S.Gopinath Rao
Internet Draft NRG, USM Malaysia
Document : <draft-gopinath-ipv6-hostname-auto-
reg-02.txt> K. Ettikan
Expires in six months Intel ASG, Malaysia
3 December 2002
IPv6 Hostname auto-registration Procedure
<draft-gopinath-ipv6-hostname-auto-reg-02.txt>
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
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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
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Abstract
This document describes a new method, which will automatically
acquire the host name of active IPv6 nodes and register it to the
local Domain Name System (DNS) server. Active IPv6 nodes are nodes
that are connected to a network.
Our proposed new method [6] will automatically learn some useful
information from all the IPv6 nodes, such as the host name and the
IP address. The Agent using a new method will keep all the
information that is send by the nodes. The Resolver will add the
host name together with the IPv6 address to the DNS. This will be
implemented without the need for any changes at the clients' site.
The objective of this document is to specify a new procedure and
also the algorithm used in the procedure.
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Table of Content
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Study on Existing and similar application . . . . . . . . . . . 3
2.1 Domain Name Auto-Registration for plugged in IPv6 . . . . . 4
3. Design of the new auto-registration procedure . . . . . . . . . 4
3.1 Design Issue . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Design Method . . . . . . . . . . . . . . . . . . . . . . . 5
3.2.1 The Agent . . . . . . . . . . . . . . . . . . . . . . . 6
3.2.2 The Resolver . . . . . . . . . . . . . . . . . . . . . 6
3.2.3 Agent-Resolver Communication . . . . . . . . . . . . . 7
3.3 Detection method . . . . . . . . . . . . . . . . . . . . . . 9
3.3.1 Detecting the nodes. . . . . . . . . . . . . . . . 11
3.3.2 Algorithm for using unicast address as destination in
the ICMPv6 packet . . . . . . . . . . . . . . . . . . . 11
3.3.3 Algorithm for using multicast address as destination in
the ICMPv6 packet . . . . . . . . . . . . . . . . . . 12
3.4 Updating the DNS by the Resolver . . . . . . . . . . . . . . 13
3.4.1 Naming . . . . . . . . . . . . . . . . . . . . . . . . 13
3.4.2 Naming Algorithm . . . . . . . . . . . . . . . . . . . 14
3.5 Location of the Agent and the Resolver in a network . . . . 14
4. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5. Security Consideration . . . . . . . . . . . . . . . . . . . . 16
6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
Domain Name System has long been used for resolving host name to IP
address and vice versa. The need of automatically sensing the host
name and IP addresses on a network by DNS does not arise because
IPv4 addresses are easy to remember. The improvement of DNS with the
introduction of DNSv6 should have included this new feature so that
it would be an intelligent application.
The reason for the proposed method and the solutions are as follows.
1. The main factor that drives us to introduce this procedure is
the IPv6 addressing scheme. 128 bits IPv6 address is indeed very
long to remember compared to IPv4. This hexadecimal
representation makes unit of network difficult to be identified
and remembered based on this IP address. Instead of remembering
oneÆs IP address, it will be easier for us to just use the host
name.
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To solve this problem, a new registration procedure that will
automatically sense all the IPv6 nodes on a specific link and
add all the names of the nodes within that domain to its DNS.
This will also give the users the freedom to choose their own
host name for their node/s. An algorithm will be used to make
sure that the host name is unique within the domain.
2. Maintenance of these addresses is another hassle for system
administrator. In current DNS, system administrators manually
enter the host name and the IP address associated with it into
the host name file or the DNS. Whenever there is a change to a
node in the domain, system administrator must manually edit the
host name file to make sure that the new nodeÆs information is
updated to the list.
To solve the above-mentioned problem, the new procedure will
periodically check and update the nodesÆ information into the
host name file, if there are changes to the nodes. Even though
we can use dynamic update [8] to send updated information to the
DNS, this is restricted to certain operating system that
implements the dynamic update.
By using this procedure, cost of handling and maintaining the host
names can be reduced in huge amount. The amounts of time spend by
system administrator on setting up the host names will also be
reduced.
This document proposes a new procedure to dynamically handle the
host names on an IPv6 LAN, which is named IPv6 Hostname DNS auto-
registration procedure. This document also describes the algorithm
used in the new procedure.
