Network Working Group S. Krishnan
Internet-Draft Ericsson
Updates: 4861 (if approved) G. Daley
Intended status: Standards Track NetStar Networks
Expires: March 20, 2010 September 16, 2009
Simple procedures for Detecting Network Attachment in IPv6
draft-ietf-dna-simple-09
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Abstract
Detecting Network Attachment allows hosts to assess if its existing
addressing or routing configuration is valid for a newly connected
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network.
This document provides simple procedures for detecting network
attachment in IPv6 hosts, and procedures for routers to support such
services.
Table of Contents
1. Requirements notation . . . . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Goals . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Applicability . . . . . . . . . . . . . . . . . . . . . . 4
2.3. Link Identification model . . . . . . . . . . . . . . . . 4
2.4. DNA Roles . . . . . . . . . . . . . . . . . . . . . . . . 4
2.5. Working Assumptions . . . . . . . . . . . . . . . . . . . 5
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Host Operations . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. Host data structures . . . . . . . . . . . . . . . . . . . 6
4.2. Steps involved in detecting link change . . . . . . . . . 6
4.3. Link-Layer Indication . . . . . . . . . . . . . . . . . . 7
4.4. Sending Neighbor Discovery probes . . . . . . . . . . . . 7
4.5. Contents of the Neighbor Discovery messages . . . . . . . 8
4.5.1. Neighbor Solicitation messages . . . . . . . . . . . . 8
4.5.2. Router Solicitation messages . . . . . . . . . . . . . 8
4.6. Sending DHCPv6 probes . . . . . . . . . . . . . . . . . . 9
4.7. Response Gathering . . . . . . . . . . . . . . . . . . . . 9
4.7.1. Conflicting results . . . . . . . . . . . . . . . . . 10
4.8. Further Host Operations . . . . . . . . . . . . . . . . . 10
4.9. Recommended retransmission behavior . . . . . . . . . . . 11
5. Pseudocode for Simple DNA . . . . . . . . . . . . . . . . . . 12
6. Constants . . . . . . . . . . . . . . . . . . . . . . . . . . 14
7. Relationship to DNAv4 . . . . . . . . . . . . . . . . . . . . 14
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 14
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
11.1. Normative References . . . . . . . . . . . . . . . . . . . 15
11.2. Informative References . . . . . . . . . . . . . . . . . . 15
Appendix A. Issues with confirming manually assigned addresses . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Requirements notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Introduction
Hosts require procedures to simply and reliably identify if they have
moved to a different IP network to the one which they have been
recently connected. In order to detect change, router and neighbor
discovery messages are used to collect reachability and configuration
information. This information is used to detect whether the existing
router and address prefixes are likely to be present.
This document incorporates feedback from host and router operating
systems implementors, which seeks to make implementation and adoption
of IPv6 change detection procedures simple for general use.
2.1. Goals
The goal of this document is to specify a simple procedure for
detecting network attachment (Simple DNA) that has the following
characteristics.
o Routers do not have to be modified to support this scheme.
o Handle only the simplest and most likely use cases.
o Work at least as quickly as standard neighbor discovery.
o False positives are not acceptable. A host should not conclude
that there is no link change when there is one.
o False negatives are acceptable. A host can conclude that there is
a link change when there is none.
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2.2. Applicability
The Simple DNA protocol provides substantial benefits in some
scenarios and does not provide any benefit at all in certain other
scenarios. This is intentional as Simple DNA was designed for
simplicity rather than completeness. In particular, the Simple DNA
protocol provides maximum benefits when a host moves between a small
set of known links. When a host moves to a completely new link that
is previously unknown, the performance of the Simple DNA protocol
will be identical to that using standard neighbor discovery
procedures [RFC4861]. The Simple DNA procedure provides support for
addresses configured using either IPv6 Stateless Address
Autoconfiguration [RFC4862] or DHCPv6 [RFC3315]. It does not support
manually configured addresses since they are not widely used and can
cause unpredictable results and/or aggressive probing behavior
[Appendix A].
