As per Relevance of the word addresses, we have this rfc below:
Network Working Group T.
Request for Comments: 3041
Category: Standards Track R.
Microsoft
January 2001
Privacy Extensions for Stateless Address Autoconfiguration in IPv
Status of this
This document specifies an Internet standards track protocol for
Internet community, and requests discussion and suggestions
improvements. Please refer to the current edition of the "
Official Protocol Standards" (STD 1) for the standardization
and status of this protocol. Distribution of this memo is unlimited
Copyright
Copyright (C) The Internet Society (2001). All Rights Reserved
Nodes use IPv6 stateless address autoconfiguration to
addresses without the necessity of a Dynamic Host
Protocol (DHCP) server. Addresses are formed by combining
prefixes with an interface identifier. On interfaces that
embedded IEEE Identifiers, the interface identifier is
derived from it. On other interface types, the interface
is generated through other means, for example, via random
generation. This document describes an extension to IPv6
address autoconfiguration for interfaces whose interface
is derived from an IEEE identifier. Use of the extension
nodes to generate global-scope addresses from interface
that change over time, even in cases where the interface contains
embedded IEEE identifier. Changing the interface identifier (and
global-scope addresses generated from it) over time makes it
difficult for eavesdroppers and other information collectors
identify when different addresses used in different
actually correspond to the same node
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RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
Table of
1. Introduction............................................. 2
2. Background............................................... 3
2.1. Extended Use of the Same Identifier................. 3
2.2. Address Usage in IPv4 Today......................... 4
2.3. The Concern With IPv6 Addresses..................... 5
2.4. Possible Approaches................................. 6
3. Protocol Description..................................... 7
3.1. Assumptions......................................... 8
3.2. Generation Of Randomized Interface Identifiers...... 9
3.3. Generating Temporary Addresses...................... 10
3.4. Expiration of Temporary Addresses................... 11
3.5. Regeneration of Randomized Interface Identifiers.... 12
4. Implications of Changing Interface Identifiers........... 13
5. Defined Constants........................................ 14
6. Future Work.............................................. 14
7. Security Considerations.................................. 15
8. Acknowledgments.......................................... 15
9. References............................................... 15
10. Authors' Addresses....................................... 16
11. Full Copyright Statement................................. 17
1.
Stateless address autoconfiguration [ADDRCONF] defines how an IPv
node generates addresses without the need for a DHCP server.
types of network interfaces come with an embedded IEEE
(i.e., a link-layer MAC address), and in those cases
address autoconfiguration uses the IEEE identifier to generate a 64-
bit interface identifier [ADDRARCH]. By design, the
identifier is likely to be globally unique when generated in
fashion. The interface identifier is in turn appended to a prefix
form a 128-bit IPv6 address
All nodes combine interface identifiers (whether derived from an
identifier or generated through some other technique) with
reserved link-local prefix to generate link-local addresses for
attached interfaces. Additional addresses, including site-local
global-scope addresses, are then created by combining
advertised in Router Advertisements via Neighbor
[DISCOVERY] with the interface identifier
Not all nodes and interfaces contain IEEE identifiers. In
cases, an interface identifier is generated through some other
(e.g., at random), and the resultant interface identifier is
globally unique and may also change over time. The focus of
document is on addresses derived from IEEE identifiers, as
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concern being addressed exists only in those cases where
interface identifier is globally unique and non-changing. The
of this document assumes that IEEE identifiers are being used,
the techniques described may also apply to interfaces with
types of globally unique and/or persistent identifiers
This document discusses concerns associated with the embedding
non-changing interface identifiers within IPv6 addresses
describes extensions to stateless address autoconfiguration that
help mitigate those concerns for individual users and in
where such concerns are significant. Section 2 provides
information on the issue. Section 3 describes a procedure
generating alternate interface identifiers and global-
addresses. Section 4 discusses implications of changing
identifiers
2.