The implementation of this procedure involves few existing methods.
For example, to get the nodes information, the use of Neighbor
solicitation (Duplicate Address Detection (DAD) packet) and also the
ICMPv6 packet will be implemented. This new procedure supports all
types of IPv6 addresses available, both the stateless [1] and
statefull IPv6 addresses. This includes link local addresses, site
local addresses and global unicast addresses.
2. Study on existing and similar application [6]
The dynamic naming of host name was not implemented in IPv4 because
IPv4 are easy to remember compared to IPv6 addresses. The only
similar proposed method was discussed in a draft titled Domain Name
Auto-Registration for plugged in IPv6 [3].
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2.1 Domain Name Auto-Registration for plugged in IPv6
<draft-kitamura-ipv6-name-auto-reg-00.txt>
This draft has proposed to use a method for domain name auto-
registration for plugged in IPv6 nodes. The method is divided into 2
functions, which are ôdetectorö function and ôregistrarö function.
The ôdetectorö is used to detect the appearance of new IPv6 nodes
and send it to a ôRegistrarö. The ôRegistrarö is used to prepare
appropriate domain name information for registration and to register
it by sending dynamic update messages to the corresponding request.
Two approaches are used in the draft to detect the nodes. One of the
methods is by detecting the DAD packets. The other approach is by
using the SNMP procedure. The setback of this method is that it
needs to be implemented at both the client and the server site. A
new Internet standard like ICMP needs to be set for this approach to
work.
Our proposed protocol is similar to the above draft except that our
protocol uses the DAD together with the ICMPv6 packet to get the
host name.
Some of the idea discussed in this approach can be shared to produce
a better method and algorithm.
3. Design of the new auto-registration procedure
This section describes the design of the new procedure, IPv6
Hostname auto-registration procedure [9]. The algorithm used in this
procedure to solve the above mentioned problems would also be
discussed in this section.
3.1 Design Issue
The new auto-registration procedure can be incorporated into the
existing DNS. There are few issues involved in designing this
procedure.
1. Assignment of multiple IPv6 addresses to a single interface
makes names assignment a complex problem. Each IPv6 active nodes
is capable of having multiple IP addresses that may have
different reachability scope (link local, site local or global).
It can get the IPv6 address using both stateless and statefull
configuration method. The IPv6 nodes will have a default link
local address, which is configured automatically using the
autoconfiguration method [1]. Each node would also be able to
construct itÆs own global address using the prefix advertised by
a router on the same link. Beside that we can also manually
assign a global IPv6 address to that same interface. So, we
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must make sure that all the addresses point to the same host
name, unless the system administrator wants to configure each IP
addresses with different host names. To select an address that
will bind to the host name, default address selection can be
used [10]. The default address selection is a method to select a
source address or a destination address from multiple addresses
that is assigned to a single interface.
2. The implementation of a new method usually requires a lot of
changes at both the server and the client. To minimize the
changes on nodes, the new proposed procedureÆs implementation
required the development at only one site. This is implemented
using the existing methods available, which supports all
operating systems. Some of the methods developed uses the ICMPv6
and the neighbor discovery in IPv6. This will not only reduce
the impact of introducing new protocol in the Internet but also
make the implementation of new system much easier.
3. The locations of the entities on the network need to be decided.
This is to make sure that optimum results can be achieved. If a
DNS is shared between 2 LANs, the entities must be implemented
so that it can detect all the nodes in both the LANs. This is
because the DAD and the ICMPv6 packets used for detection of the
nodes wonÆt be able to pass through the router that separates
the LANs.
3.2 Design Method
Hostname auto-registration procedure is composed of 2 entities, the
Agent, which detects all the IPv6 nodes on a link and the Resolver,
which updates the DNS with the latest host name information received
from the Agent/s.
+-+-+-+-+-+-+-+
| +=========+ |
| | R | |
| +=========+ |
| |
| +=========+ |
| | Agent | |
| +====+====+ |
+-+-+-+||-+-+-+
||
||
+-+-+-+||-+-+-+
| +=========+ |
| | Resolver| |
| +====+====+ |
| | |
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Internet Draft IPv6 auto-registration procedure 3 December, 2002
| +====+====+ |
| | DNS | |
| +=========+ |
+-+-+-+-+-+-+-+
Fig. 1 The Overall architecture of the new procedure
Figure 1 shows the overall architecture of the new procedure and the
communication between the two entities. The Agent resides on a
router while the Resolver is placed together with the DNS. The Agent
sends the information it captures to the Resolver using the
communication pipe between the two entities.