2.3. Link Identification model
Earlier methods of detecting network attachment, e.g. the procedure
defined in [I-D.ietf-dna-protocol], relied on detecting whether the
host was still connected to the same link. If the host was attached
to the same link, all information related to the link such as the
routers, prefixes and configuration parameters was considered to be
valid. The Simple DNA protocol follows an alternate approach where
it relies on probing each previously known router to determine
whether to use information learnt from THAT router. This allows
simple DNA to probe routers learnt from multiple earlier attachments
to optimize movement between a known set of links.
2.4. DNA Roles
Detecting Network Attachment is performed by hosts by sending IPv6
neighbor discovery and router discovery messages to routers after
connecting to a network.
It is desirable that routers adopt procedures which allow for fast
unicast Router Advertisement (RA) messages. Routers that follow the
standard neighbor discovery procedure described in [RFC4861] will
delay the router advertisement by a random period between 0 and
MAX_RA_DELAY_TIME (defined to be 500ms) as described in Section 6.2.6
of [RFC4861]. This delay can be significant and may result in
service disruption. Please note that support for fast unicast RAs is
not necessary since the simple dna procedure can continue to work
using the NS/NA exchange, which will complete earlier than the RA
arrives.
The host detects that the link-layer may have changed, and then
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simultaneously probes the network with Router Solicitations (RSs) and
Neighbor Solicitations (NSs). The host uses advertisements to
determine if the routers it currently has configured are still
available.
Additionally, on links with no statelessly configured addresses, the
host may make use of DHCPv6 procedures to identify an operable
address.
2.5. Working Assumptions
There are a series of assumptions about the network environment which
underpin these procedures.
o The combination of the link layer address and the link local IPv6
address of a router is unique across links.
o Hosts receive indications when a link-layer comes up. Without
this, they would not know when to commence the DNA procedure.
If these assumptions do not hold, host change detection systems will
not function optimally. In that case, they may occasionally detect
change spuriously, or experience some delay in detecting network
attachment. The delays so experienced will be no longer than those
caused by following the standard neighbor discovery procedure
described in [RFC4861].
3. Terminology
+---------------------+---------------------------------------------+
| Term | Definition |
+---------------------+---------------------------------------------+
| Valid IPv6 address | An IPv6 address configured on the node that |
| | has a valid lifetime greater than zero. |
| | |
| Operable IPv6 | An IPv6 address configured on the node that |
| address | can be used safely on the current link. |
+---------------------+---------------------------------------------+
Table 1: Simple DNA Terminology
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4. Host Operations
When a host has an existing configuration for IP address prefixes and
next hop routing, it may be disconnected from its link-layer, and
then subsequently reconnect the link-layer on the same interface.
When the link-layer becomes available again, it is important to
determine whether the existing addressing and routing configuration
are still valid.
In order to determine this, the host performs the detecting network
attachment procedure.
4.1. Host data structures
In order to correctly perform the procedure described in this
document the host needs to maintain a data structure called the
Simple DNA address table (SDAT). This data structure is maintained
by the host on a per interface basis. Each entry in the SDAT table
consists of at least the following parameters.
o IPv6 address and its related parameters like valid lifetime.
o Prefix from which the address was formed.
o Link-local IPv6 address of the router that advertised the prefix.
o Link-layer (MAC) address of the router that advertised the prefix.
o DHCP Unique IDentifier (DUID) in case DHCPv6 was used to acquire
the address [RFC3315].
4.2. Steps involved in detecting link change
The steps involved in basic detection of network attachment are:
o Link-Layer Indication
o Sending of neighbor discovery or DHCPv6 probes
o Response gathering and assessment
These steps are described below.
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4.3. Link-Layer Indication
In order to start Detection of network attachment procedures, a host
typically requires a link-layer indication that the medium has become
available [RFC4957].
After the indication is received, the host considers all currently
configured (non-tentative) IP addresses to be deprecated until the
change detection process completes. It SHOULD also set all Neighbor
Cache entries for the routers on its Default Router List to STALE.
This is done to speed up the acquisition of a new default router when
link change has occurred.
