| | | |
| | +----+
+-+-+ +-+-+
| H2| | H3|
+---+ +---+
H1, H2, H3 - 6DNAC Clients
H4 - 6DNAC Server
R1 - Router
<Figure: 6 Example of 6DNAC Topology>
Figure 7 shows the 6DNAC Server implemented on a router R1. In this
case a single 6DNAC server can serve multiple links for automatic
configuration of the domain name. This topology also has flexibility
of using DAD packets with Router Alert option instead of sending DAD
packets to all nodes multicast address. The routers are required to
process all the packets with Router Alert option as per [2711].
In case of Home Networks, R1 is will acts as a Home Gateway (CPE)
connected to ISP. R1 delegates the prefix from the ISP edge router.
After delegating the prefix the CPE can advertise the DNS Zone suffix
along with the prefix information to the nodes on the links to which
the router is connected to. Note that the R1 must be configured with
the DNS Zone suffix Information manually.
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+---+ +---+
| H3+ | H4|
+-+-+ +-+-+
| |
| LINK2 |
+---+ ---+--------+--+-- +----------+
| H1| | |DNS Server|
+-+-+ | +----+-----+
| +--+-+ -------/
| LINK 1 | | /
---+-----+------------------+ R1 +---------+
| | | DDNS UPDATE
| +----+
+-+-+ 6DNAC Server
| H2|
+---+
H1, H2 - 6DNAC Clients on Link1
H3, H4 - 6DNAC Clients on Link2
R1 - Router with 6DNAC Server, serving both Link1 and Link2
<Figure: 7 Example of 6DNAC Server serving multiple links>
7.2. 6DNAC Operational Scenarios
This section provides message sequence charts for various 6DNAC
operational scenarios assuming that the 6DNAC Server is implemented
on a router. All the scenarios assume that the normal boot up time
stateless address autoconfiguration of Link Local address derived
from the Interface Identifier has been completed successfully. And
it is also assumed that the router is already configured with the
DNS Zone Suffix Information.
Legend:
6DNAC-A, B, C : 6DNAC Clients
6DNAC-S : 6DNAC Server/Router
DAD : Duplicate Address Detection
DFQDND : Duplicate Domain Name Detection
DNS-S : DNS Server
7.2.1. Domain Name Registration-Successful Case
This scenario starts when a 6DNAC Client receives RA message with
DNS Zone Suffix and other parameters including address prefix as
specified in NDP [2461] and wants configure its IPv6 address (Global
or Site Local) and domain name. It is Assumed that the
DupAddrDetectTransmits is set to 1.
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+---------+ +---------+ +---------+
| 6DNAC-C | | 6DNAC-S | | DNS-S |
+----+----+ +----+----+ +----+----+
| | |
| RA with | |
| DNS Suffix Opt | |
|<---------------| |
| #1 | |
|---+ | |
Construct |#2 | |
FQDN | | |
|<--+ | |
DAD/DFQDND Starts | |
| | |
| | |
| NS With | |
| FQDN Opt | |
|--------------->| |
| #3 | |
| | |
| |------+ |
| Create FQDN | #4 |
| <FQDN,C> | |
| |<-----+ |
| | |
| | Register FQDN |
| |--------------->|
| | #5 |
| #6 | |
|--------+ | |
No Response | | |
DFQDND-Success | | |
|<-------+ | |
| | |
| | |
v V v
<Figure: 8 Domain Name Generation and Registration>
#1. 6DNAC Server (Router) sends out router advertisement with DNS
Suffix information along with other parameters as specified in
NDP [2461].
#2. 6DNAC Client processes the router advertisement and constructs
the FQDN by prefixing hostname to the DNS Zone Suffix. It also
constructs IPv6 address from the autoconfiguration prefix
information option.
#3. 6DNAC Client starts duplicate address & FQDN detection for the
IPv6 address & FQDN constructed and sends out a Neighbor
Solicitation message with FQDN option.
Note that the DAD packets must be addressed to all nodes multicast
address if Router Alert option is not used.
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#4. 6DNAC Server processes the Neighbor Solicitation message sent by
6DNAC Client as part of duplicate FQDN detection procedure and
creates a FQDN entry in its FQDN Cache (assuming that there is no
entry <FQDN,C>), where C is Link Layer Address of the 6DNAC Client.