3.2.1 The Agent
The AgentÆs function is to detect all the nodes on a link and keep
the information in a specific file. It uses two detection methods
for getting the information from a node. The methods are using the
DAD packet and the ICMPv6 packet. The detection of DAD packets is
restricted on a single LAN because the router wonÆt allow the DAD
packets to pass through. So, the Agent must be placed on all the
LANs in order to detect the DAD packets issued by the nodes. The
best location for the Agent to be placed is with the router.
The Agent need to be manually configured first so that the
information that it detects from the IPv6 nodes can be send to the
Resolver to be updated into the DNS. It will also do periodic
checking on the LAN to make sure that new changes to the nodes are
updated to the DNS.
3.2.2 The Resolver
This entity sets an appropriate host name for registration into the
corresponding DNS server. The host name is created from the
information that is sent by the Agent. It later updates the host
name into the DNS.
The Resolver must have a method to verify the uniqueness of the host
name in the network. This is achieved by using the naming algorithm
to name the nodes. This algorithm is also used to minimize the
effects of misconfigured registration request by the nodes. All the
names given by the Agent is kept in a specific file. This is to make
sure that the information can be retrieved easily whenever
necessary.
The Resolver must be configured so that it directly updates the
nodesÆ information to the DNS.
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The main file in the Resolver consists of all the information send
by the Agents. After updating the file, it will be copied by the
Agent for their reference. This is important because a same node
will move from one subnet to another subnet with same information.
This scenario is further described in the next section.
In order to make the Resolver to work effectively, it must be placed
together with the DNS. This will make sure that the information is
updated as soon as the Resolver received it from the Agent.
3.2.3 Agent-Resolver Communication
All the Agents, which communicate to the same Resolver, will have a
copy of the updated database from the Resolver. This database will
be used to check if changes occur to a node as described below.
The link local address of each machine will be added in a new file.
This address will be bind together with the global address and the
host name of the machine in the file. The link local address can be
used to check the uniqueness of the machine because the link local
address is unique as it is generated using the Ethernet address and
it never changes wherever the node moves. This information will be
compared every time the Agent receives the updated information from
a node before the host name is updated to the DNS via the Resolver.
In the development of the Agent and the Resolver, multi-link
scenario needs to be taken into consideration. It is a situation
where a node moves from one subnet to another subnet and uses a same
DNS. It is possible for few scenarios to happen when a node moves
from one subnet to another and when some changes happened to a node.
1. A node uses new IP address but same host name and NIC card.
This is a complicated scenario. In this case, the link local
address together with the new global address will be compared
with the information in the AgentÆs database. Since the link
local address is still in the database, the old global address
associated with the link local address will be deleted from the
Resolver. The new global address will be updated to the
database. With this algorithm we can maintain the host name and
at the same time change the global address.
2. A node uses new IP address using new NIC card but same host
name
This is same as two nodes asking the same host name. In this
situation, the naming algorithm will give a new name for the
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node. The old data will be overwritten after some time depends
on system administrator (see section (g)). Until then the node
has to use a new name generated using the naming algorithm or
change the host name. This can be overcome if system
administrator manually deletes the old information. The same
host name cannot be used to avoid multiple updates by a node
that uses the same name. This will be a hassle because every
time a new node with same name activated, it will overwrite the
old IP address. With this, some of the host name will be
missing from the list.
3. A node changes both host name and IP address replacing old
information
The new information will be compared with the information in
the file. First the algorithm will check the link local
address in the file. Since the link local address is already in
the file, the global and the host name will be compared. If
both the information is new, then the old will data be over
written with the new information. The Agent will send this
updated information to the Resolver. The Resolver will then
update the new information of the node to the DNS.
4. A node uses a new NIC card with old IP address and Host Name
First the link local address will be compared with link local
address in the file. If there is no entry, then the link local
address will be entered and the host name will be compared with
the list. If the host name is already exist, then a new name
will be generated. If not, the host name will be entered
together with the link local address and global IP address.