4.4. Sending Neighbor Discovery probes
When a host receives a link-layer "up" indication, it SHOULD
immediately send both a Router Solicitation and if it retains at
least one valid IPv6 address, one or more unicast Neighbor
Solicitations. The Router Solicitation is sent to the All-routers
multicast address using a link-local address as the source address
[RFC4861]. Even if the host is in possession of more than one valid
IPv6 address, it MUST send only one router solicitation using a valid
link-local address as the source address.
For the purpose of sending neighbor solicitations to previous
routers, the host first identifies the set of operable IPv6 addresses
(candidate set) that it wishes to use. If the addresses obtained
from a previous router are no longer valid, the host does not include
these addresses in the candidate set for NS based probing.
For each of the addresses in the candidate set, the host looks up the
SDAT to find out the link-local and MAC addresses of the router that
advertised the prefix used to form the address. It then sends an
unicast Neighbor Solicitations to each router's link-local address it
obtained from the lookup on the SDAT. The host SHOULD NOT send
unicast Neighbor Solicitations to a test node corresponding to an
IPv6 address that is no longer valid.
Please note that the Neighbor Solicitations SHOULD be sent in
parallel with the Router Solicitations. Since sending NSs is just an
optimization, doing the NSs and RSs in parallel ensures that the
procedure does not run slower than it would if it only used an RS.
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4.5. Contents of the Neighbor Discovery messages
4.5.1. Neighbor Solicitation messages
This section describes the contents of the neighbor solicitation
probe messages sent during the probing procedure.
Source Address: A link-local address assigned to the
probing host.
Destination Address: The link-local address of the router being
probed as learnt from the SDAT.
Hop Limit: 255
ND Options:
Target Address: The link-local address of the router being
probed as learnt from the SDAT.
Link Layer Header:
Destination Address: The link-layer (MAC) address of the router
being probed as learnt from the SDAT.
The probing node SHOULD NOT include the Source link-layer address
option in the probe messages.
4.5.2. Router Solicitation messages
This section describes the contents of the router solicitation probe
message sent during the probing procedure.
Source Address: A link-local address assigned to the
probing host.
Destination Address: The all-routers multicast address.
Hop Limit: 255
The probing node SHOULD include a Source link-layer address option in
the probe messages if the address was obtained using DHCPv6 and the
lease has not expired. Otherwise the probing node SHOULD NOT include
the Source link-layer address option in the probe messages.
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4.6. Sending DHCPv6 probes
Where the host has acquired addresses from DHCPv6 or the host does
not have a global prefix, it MAY prefer to use DHCPv6 probe messages
in parallel with the Neighbor Discovery probing. The DHCPv6 probing
procedures described in this document do not imply any changes to the
DHCPv6 protocol or state machine.
In that case, when the host receives a link-layer indication, it
sends a DHCPv6 SOLICIT to All_DHCP_Relay_Agents_and_Servers. This
message contains an Identity Association for either a Temporary
Address (IA_TA) or Non-Temporary Address (IA_NA) [RFC3315]. Where an
existing valid address is being tested for operability, this address
should be placed in the Identity Association's IAADDR element, and
the DUID associated with that address should be copied to the DHCP
SOLICIT from the SDAT.
In order to quickly acquire a new address in the case that link
change has occurred, this SOLICIT message MAY contain the Rapid-
Commit option.
Where the Rapid-Commit option has not been used, a present DHCP
server will respond with an ADVERTISE message. The IP address
contained in the Identity Association (IA_TA or IA_NA) will contain
an IP Address which is operable for the link.
Where Rapid-Commit option has been sent, a DHCPv6 server will respond
with REPLY. In addition to being operable, this address is allocated
to the host for the lease duration indicated in the Identity
Association.
4.7. Response Gathering
When a responding Neighbor Advertisement is received from a test
node, the host MUST verify that both the IPv6 and link layer (MAC)
addresses of the test node match the expected values before utilizing
the configuration associated with the detected network (prefixes, MTU
etc.).
On reception of a Router Advertisement or advertising DHCPv6 message
(a REPLY or ADVERTISE) which contains prefixes that intersect with
those previously advertised by a known router, the host utilizes the
configuration associated with the detected network.