#5. 6DNAC Server then registers FQDN and corresponding IPv6 address
through the existing protocol DDNS UPDATE.
#6. 6DNAC Client times out and observes that there is no response to
defend its duplicate FQDN detection procedure and the node is
successful in configuring its domain name.
Note that, Stateless Address Autoconfiguration DAD procedure is not
depicted in the following message sequence chart, which simultaneously
happens along with duplicate FQDN detection.
7.2.2. Domain Name Registration-with DupAddrDetectTransmits=2
This scenario starts when a 6DNAC Client receives RA message with
DNS Zone Suffix and other parameters including address prefix as
specified in NDP [2461] and wants configure its IPv6 address (Global
or Site Local) and domain name. The node is configured with
DupAddrDetectTransmits = 2 for reliability in delivering DAD messages.
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+---------+ +---------+ +---------+
| 6DNAC-C | | 6DNAC-S | | DNS-S |
+----+----+ +----+----+ +----+----+
| | |
| RA with | |
| DNS Suffix Opt | |
|<---------------| |
| #1 | |
|---+ | |
Construct |#2 | |
FQDN | | |
|<--+ | |
DAD/DFQDND Starts | |
| | |
| | |
| NS With | |
| FQDN Opt | |
|--------------->| |
| #3 | |
| | |
| |------+ |
| Create FQDN | #4 |
| <FQDN,C> | |
| |<-----+ |
| | |
| | Register FQDN |
| |--------------->|
| | #5 |
| NS With | |
| FQDN Opt | |
|--------------->| |
| #6 | |
| | |
| Lookup FQDN |
| Entry exists |
| |------+ |
| Ignore | #7 |
| |<-----+ |
| #8 | |
|--------+ | |
No Response | | |
DFQDND-Success | | |
|<-------+ | |
| | |
| | |
v V v
<Figure: 9 Verification of duplicated Domain Name>
Steps from #1 to #5 are same as that of scenario.7.2.1.
#6. 6DNAC Client sends out second Neighbor Solicitation message with
FQDN option as part of duplicate FQDN detection.
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#7. 6DNAC Server receives and observes that the FQDN Cache exactly
matches with that of the NS information and ignores the NS message.
#8. 6DNAC Client times out and observes that there is no response to
defend its duplicate FQDN detection procedure and the node is
successful in configuring its domain name..
7.2.3. Domain Name Registration-Defend Case
This scenario starts when two 6DNAC Client receive RA message with
DNS Zone Suffix and other parameters including address prefix as
specified in NDP [2461] and both the nodes want configure their IPv6
address (Global or Site Local) and domain name. In this scenario both
the nodes want to have same domain name.
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+---------+ +---------+ +---------+ +---------+
| 6DNAC-A | | 6DNAC-S | | 6DNAC-B | | DNS-S |
+----+----+ +----+----+ +----+----+ +----+----+
| | | |
| RA with | RA with | |
| DNS Suffix Opt | DNS Suffix Opt | |
|<---------------|--------------->| |
| #1 | #1 | |
|---+ | |---+ |
Construct | #2 | Construct | #2 |
FQDN | | FQDN | |
|<--+ | |<--+ |
DAD/DFQDND Starts | DAD/DFQDND Starts |
| | <DELAYED> |
| | | |
| NS with | | |
| FQDN Opt | | |
|--------------->| | |
| #3 | | |
| No Entry | |
| |------+ | |
| Create FQDN | #4 | |
| <FQDN,A> | | |
| |<-----+ | |
| | | |
| | Register FQDN #5 |
| |-------------------------------->|
| | | |
| | NS with | |
| | FQDN Opt | |
| |<---------------| |
| | #6 | |
| |------+ | |
| FQDN is in use| | |
| Defend DFQDND| #7 | |
| |<-----+ | |
| | | |
| | NA with | |
| | D-flag Set | |
| |--------------->| |
| | #8 | |
|------+ | |---+ |
No Response | #9 | Enter | #10 |
DFQDND Success| | Retry Mode| |
|<-----+ | |<--+ |
| | | |
v v v v
<Figure: 10 Multiple Hosts Requesting Same Domain Name>
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#1. 6DNAC Server (Router) sends out router advertisement with DNS
Suffix information.