5. A node uses new NIC and Host Name but old IP address
This is similar to scenario (4) above.
6. A node changes the host name but uses the same IP address
The link local address of the specific node will be compared
with the link local addresses in the file. If the IP address is
already in the file, then the global IP address will be
compared. If there is no change, then the host name will be
compared. The new host name will overwrite the existing host
name in the file before updating it in the DNS.
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7. A node is inactive for certain duration
This is a case when a node doesnÆt response to AgentÆs query.
This scenario is possible when a node is crashed or not booted
by the owner for some time. The Agent will check the node for 3
or 4 months (depends on the setting. If the node is still
inactive after the duration, the information will be
overwritten by new a node requesting for the same name. If the
owner wants to keep the information after that time period,
system administrator need to set a flag in the DNS indicating
not to delete the nodeÆs information. This flag can be set as
an additional field in the DNS or in the Resolver.
8. Two or more nodes request for the same host name
Using the naming algorithm (section 3.4.1 & 3.4.2), the nodes
will be given the name requested using first come first serve
basis. When the nodes rebooted, the names will be maintained as
given earlier.
3.3 Detection Method
This is the main method in the new procedure. In this method, the
Agent will detect any new IPv6 nodes on a link, check the uniqueness
of that node on that link and then update the information in the
DNS.
There are 2 kinds of detection method used in the procedure. Both
the detection methods enable a mechanism to work without the
introduction of a new protocol and without any functions installed
into the IPv6 nodes. This two methods need to be combined to make
sure that the nodes are configured correctly with the host name in
the DNS.
1. Duplicate Address Detection (DAD)
The nodes can be detected by monitoring the duplicate address
detection (DAD) packet issued by nodes that has been activated.
The DAD packet is issued as part of neighbor solicitation in
neighbor discovery [2]. The implementation of duplicate address
detection is compulsory on all IPv6 nodes, regardless of whether
they are obtained through stateful, stateless or manual
configuration. DAD has the same functions as the ARP packet in
IPv4 but DAD provides more information. It is issued to ensure
that all configured addresses are likely to be unique on a given
link [1].
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By monitoring the DAD packets on a link, the Agent will capture
it and the packets will be analyzed. Then using ICMPv6 packet,
the Agent will issue a query to that node for more information
(see section 2 of 3.3). All the information that has been
captured will be kept in a specific file for reference and send
to the Resolver. It should be noted that the DAD packets could
only be detected on a link-local, thus the Agent must be
positioned on a specific location to detect the packets (see
section 3.4).
2. ICMPv6 û node information query and node information reply
This is the most important part in the Agent. ICMPv6 type that
will be in the Agent are node information (NI) query and node
information reply. The use of ICMPv6 NI query as type 139 and
ICMPv6 NI reply type 140 is already defined in [4]. Currently
the ICMPv6 packet type for querying nodes information is still
in the process of upgrading. Node information query and node
information reply are information-based messages. NI query
packet is sent by the ôQuerierö node to ask some information
from the ôResponderö node. The ôResponderö node, upon receiving
the ICMPv6 NI query packet, replies to the querier with the
information requested by the ôQuerierö node.
This will be an exact method that will be used by the Agent to
query IPv6 nodes on a link. The ICMPv6 packet can be addressed
to a unicast address, a link local multicast address or an
anycast address depending on the scope of the information
required. In this implementation we will skip the use of anycast
and only use the unicast and the multicast address for querying
information.
The ICMP source address should be that of the address where the
Agent reside. This is to make sure that the reply is send back
to the Agent. The destination address can be chosen from the 2
types of addresses according to the algorithm. There will be 2
scenarios for choosing the destination address:
i) If a node has been detected by capturing the DAD packet,
then the destination address will be the unicast address of
the detected node. After getting the IPv6 address from the
DAD packet, the Agent will use it as a destination address
in the ICMPv6 NI query requesting for host name (type 2 for
qtype field in the ICMPv6 NI query).
ii) The Agent uses the predefined link local multicast address,
which is FF02::1 as the destination address to do periodic
checking on a link to detect any changes or updates to a
node. This query need to be sent from time to time so that
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Internet Draft IPv6 auto-registration procedure 3 December, 2002
the changes can be detected earlier to make the new
procedure efficient. The frequency of sending this type of
packets will also need to be considered. Even though the
ICMPv6 packets send are small, if it is send too frequent,
it might flood the network. For it to work efficiently the
internal time taken for sending the ICMPv6 packet need to be
acceptable.