When the host receives an advertisement containing only prefixes
which are disjoint from known advertised prefixes, the host MUST
determine whether the solicited advertisement corresponds to any of
the routers probed via NS. If it does, then the host SHOULD conclude
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that the IPv6 addresses corresponding to that router are no longer
valid. Since any NS probes to that router will no longer provide
useful information, further probing of that router SHOULD be aborted.
Where the conclusions obtained from the Neighbor Solicitation/
Advertisement from a given router and the RS/RA exchange with the
same router differ, the results obtained from the RS/RA will be
considered definitive.
When the host receives a Router Advertisement in reply to the Router
Solicitation it sent, the host SHOULD look for a Neighbor Cache entry
for the sending router and SHOULD mark that router's Neighbor Cache
Entry as REACHABLE if one was found. The host SHOULD add a new
Neighbor Cache Entry in the REACHABLE state for the sending router if
one does not currently exist.
4.7.1. Conflicting results
It is possible that the DHCPv6 based probes and the neighbor
discovery based probes complete with conflicting results. In this
case, the host SHOULD use the following rules to determine the final
result.
o If the DHCPv6 exchange was authenticated, use the result from the
DHCPv6 probe.
o If the DHCPv6 exchange was not authenticated and the neighbor
discovery exchange was protected by SEND [RFC3971], use the result
from the neighbor discovery probe.
o If both the DHCPv6 and neighbor discovery exchanges were not
authenticated, use the result from the DHCPv6 probe
4.8. Further Host Operations
Operations subsequent to detecting network attachment depend upon
whether change was detected.
After confirming the reachability of the associated router using an
NS/NA pair, the host performs the following steps.
o The host SHOULD rejoin any solicited nodes' multicast groups for
addresses it continues to use.
o The host SHOULD select a default router as described in [RFC4861].
If the host has determined that there has been no link change, it
SHOULD NOT perform duplicate address detection on the addresses that
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have been confirmed to be operable.
If the NS based probe with a router did not complete or if the RS
based probe on the same router completed with different prefixes than
the ones in the SDAT the host MUST unconfigure all the existing
addresses received from the given router, and MUST begin address
configuration techniques, as indicated in the received Router
Advertisement [RFC4861][RFC4862].
4.9. Recommended retransmission behavior
In situations where Neighbor Solicitation probes and Router
Solicitation probes are used on the same link, it is possible that
the NS probe will complete successfully, and then the RS probe will
complete later with a different result. If this happens, the
implementation SHOULD abandon the results obtained from the NS probe
of the router that responded to the RS and the implementation SHOULD
behave as if the NS probe did not successfully complete. If the
confirmed address was assigned manually, the implementation SHOULD
NOT unconfigure the manually assigned address and SHOULD log an error
about the mismatching prefix.
Where the NS probe does not complete successfully, it usually implies
that the host is not attached to the network whose configuration is
being tested. In such circumstances, there is typically little value
in aggressively retransmitting unicast neighbor solicitations that do
not elicit a response.
Where unicast Neighbor Solicitations and Router Solicitations are
sent in parallel, one strategy is to forsake retransmission of
Neighbor Solicitations and to allow retransmission only of Router
Solicitations or DHCPv6. In order to reduce competition between
unicast Neighbor Solicitations and Router Solicitations and DHCPv6
retransmissions, a DNAv6 implementation that retransmits may utilize
the retransmission strategy described in the DHCPv6 specification
[RFC3315], scheduling DNAv6 retransmissions between Router
Solicitation or DHCPv6 retransmissions.
If a response is received to any unicast Neighbor Solicitation,
Router Solicitation or DHCPv6 message, pending retransmissions MUST
be canceled [RFC3315][RFC3736]. A Simple DNA implementation SHOULD
NOT retransmit a Neighbor Solicitation more than twice. To provide
damping in the case of spurious Link Up indications, the host SHOULD
NOT perform the Simple DNA procedure more than once a second.