This section discusses the problem in more detail, provides
for evaluating the significance of the concerns in
environments and makes comparisons with existing practices
2.1. Extended Use of the Same
The use of a non-changing interface identifier to form addresses is
specific instance of the more general case where a
identifier is reused over an extended period of time and in
independent activities. Anytime the same identifier is used
multiple contexts, it becomes possible for that identifier to be
to correlate seemingly unrelated activity. For example, a
sniffer placed strategically on a link across which all
to/from a particular host crosses could keep track of
destinations a node communicated with and at what times.
information can in some cases be used to infer things, such as
hours an employee was active, when someone is at home, etc
One of the requirements for correlating seemingly
activities is the use (and reuse) of an identifier that
recognizable over time within different contexts. IP
provide one obvious example, but there are more. Many nodes
have DNS names associated with their addresses, in which case the
name serves as a similar identifier. Although the DNS
associated with an address is more work to obtain (it may require
DNS query) the information is often readily available. In
cases, changing the address on a machine over time would do little
address the concerns raised in this document, unless the DNS name
changed as well (see Section 4).
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Web browsers and servers typically exchange "cookies" with each
[COOKIES]. Cookies allow web servers to correlate a current
with a previous activity. One common usage is to send back
advertising to a user by using the cookie supplied by the browser
identify what earlier queries had been made (e.g., for what type
information). Based on the earlier queries, advertisements can
targeted to match the (assumed) interests of the end-user
The use of a constant identifier within an address is of
concern because addresses are a fundamental requirement
communication and cannot easily be hidden from eavesdroppers
other parties. Even when higher layers encrypt their payloads
addresses in packet headers appear in the clear. Consequently, if
mobile host (e.g., laptop) accessed the network from
different locations, an eavesdropper might be able to track
movement of that mobile host from place to place, even if the
layer payloads were encrypted [SERIALNUM].
2.2. Address Usage in IPv4
Addresses used in today's Internet are often non-changing in
for extended periods of time, especially in non-home
(e.g., corporations, campuses, etc.). In such sites, addresses
assigned statically and typically change infrequently. Over the
few years, sites have begun moving away from static allocation
dynamic allocation via DHCP [DHCP]. In theory, the address a
gets via DHCP can change over time, but in practice servers
return the same address to the same client (unless addresses are
such short supply that they are reused immediately by a
node when they become free). Thus, even within sites using DHCP
clients frequently end up using the same address for weeks to
at a time
For home users accessing the Internet over dialup lines,
situation is generally different. Such users do not have
connections and are often assigned temporary addresses each time
connect to their ISP (e.g., AOL). Consequently, the addresses
use change frequently over time and are shared among a number
different users. Thus, an address does not reliably identify
particular device over time spans of more than a few minutes
A more interesting case concerns always-on connections (e.g.,
modems, ISDN, DSL, etc.) that result in a home site using the
address for extended periods of time. This is a scenario that
just starting to become common in IPv4 and promises to become more
a concern as always-on internet connectivity becomes
available. Although it might appear that changing an
regularly in such environments would be desirable to lessen
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concerns, it should be noted that the network prefix portion of
address also serves as a constant identifier. All nodes at (say)
home, would have the same network prefix, which identifies
topological location of those nodes. This has implications
privacy, though not at the same granularity as the concern that
document addresses. Specifically, all nodes within a home would
grouped together for the purposes of collecting information.
issue is difficult to address, because the routing prefix part of
address contains topology information and cannot contain
values
Finally, it should be noted that nodes that need a (non-changing)
name generally have static addresses assigned to them to simplify
configuration of DNS servers. Although Dynamic DNS [DDNS] can
used to update the DNS dynamically, it is not yet widely deployed
In addition, changing an address but keeping the same DNS name
not really address the underlying concern, since the DNS name
a non-changing identifier. Servers generally require a DNS name (
clients can connect to them), and clients often do as well (e.g.,
some servers refuse to speak to a client whose address cannot
mapped into a DNS name that also maps back into the same address).