The content of qtype in the ICMPv6 packet that will be used by
the Agent is either type 2 (DNS names) or 3 (Node Addresses) and
the implementation of the Agent is done with an assumption that
all the nodes are configured with the latest ICMPv6, which
implements the ICMPv6 node information query. Upon receiving an
ICMPv6 NI query, the nodes must check the queryÆs IPv6
destination address and discard it if it is not intended for the
node. The destination address of the query should be either the
IP address of the receiving node or the multicast address that
the receiving node joined earlier. The use of these ICMPv6 type
is described is detail in the IPv6 Node Information Queries
draft [4].
3.3.1 Detecting the nodes
The Agents continuously monitor for DAD packets in the network. The
DAD packets that it captures will be analyzed. It will compare IP
address with the information in the database the Agent copied from
the Resolver. If the IP address is already exists in the database,
the Agent will further query the host name of the node. If there is
no information in the database, the Agent will further query the
node using the ICMPv6 packet. After getting the necessary
information, the Agent will pass the information to the Resolver.
BEGIN
1. AGENT MONITORS FOR DAD PACKETS AND CAPTURES IT
CHECK IF IP ADDRESS EXISTS IN AGENTÆS FILE
IF EXIST
THEN IGNORE THE DAD PACKET
ELSE GOTO STEP 2
2. USE ICMPV6 PACKET TO REQUEST THE INFORMATION FROM THE NODE
END
3.3.2 Algorithm using unicast address as destination in the ICMPv6
packet
The Agent sends unicast ICMPv6 query to a specific node requesting
more information about the node. If there is no reply from the node,
the Agent will request again. The Agent will kept requesting for few
times if there is no reply from the node. Once the node replied, the
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Internet Draft IPv6 auto-registration procedure 3 December, 2002
Agent will extract the information and send it to the Resolver if
the information is new or some changes occurred the node.
BEGIN
1. AGENT SENDS ICMPV6 UNICAST QUERY
2. AGENT CAPTURES THE REPLY
IF NO REPLY FROM THE NODE
GOTO STEP 1
ELSE
EXTRACT INFORMATION AND UPDATE THE FILE
END
3.3.3 Algorithm using multicast address as destination in the ICMPv6
packet
This algorithm is similar to unicast query. The different is the
target node/s is a multicast group. Once the Agent received the
reply from the node, it will queue the information and check in the
database copied from the Resolver. If there are changes, then the
Agent will send the updated data to the Resolver.
BEGIN
1. AGENT SEND MULTICAST QUERY REQUESTING INFORMATION
2. AGENT READS THE QUEUE (REPLY FROM NODES)
IF IT IS NOT EMPTY
GOTO STEP 3
ELSE GOTO END
3. CHECK THE INFORMATION CAPTURED
IF INFORMATION IS NEW
GOTO STEP 4
ELSE IF INFORMATION EXISTS BUT PART OF IT IS DIFFERENT
GOTO STEP 5
ELSE IF INFORMATION IS SAME
GOTO STEP 2
4. UPDATE THE FILE
GOTO STEP 2
5. CHANGE INFORMATION IN THE FILE WITH THE NEW INFORMATION
GOTO STEP 2
END
3.4 Updating the DNS by the Resolver
The ResolverÆs function is to update the DNS with the information
received from the Agent/s. It will receive the information from the
Agent/s and will activate the naming algorithm before updating it to
the DNS. The Resolver must be configured to communicate with the DNS
server so that the information received will be automatically
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updated. The naming algorithm is used to make sure that the names
are unique in link.
3.4.1 Naming
The unique feature of the auto-registration procedure is the naming
of the IPv6 nodes. The procedure allows the users to set their
preferable name for their IPv6 node/s. Even though we donÆt have the
control over the naming, the procedure still decides whether to use
the specific name given by each user to their nodes. System
administrator also has a choice to use this algorithm or manually
configure the names. He also can use both manual and the approach
described in this document.