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5. Pseudocode for Simple DNA
/* Link up indication received on INTERFACE */
/* Start Simple DNA process */
/* Mark All Addresses as deprecated */
Configured_Address_List=Get_Address_List(INTERFACE);
foreach Configured_Address in Configured_Address_List
{
if (Get_Address_State(Configured_Address)!=AS_TENTATIVE)
{
Set_Address_State(Configured_Address,AS_DEPRECATED);
}
}
/* Mark all routers' NC entries as STALE to speed up */
/* acquisition of new router if link change has occurred */
foreach Router_Address in DEFAULT_ROUTER_LIST
{
NCEntry=Get_Neighbor_Cache_Entry(Router_Address);
Set_Neighbor_Cache_Entry_State(NCEntry,NCS_STALE);
}
/* Thread A : Send Router Solicitation */
RS_Target_Address=FF02::2;
RS_Source_Address=Get_Any_Link_Local_Address(INTERFACE);
Send_Router_Solicitation(RS_Source_Address,RS_Target_Address);
/* Thread B : Send Neighbor Solicitation(s) */
Previously_Known_Router_List=Get_Router_List_from_SDAT();
NS_Source_Address=Get_Any_Link_Local_Address(INTERFACE);
foreach Router_Address in Previously_Known_Router_List
{
if (Get_Any_Valid_Address_from_SDAT(Router_Address))
{
Send_Neighbor_Solicitation(NS_Source_Address,Router_Address);
}
}
/* Thread C : Response collection */
/* Received Router Advertisement processing */
/* Only for RAs received as response to DNA RSs */
L3_Source=Get_L3_Source(RECEIVED_MESSAGE);
L2_Source=Get_L2_Source(RECEIVED_MESSAGE);
SDAT_Entry_List=Get_Entries_from_SDAT_L2L3(L3_Source,L2_Source));
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foreach SDAT_Entry in SDAT_Entry_List
{
if (Exists_PIO(RECEIVED_MESSAGE,Get_Prefix(SDAT_Entry)))
{
/* Address is operable. Configure on Interface */
/* Rejoin solicited-node multicast group for address */
}
else
{
/* If address is configured on interface, remove it */
/* This could be because of a NA arriving before RA */
}
}
/* Mark router as reachable */
NCEntry=Get_Neighbor_Cache_Entry(L3_Source);
if (NCEntry is not NULL)
{
Set_Neighbor_Cache_Entry_State(NCEntry,NCS_REACHABLE);
}
else
{
Create_Neighbor_Cache_Entry(L3_Source,NCS_REACHABLE);
}
/* Ignore further NAs from this router */
Add_Router_to_NA_Ignore_List(L3_Source);
/* Received Neighbor Advertisement processing */
/* Only for NAs received as response to DNA NSs */
L3_Source=Get_L3_Source(RECEIVED_MESSAGE);
L2_Source=Get_L2_Source(RECEIVED_MESSAGE);
if (Is_Router_on_NA_Ignore_List(L3_Source)) {
/* Ignore message and wait for next message */
continue;
}
SDAT_Entry_List=Get_Entries_from_SDAT_L2L3(L3_Source,L2_Source));
foreach SDAT_Entry in SDAT_Entry_List
{
/* Address is operable. Configure on Interface */
}
Figure 1: Pseudocode for Simple DNA
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6. Constants
SEND_NA_GRACE_TIME
Definition: An optional period to wait after Neighbor
Solicitation before adopting a non-SEND RA's link change
information.
Value: 40 milliseconds
7. Relationship to DNAv4
DNAv4 [RFC4436] specifies a set of steps that optimize the (common)
case of re-attachment to an IPv4 network that one has been connected
to previously by attempting to re-use a previous (but still valid)
configuration. This document shares the same goal as DNAv4 (that of
minimizing the handover latency in moving between points of
attachment) but differs in the steps it performs to achieve this
goal. Another difference is that this document also supports
stateless autoconfiguration of addresses in addition to addresses
configured using DHCPv6.
8. IANA Considerations
There are no changes to IANA registries required in this document.
9. Security Considerations
A host may receive Router Advertisements from non-SEND devices, after
receiving a link-layer indications. While it is necessary to assess
quickly whether a host has moved to another network, it is important
that the host's current secured SEND [RFC3971] router information is
not replaced by an attacker which spoofs an RA and purports to change
the link.