#2. 6DNAC Clients A&B process the router advertisement and construct
their FQDN by prefixing hostname to the DNS Zone Suffix. They
also construct IPv6 address from the autoconfiguration prefix
information option.
When each host is trying to go for DAD, all hosts must have
random delay to avoid the traffic congestion according to [2461].
So here it is assumed that 6DNAC Client-A starts DAD first and
6DNAC Client-B starts DAD later.
#3. 6DNAC Client-A starts duplicate address & FQDN detection for the
IPv6 address & FQDN constructed and sends out a Neighbor
Solicitation message with FQDN option.
#4. 6DNAC Server processes the Neighbor Solicitation message sent by
6DNAC Client-A as part of duplicate FQDN detection procedure and
creates a FQDN entry in its FQDN Cache (assuming that there is no
entry <FQDN,A>), where A is Link Layer Address of the 6DNAC Client-A.
#5. 6DNAC Server then registers FQDN and corresponding IPv6 address
through the existing protocol DDNS UPDATE.
#6. 6DNAC Client-B starts duplicate address & FQDN detection for the
IPv6 address & FQDN constructed and sends out a Neighbor Solicitation
message with FQDN option.
#7. 6DNAC Server processes the Neighbor Solicitation message sent by
6DNAC Client-B as part of duplicate FQDN detection procedure and
finds that the domain name is already in use by the 6DNAC Client-A.
Hence, concludes to defend the duplicate FQDN detection of 6DNAC
Client-B.
#8. 6DNAC Server sends out Neighbor Advertisement message with FQDN
option to 6DNAC Client-B to defend its duplicate FQDN detection.
#9. 6DNAC Client-A times out and observes that there is no response to
defend its duplicate FQDN detection procedure and the node is
successful in configuring its domain name.
#10. 6DNAC Client-B observes that there is a NA with FQDN option
indicating that the domain name is duplicate and enters Retry
Mode. In retry mode, 6DNAC Client constructs another FQDN based
on Host Naming Algorithm. The number of retries is defined by the
administrator and must be a configurable value.
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7.2.4. Domain Name Registration in Retry Mode
Pre-Conditions:
1. Duplicate Address Detection has succeeded
2. Duplicate FQDN Detection FAILED
3. FQDN is the first FQDN one constructed and FAILED
4. FQDN2 is the second FQDN to be constructed
5. The Neighbor Solicitation in the 'Retry Mode'
carries unspecified address in its target field (NS*).
+---------+ +---------+ +---------+
| 6DNAC-C | | 6DNAC-S | | DNS-S |
+----+----+ +----+----+ +----+----+
| | |
|--------+ | |
Construct | #1 | |
new FQDN2 | | |
|<-------+ | |
| | |
DFQDND Restarts | |
| | |
| | |
| NS* With | |
| FQDN Opt | |
|--------------->| |
| #2 | |
| | |
| No Entry |
| |------+ |
| Create FQDN | #3 |
| <FQDN2,C> | |
| |<-----+ |
| | |
| | Register FQDN2 |
| |--------------->|
| | #4 |
| | |
|--------+ | |
No Response | #5 | |
DFQDND-Success | | |
|<-------+ | |
| | |
v V v
<Figure: 11 Regeneration of Domain Name>
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#1. 6DNAC Client constructs the FQDN again as per Host Naming Algorithm,
the DNS Zone Suffix, and it is FQDN2.
#2. It then starts Duplicate Detection only for Domain Name. 6DNAC
Client sends out NS with FQDN option and unspecified target
address.
#3. 6DNAC Server processes the Retry Mode NS message and finds that
the FQDN2 is not in use and creates Cache entry as <FQDN2, C>.
#4. It then starts registration procedures with the DNS Server.
#5. Meanwhile, 6DNAC Client timesout and observes that there is no
defending NA for its DFQDND NS sent out and successfully
configures its domain name.