The Resolver uses first come first serve basis in the naming
algorithm. If there is a conflict of names between 2 IPv6 nodes, the
node that registered first will be given the name. For the second
node, a new name will be generated using the name given by the node.
For example if the conflict name is ôipv6-dnsö, then the algorithm
will assign a new name for the second node based on that conflict
name such as ôipv6-dns-2ö. In this way the each node will still have
a unique name.
The technique used in this draft is different from the approach
documented in ôDomain Name Auto-Registration for Plugged-in IPv6
Nodesö [3]. In that approach, the naming is still handled by system
administrator and no freedom given to each user. The second
approach, in that draft, uses predefined name, which the registrar
randomly generates. He also uses a method to detect the names
automatically but in the method described, all the nodes must define
a special MIB. This is difficult because it involve both the server
and the client (nodes).
To make the process simpler, we only use 2 ways for naming a node,
which is either configured by system administrator for fix host name
for an IPv6 node or use the name given by the node.
Another important issue is the format of the naming. Before passing
the information captured to the Resolver, the Agent should check if
host name is in a valid format. If it is not, then the information
given by a node will be dropped. This is to ensure that weird names
are not registered into DNS.
3.4.2 Naming algorithm
The Resolver first checks the IP address given by the Agent with the
IP address in its database. If the IP address is new, the Resolver
checks if the name given by the node exists in the database. If not,
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the IP address together with the host name will be registered into
DNS. If the name is already exists, the Resolver will generate a
similar name for the node as mentioned in the previous section.
BEGIN
1. RESOLVER COMPARES THE HOST NAME FILE GIVEN BY THE AGENT WITH
THE ITÆS FILE
IF IP ADDRESS IS NEW
GOTO STEP 2
ELSE GOTO STEP 3
2. CHECK IF NAME IS NEW
IF NAME IS NEW
GOTO STEP 4
ELSE GOTO 5
3. COMPARE THE NAME IN THE FILE THAT IS ATTACHED TO THE IP ADDRESS
IF IT IS NOT SAME
GOTO STEP 5
ELSE END
4. UPDATE IP AND NAME TO THE DNS
END
5. GENERATE A NEW SIMILAR NAME
GOTO STEP 4
END
3.5 Location of the Agent and the Resolver in a network
Since the Agent must be placed to detect the appearance of IPv6
nodes, the location of the Agent is very much restricted.
The best location for the Agent is to be placed together with the
router while the Resolver need to be placed with the DNS. Using this
method, each link will have an Agent, which is manually configured
to directly communicate with the Resolver. This kind of
configuration is needed for the Agent to capture the DAD packets
issued by the nodes. If the Agent is not installed in every link,
the DAD packets cannot be detected because the router will drop all
the DAD packets from going out of it.
+==========+ +#########+
|+--------+| |+-------+|
|| DNS || || Router||
|+---+----|| |+-------+|
| | | |+-------+|
|+--------+| || Agent ||
||Resolver|| |+-------+|
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Internet Draft IPv6 auto-registration procedure 3 December, 2002
|+--------+| +####+####+
+====+=====| |
| |
+----+------+---------+----------+-------+--------+
| |
+====+====+ +====+====+
|IPv6 node| |IPv6 node|
+=========+ +=========+
Fig. 2 The configuration on a single LAN with DNS located in the
same LAN
Figure 2 shows an example configuration of the entities on a single
LAN, with the DNS in the same subnet. In this case, the Agent will
directly communicate with the Resolver to update the host name file.
The Agent will dynamically get all the names and update the Resolver
from time to time. The Resolver will then update the DNS with this
latest information.