As such, the host SHOULD send a Neighbor Solicitation to the existing
SEND router upon link-up indication as described above in
Section 4.3. The host SHOULD then ensure that unsecured router
information does not cause deletion of existing SEND state, within
MIN_DELAY_BETWEEN_RAS, in order to allow for a present SEND router to
respond.
If the current default router is a SEND-secured router, the host
SHOULD wait SEND_NA_GRACE_TIME after transmission before adopting a
new default router.
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Even if SEND signatures on RAs are used, it may not be immediately
clear if the router is authorized to make such advertisements. As
such, a host SHOULD NOT treat such devices as secure until and unless
authorization delegation discovery is successful.
10. Acknowledgments
This document is the product of a discussion the authors had with
Bernard Aboba, Thomas Narten, Erik Nordmark and Dave Thaler at IETF
69. The authors would like to thank them for clearly detailing the
requirements of the solution and the goals it needed to meet and for
helping to explore the solution space. The authors would like to
thank the authors and editors of the complete DNA specification for
detailing the overall problem space and solutions. The authors would
like to thank Jari Arkko for driving the evolution of a simple and
probabilistic DNA solution. The authors would like to thank Bernard
Aboba, Thomas Narten, Jari Arkko, Sathya Narayan, Julien Laganier,
Domagoj Premec, Jin Hyeock-Choi, Alfred Hoenes and Frederic Rossi for
performing reviews on the document and providing valuable comments to
drive the document forward.
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3736] Droms, R., "Stateless Dynamic Host Configuration Protocol
(DHCP) Service for IPv6", RFC 3736, April 2004.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure
Neighbor Discovery (SEND)", RFC 3971, March 2005.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.
11.2. Informative References
[I-D.ietf-dna-protocol]
Narayanan, S., "Detecting Network Attachment in IPv6
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Networks (DNAv6)", draft-ietf-dna-protocol (work in
progress), June 2007.
[RFC4957] Krishnan, S., Montavont, N., Njedjou, E., Veerepalli, S.,
and A. Yegin, "Link-Layer Event Notifications for
Detecting Network Attachments", RFC 4957, August 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[RFC4436] Aboba, B., Carlson, J., and S. Cheshire, "Detecting
Network Attachment in IPv4 (DNAv4)", RFC 4436, March 2006.
Appendix A. Issues with confirming manually assigned addresses
Even though DNAv4 [RFC4436] supports verification of manually
assigned addresses this feature of DNAv4 has not been widely
implemented or used. There are two major issues that come up with
confirming manually assigned addresses using Simple DNA.
o When DHCPv6 or SLAAC addresses are used for probing, there is no
need to aggressively retransmit lost probes. This is because the
address configuration falls back to vanilla DHCPv6 or SLAAC and
the host will eventually obtain an address. This is not the case
with manually assigned addresses. If the probes are lost, the
host runs the risk of ending up with no addresses at all. Hence
agressive retransmissions are mandated.
o Another issue comes up when the host moves between two networks,
one where manual addressing is being used (say NET1)and the other
where dynamic addressing (DHCPv6) is being used (say NET2). When
the host moves to NET1 from NET2 it tries to confirm both the
manual address and the dynamic address in parallel. If the probe
for the manually assigned address is lost, the DHCPv6 probe will
succeed and the host will incorrectly end up using the DHCPv6
assigned address (from NET2) on NET1.
Given these issues, it is NOT RECOMMENDED to use manual addressing
with Simple DNA.
Krishnan & Daley Expires March 20, 2010 [Page 16]
Internet-Draft Simple DNA September 2009
Authors' Addresses
Suresh Krishnan
Ericsson
8400 Decarie Blvd.
Town of Mount Royal, QC
Canada
Phone: +1 514 345 7900 x42871
Email: suresh.krishnan@ericsson.com
Greg Daley
NetStar Networks
Level 9/636 St Kilda Rd
Melbourne, Victoria 3004
Australia
Phone: +61 3 8532 4042
Email: gdaley@netstarnetworks.com
Krishnan & Daley Expires March 20, 2010 [Page 17]