7.2.5. Domain Name Registration when DAD Fails
Duplicate domain name detection and subsequent registration starts
if and only if the DAD for IPv6 address succeeds. If the DAD for
IPv6 address fails then no actions are taken for domain name. When
DAD fails for stateless address autoconfiguration, then the domain
configuration starts only when the address has been configured using
Stateful Address Configuration methods and the node is going on DAD
for this address.
This scenario starts when a 6DNAC Client receives RA message with
DNS Zone Suffix and other parameters including address prefix as
specified in NDP [2461] and wants configure its IPv6 address (Global
or Site Local) and domain name.
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+---------+ +---------+ +---------+ +---------+
| 6DNAC-A | | 6DNAC-S | | 6DNAC-B | | DNS-S |
+----+----+ +----+----+ +----+----+ +----+----+
| | | |
| | | |
| RA with | | |
| DNS Suffix Opt | | |
|<---------------| | |
| #1 | | |
|-----+ | | |
Construct | | | |
FQDN& | #2 | | |
IPv6 Addr | | | |
|<----+ | | |
DAD/DFQDND Starts | | |
| | | |
| | | |
| NS with | | |
| FQDN Opt | | |
|--------------->+--------------->| |
| #3 | #3 | |
| No Entry | |
| |------+ | |
| Create FQDN | | |
| <FQDN,A> | #4 | |
| |<-----+ | |
| | | |
| | |------+ |
| | My IPv6 Addr| #5 |
| | |<-----+ |
| | Defend DAD | |
| | with NA | |
|<---------------+<---------------| |
| #6 | #6 | |
| Entry | |
| |------+ | |
| Delete FQDN | #7 | |
| |<-----+ | |
| | | |
|----+ | | |
DAD Failed | #8 | | |
Stop DFQDND | | | |
|<---+ | | |
| | | |
v v v v
<Figure: 12 DAD failure>
#1. 6DNAC Server sends out Router Advertisement to 6DNAC Client-A.
#2. 6DNAC Client-A constructs IPv6 Address based on the prefix and
FQDN as per Host Naming Algorithm.
#3. It then starts Duplicate address & FQDN Detection, for the newly
constructed IPv6 address and FQDN, and sends out DAD/DFQDND NS
with FQDN option.
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#4. 6DNAC Server processes the DAD/DFQDND NS message and finds
that there is no entry for the FQDN in its cache. And,
creates Cache entry as <FQDN, A> and starts a Registration
timer with RegistrationWaitTime seconds.
#5. 6DNAC Client-B finds that the DAD/DFQDND-NS target address is
in its unicast address list.
#6. It then starts defending DAD by sending NA to all-nodes multicast.
#7. 6DNAC Server finds that the DAD has failed for 6DNAC Client-A.
And, deletes its FQDN Cache entry <FQDN,A>.
#8. 6DNAC Client gets defending DAD-NA and desists from DAD.
And also, stops Duplicate FQDN Detection as well.
At this point the address must be configured using stateful
methods and the domain name registration starts with the DAD
for the newly constructed IPv6 address.
7.3. DNS Zone Suffix Discovery and FQDN Construction
7.3.1. Sending Router Advertisement Messages
Routers send out Router Advertisement message periodically,
or in response to a Router Solicitation. Router should include
the DNS Zone Suffix Option in their advertisements. If the DNS
Zone Suffix changes (similar to Site Renumbering), then it should
advertise the Old Zone Suffix with zero Valid Lifetime and New
Zone Suffix with proper non-zero Valid Lifetime. In any other
case, a router should not send this option twice in a single
router advertisement.
7.3.2. Processing Router Advertisement Messages
For each DNS Zone Suffix Option in Router Advertisement,
a. 6DNAC node stores the Zone Suffix information in its local
database. Also, constructs FQDN as per Host Naming Algorithm.
b. If the node has not configured FQDN yet,
1. If the node is going to perform DAD for either Site local or
Global Address, then it should include FQDN option to perform
Duplicate FQDN Detection in parallel with DAD.