+==========+
|+--------+|
|| DNS ||
|+---+----||
| | |
|+--------+|
||Resolver||
|+--------+|
+====+=====|
|
+----------+--------------+---------+-----------+
| |
| |
+####+####+ +####+####+
|+-------+| |+-------+|
|| Router|| || Router||
|+-------+| |+-------+|
|+-------+| |+-------+|
|| Agent || || Agent ||
|+-------+| |+-------+|
+####+####+ +####+####+
| |
-----+-----+--- --------+----+--
| |
+====+====+ +====+====+
|IPv6 node| |IPv6 node|
+=========+ +=========+
Gopinath, Ettikan 3 June 2003 [Page 15]
Internet Draft IPv6 auto-registration procedure 3 December, 2002
Fig.3 Configuration on 2 different LANs sharing one DNS
Figure 3 shows the implementation where one DNS is shared among
nodes from different LANs. In this scenario, each LAN will have an
Agent that will communicate directly with the Resolver that resides
on a DNS. To avoid the conflict of names from different LAN, each
Agent will make a copy of host name files from the Resolver. In the
case of multiple Agents accessing the Resolver at the same time, the
procedure will allow the first Agent to update the changes to the
Resolver. It will be first come first server basis. In this case the
naming of nodes will be organized without the names conflicting with
other nodes from different LAN/s.
4. Conclusion
The implementation of the auto-registration procedure is aimed to
solve two major problems discussed above. In the future the
capability of this new procedure can be extended by adding more
functions and make it more secure in transmitting the data.
5. Security Consideration
Security is one of the main issues in developing this new procedure.
Since the Agent directly sends the information to the Resolver, the
information must be send securely. The other transmission that needs
to be handled securely is between the Resolver and the DNS.
It also must make sure that the message send by the Agent are from
the Agent that is registered with the Resolver. If not the data
should be ignored. This is to make sure that no malicious data being
send to the Resolver.
The security issue for this new technique needs to be discussed
further.
Gopinath, Ettikan 3 June 2003 [Page 16]
Internet Draft IPv6 auto-registration procedure 3 December, 2002
6. References
[1] S. Thompson, T. Narten, ôIPv6 Stateless Address
Autoconfigurationö, RFC 2462, December 1998.
[2] T. Narten, E. Nordmark, ôNeighbor Discovery for IP Version 6
(IPv6)ö, RFC 2462, December 1998.
[3] H. Kitamura, ôDomain Name Auto-Registration for Plugged-in IPv6
Nodesö, <draft-kitamura-ipv6-name-auto-reg-00.txt>, 13 July 2001.
[4] M. Crawford, ôIPv6 Node Information Queriesö, <draft-ietf-
ipngwg-icmp-name-lookups-07.txt>, 28 August 2000.
[5] IEEE, ôGuidelines for 64-bit Global Identifier (EUI-64)
Registration Authorityö,
http://standards.ieee.org/regauth/oui/tutorials/EUI64.html, March
1997
[6] Gopinath Rao Sinniah, Ettikan Kandasamy Karuppiah and R.
Sureswaran, ôHost Name Resolution Protocol (HNRP) û The existing
implementation and the need for a new protocolö, Proceedings IEEE
MICC2001, Kuala Lumpur, October 21-24.
[7] R. Hinden, S. Deering, ôIP Version 6 Addressing Architectureö,
RFC 2373, July 1998.
[8] P. Vixie, S. Thompson, Y. Rekhter and J. Bound, ôDynamic Updates
in the Domain Name Systemö, RFC 2136, April 1997.
[9] Gopinath Rao Sinniah, Ettikan Kandasamy Karuppiah and R.
Sureswaran, ôHost Name Resolution Protocol (HNRP) û The
implementation methodö, Proceedings APAN Conference 2001, Penang,
Aug. 20-22.
[10] R. Draves, "Default Address Selection for IPv6", <draft-ietf-
ipng-default-addr-select-05.txt>, 4 June 2001.
Gopinath, Ettikan 3 June 2003 [Page 17]
Internet Draft IPv6 auto-registration procedure 3 December, 2002
7. Authors' Addresses
Gopinath Rao Sinniah
Faculty of Engineering and Computer Technology,
Asian Institute of Medicine, Science and Technology (AIMST),
2, Persiaran Cempaka, Sungai Petani,
Kedah, Malaysia.
Tel: +604-4422884
Fax: +604-4422881
Email: gopi@nrg.cs.usm.my
Ettikan Kandasamy Karupiah
ASG Penang & Shannon Operations,
Intel Microelectronis (M) Sdn. Bhd.,
Bayan Lepas Free Trade Zone III,
Penang, Malaysia.
Tel: +60-4-859-2591
Fax: +60-4-859-7899
Email: ettikan.kandasamy.karuppiah@intel.com
Gopinath, Ettikan 3 June 2003 [Page 18]