2. If the node has already got either Site local or Global
address, then it should send out NS with FQDN option and
unspecified target address to perform Duplicate FQDN
Detection.
c. If the node has already configured FQDN, and if the
advertisement carries two DNS Zone Suffix Options,
First DNS Zone Suffix should match with the configured FQDN
Suffix and its Valid Lifetime must be zero. Second DNS Zone
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Suffix should have non-zero Valid Lifetime. In this case, the
node constructs new FQDN based on the new DNS Zone Suffix (from
second DNS Zone Suffix option), and perform Duplicate FQDN
Detection with unspecified target address. Also, it should
overwrite the old FQDN with the newly constructed FQDN.
7.3.3. FQDN Lifetime expiry
6DNAC Server:
It should delete the FQDN cache entry and should de-register from
the DNS Server.
6DNAC Client:
It should send update to 6DNAC Server by restarting the Duplicate
FQDN Detection.
7.3.4. Host Naming Algorithm
A node constructs FQDN by combining DNS Zone Suffix and the hostname
as depicted in the following diagram.
+------------------+----------------------------------+
| Host Name | Advertised Suffix |
+------------------+----------------------------------+
<Figure 13: Fully Qualified Domain Name format>
A node can choose Host Name using any of the following methods:
a. String form of random number generated from the Interface
Identifier.
b. List of configured Host Names provided by the administrator.
The number of retries must be specified in this algorithm in
case of domain name duplication.
7.4. Duplicate Domain Name Detection
The procedure for detecting duplicated FQDNs uses Neighbor
Solicitation and Advertisement messages as described below.
If a duplicate FQDN is detected during the procedure, the
FQDN cannot be assigned to the node.
An FQDN on which the DFQDND Procedure is applied is said
to be tentative until the procedure has completed successfully.
A tentative FQDN is not considered "assigned to the node" in the
traditional sense. That is, the node must accept Neighbor
Advertisement message containing the tentative FQDN in the FQDN
Option.
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It should also be noted that DFQDN must be performed prior to
registering with DNS Server to prevent multiple nodes from using
the same FQDN simultaneously. All the Duplicate Address Detection
Neighbor Solicitation messages must carry Source Link Layer Address
Option as specified in NDP [2461].
The detection of duplicate FQDN can be achieved through one of the
following three types of procedures.
1. DAD with All Nodes Multicast Address
2. DAD with Router Alert Option for 6DNAC.
3. Explicit Detection of Duplicate Domain Name
Even though three solutions are listed, authors prefer only one
procedure to be followed in future based on further analysis and
comments received from others.
7.4.1. DAD with All Nodes Multicast Address
7.4.1.1. Sending Neighbor Solicitation Messages
6DNAC Client sends Neighbor Solicitation Messages as part
of Duplicate Address Detection SLAAC [2462] with the following
extra information and modifications:
a. Include FQDN Option in the DAD Neighbor Solicitation Message
b. Destination Address is set to All Nodes Multicast Address
There may be a case where DAD has succeeded but DFQDND is in Retry
Mode. In such case, the Neighbor Solicitation must carry unspecified
address in the ICMP target address field and new domain name in FQDN
option to re-try the registration of the domain name.
7.4.1.2. Processing Neighbor Solicitation Messages
6DNAC Clients must ignore the FQDN option found in any of the
neighbor solicitation messages.
6DNAC Server processes FQDN Option found in the Duplicate Address
Detection Neighbor Solicitation Messages as described below:
Lookup FQDN Cache for the domain name in FQDN Option.
If the entry exists and
i. Link Layer Address matches with SLLA option, this is the case,
where node has changed its IPv6 address or updating the valid
life time. 6DNAC Server updates its cache and also updates DNS
Server using DDNS-UPDATE. If there is no change in IPv6 address
or life time then no updates are sent to the DNS server.
ii. Link Layer Address differs with SLLA option, defend the duplicate
FQDN Detection by sending Neighbor Advertisement Message as
described in $7.4.1.3$.
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else,
Lookup FQDN Cache for the Link Layer Address in SLLA Option.
If the entry exists, update the FQDN Cache and update DNS Server
using DDNS-UPDATE. This is the case, where node has changed its
domain name (similar to Site Re-numbering).
If then entry does not exists, then it means that this is the new
registration. It must create a cache entry and start Registration
timer with RegistrationWaitTime. At the expiry of the Registration
timer, it should update DNS Server with DDNS-UPDATE.
7.4.1.3. Sending Neighbor Advertisement Messages
6DNAC Server sends Neighbor Advertisement Messages as part
of Duplicate Address Detection SLAAC [2462] with the FQDN Option
in Neighbor Advertisement message to defend duplicate FQDN
detection.
There may be the case where defending of duplicate address detection
is not required but defending of FQDN is required. In such instance,
the defending Neighbor Advertisement must carry FQDN and unspecified
address in the ICMP target address field.
7.4.1.4. Processing Neighbor Advertisement Messages
6DNAC Server must ignore the any FQDN option found any of
the neighbor advertisement messages. If the Neighbor Advertisement
is a DAD defending, then it must delete its FQDN Cache entry created
on the reception of DAD Neighbor Solicitation message.
When 6DNAC Clients gets the duplicate address detection neighbor
advertisement messages with FQDN option set it means that its
duplicate FQDN detection failed and enters Retry Mode.
7.4.1.5. Pros and Cons
The advantage of this procedure is that it does not need any
extension header options to be included. The disadvantage of this
procedure is that, it needs change in the existing DAD procedure.
The change is only that the DAD neighbor solicitations are to be
addressed to all nodes multicast address instead of solicited
node multicast address. The another disadvantage is that, it needs
the existence of Duplicate Address Detection Procedure to
perform duplicate FQDN detection.
7.4.2. DAD with Router Alert Option for 6DNAC
7.4.2.1. Sending Neighbor Solicitation Messages
6DNAC Client sends Neighbor Solicitation Messages as part
of Duplicate Address Detection SLAAC [2462] with the following
extra information:
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a. Include Hop-by-Hop extension Header with Router Alert Option
for 6DNAC as described in IPv6 Router Alert Option[2711].
b. Include FQDN Option in the DAD Neighbor Solicitation Message
7.4.2.2. Processing Neighbor Solicitation Messages
This is same as described in $7.4.1.2$.
7.4.2.3. Sending Neighbor Advertisement Messages
This is same as described in $7.4.1.3$.
7.4.2.4. Processing Neighbor Advertisement Messages
This is same as described in $7.4.1.4$.
7.4.2.5. Pros and Cons
The advantage of this procedure is that it does not disturb
the existing implementation and their way of processing the
packets. The disadvantage is that, it needs the existence
of Duplicate Address Detection Procedure to perform duplicate
FQDN detection. Another disadvantage is that this procedure
requires 6DNAC Server functionality to be implemented on Router.
However, in this case 6DNAC Server can serve multiple links.
7.4.3. Explicit Detection of Duplicate Domain Name
In this procedure Duplicate FQDN Detection starts after completion
of successful Site local or Global Address configuration.
7.4.3.1. Sending Neighbor Solicitation Messages
6DNAC Client sends Neighbor Solicitation Messages as part
of Duplicate FQDN Detection with the following information:
a. Include FQDN Option in the Neighbor Solicitation Message
b. Destination Address is set to All Nodes Multicast Address
or uses Router Alert Option for 6DNAC, when 6DNAC Server is
implemented on router.
c. Target Address is set to Unspecified Address
d. Other fields are set as per DAD SLAAC [2462].
7.4.3.2. Processing Neighbor Solicitation Messages
This is same as described in $7.4.1.2$.
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7.4.3.3. Sending Neighbor Advertisement Messages
This is same as described in $7.4.1.3$.
7.4.3.4. Processing Neighbor Advertisement Messages
This is same as described in $7.4.1.4$.
7.4.3.5. Pros and Cons
The advantage of this procedure is that it does not need the
existing duplicate address detection procedure. This is introduced
as the DAD procedure is found to be redundant in when IPv6 addresses
are constructed from the interface ID [DIID].
Note that, if 6DNAC Clients know the address of 6DNAC Server then
they can directly send DFQDND-NS to 6DNAC Server.
7.4.4. Retry Mode for Re-registering Domain Name
In retry mode, nodes construct new FQDN as per Host Naming Algorithm.
Then they restart Duplicate FQDN Detection as described in $7.4.3$.
7.5. Domain Name Registration
6DNAC Server must be an authenticated to update the DNS Server.
6DNAC Server must also be configured with the DNS Server
information.
6DNAC Server detects the DNS information (IPv6 Address and
corresponding FQDN) from DAD/DFQDND messages and caches the
information. It also have an associated Registration Timer with
RegistrationWaitTime to wait for the successful completion of
DFQDND and update DNS Server using existing protocol DDNS UPDATE
[2136].
8. Security Consideration
If someone wants to hijack correct Domain Name registration, they
could send a NS message with incorrect or same Domain Name to the
6DNAC server repeatedly and server would start the Domain Name
registration through above mechanism, which is a security hole.
As described in [2461], a host can check validity of NDP messages.
If the NDP message include an IP Authentication Header, the message
authenticates correctly. For DNS UPDATE processing, secure DNS
Dynamic Update is described in [3007].
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9. IANA Consideration
Values in the Router Alert Option are registered and maintained by
IANA. For 6DNAC, the value has to be assigned by IANA. Also IANA is
required to assign the Type values for DNS Zone Suffix Information
option and FADN option.
10. Acknowledgement
Special thanks are due to Badrinarayana N.S. and Christian Huitema for
many helpful suggestions and revisions.
11. Intellectual Property
The following notice is copied from RFC 2026 [Bradner, 1996],
Section 10.4, and describes the position of the IETF concerning
intellectual property claims made against this document.
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use other technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances
of licenses to be made available, or the result of an attempt made
to obtain a general license or permission for the use of such
proprietary rights by implementers or users of this specification
can be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
12. Copyright
The following copyright notice is copied from RFC 2026 [Bradner,
1996], Section 10.4, and describes the applicable copyright for this
document.
Copyright (C) The Internet Society July 12, 2001. All Rights
Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
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and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph
are included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
13. References
[2373] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 2373, July 1998.
[2460] Deering, S. abd R. Hinden, "Internet Protocol,
Version 6 (IPv6) Specification", RFC 2460,
December 1998.
[2461] Narten, T., Nordmark, E. and W. Simpson, "Neighbor
Discovery for IP version 6(IPv6)", RFC 2461, December
1998.
[2462] S. Thomson and Narten T, "IPv6 Stateless Address Auto-
Configuration", RFC 2462, December 1998.
[2711] C. Patridge and A.Jackson, "IPv6 Router Alert Option",
RFC 2711, October 1999.
[1034] P. Mockapetris, "DOMAIN NAMES - CONCEPTS AND
FACILITIES", RFC 1034, November 1987.
[1035] P. Mockapetris, "Domain Names - Implementation and
Specification" RFC 1035, November 1987.
[2136] P. Vixie et al., "Dynamic Updates in the Domain Name
System (DNS UPDATE)", RFC2136, April 1997.
[3007] B. Wellington, "Secure Domain Name System (DNS) Dynamic
Update", RFC 3007, November 2000.
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[DIID] yokohama-dad-vs-diid.pdf
at http://playground.sun.com/ipng/presentations/July2002/
[DNSISSUES] Durand, A., "IPv6 DNS transition issues", draft-ietf-
dnsop-ipv6-dns-issues-00.txt, work in progress.
[PREFIX] S. Miyakawa, R. Droms, "Requirements for IPv6 prefix
delegation", draft-ietf-ipv6-prefix-delegation-
requirement-01.txt, work in progress.
[Autoreg] H. Kitamura, "Domain Name Auto-Registration for
Plugged-in IPv6 Nodes", draft-ietf-dnsext-ipv6-name-
auto-reg-00.txt, work in progress.
[NIQ] Matt Crawford, "IPv6 Node Information Queries", <draft-
ietf-ipngwg-icmp-name-lookups-09.txt>, work in progress.
14. Author's Addresses
Soohong Daniel Park
Mobile Platform Laboratory, SAMSUNG Electronics, KOREA
Phone: +82-31-200-3728
Email:soohong.park@samsung.com
Syam Madanapalli
Network Systems Division, SAMSUNG India Software Operations, INDIA
Phone: +91-80-5550555
Email:syam@samsung.com
Park & Madanapalli Expires October 2003 [Page 30]
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