Section 4 describes one approach to this issue
2.3. The Concern With IPv6
The division of IPv6 addresses into distinct topology and
identifier portions raises an issue new to IPv6 in that a
portion of an IPv6 address (i.e., the interface identifier)
contain an identifier that remains constant even when the
portion of an address changes (e.g., as the result of connecting to
different part of the Internet). In IPv4, when an address changes
the entire address (including the local part of the address)
changes. It is this new issue that this document addresses
If addresses are generated from an interface identifier, a
user's address could contain an interface identifier that remains
same from one dialup session to the next, even if the rest of
address changes. The way PPP is used today, however, PPP
typically unilaterally inform the client what address they are to
(i.e., the client doesn't generate one on its own). This practice
if continued in IPv6, would avoid the concerns that are the focus
this document
A more troubling case concerns mobile devices (e.g., laptops, PDAs
etc.) that move topologically within the Internet. Whenever
move (in the absence of technology such as mobile IP [MOBILEIP]),
they form new addresses for their current topological point
attachment. This is typified today by the "road warrior" who
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Internet connectivity both at home and at the office. While
node's address changes as it moves, however, the interface
contained within the address remains the same (when derived from
IEEE Identifier). In such cases, the interface identifier can
used to track the movement and usage of a particular
[SERIALNUM]. For example, a server that logs usage
together with a source addresses, is also recording the
identifier since it is embedded within an address. Consequently,
data-mining technique that correlates activity based on
could easily be extended to do the same using the
identifier. This is of particular concern with the
proliferation of next-generation network-connected devices (e.g.,
PDAs, cell phones, etc.) in which large numbers of devices are
practice associated with individual users (i.e., not shared). Thus
the interface identifier embedded within an address could be used
track activities of an individual, even as they move
within the internet
In summary, IPv6 addresses on a given interface generated
Stateless Autoconfiguration contain the same interface identifier
regardless of where within the Internet the device connects.
facilitates the tracking of individual devices (and thus
users). The purpose of this document is to define mechanisms
eliminate this issue, in those situations where it is a concern
2.4. Possible
One way to avoid some of the problems discussed above is to use
for obtaining addresses. With DHCP, the DHCP server could arrange
hand out addresses that change over time
Another approach, compatible with the stateless
autoconfiguration architecture, would be to change the interface
portion of an address over time and generate new addresses from
interface identifier for some address scopes. Changing the
identifier can make it more difficult to look at the IP addresses
independent transactions and identify which ones actually
to the same node, both in the case where the routing prefix
of an address changes and when it does not
Many machines function as both clients and servers. In such cases
the machine would need a DNS name for its use as a server.
the address stays fixed or changes has little privacy
since the DNS name remains constant and serves as a
identifier. When acting as a client (e.g.,
communication), however, such a machine may want to vary
addresses it uses. In such environments, one may need
addresses: a "public" (i.e., non-secret) server address,
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in the DNS, that is used to accept incoming connection requests
other machines, and a "temporary" address used to shield the
of the client when it initiates communication. These two cases
roughly analogous to telephone numbers and caller ID, where a
may list their telephone number in the public phone book, but
the display of its number via caller ID when initiating calls
To make it difficult to make educated guesses as to whether
different interface identifiers belong to the same node,
algorithm for generating alternate identifiers must include
that has an unpredictable component from the perspective of
outside entities that are collecting information.
identifiers from a pseudo-random sequence suffices, so long as
specific sequence cannot be determined by an outsider
information that is readily available or easily determinable (e.g.,
by examining packet contents). This document proposes the
of a pseudo-random sequence of interface identifiers via an MD5 hash
Periodically, the next interface identifier in the sequence
generated, a new set of temporary addresses is created, and
previous temporary addresses are deprecated to discourage
further use. The precise pseudo-random sequence depends on both
random component and the globally unique interface identifier (
available), to increase the likelihood that different nodes
different sequences
3. Protocol
The goal of this section is to define procedures that
1) Do not result in any changes to the basic behavior of
generated via stateless address autoconfiguration [ADDRCONF].
2) Create additional global-scope addresses based on a
interface identifier for use with global scope addresses.
addresses would be used to initiate outgoing sessions.
"random" or temporary addresses would be used for a short
of time (hours to days) and would then be deprecated.
address can continue to be used for already
connections, but are not used to initiate new connections.
temporary addresses are generated periodically to
temporary addresses that expire, with the exact time
address generation a matter of local policy
3) Produce a sequence of temporary global-scope addresses from
sequence of interface identifiers that appear to be random in
sense that it is difficult for an outside observer to predict
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RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
future address (or identifier) based on a current one and it
difficult to determine previous addresses (or identifiers)
only the present one
4) Generate a set of addresses from the same (randomized)
identifier, one address for each prefix for which a global
has been generated via stateless address autoconfiguration.
the same interface identifier to generate a set of
addresses reduces the number of IP multicast groups a host
join. Nodes join the solicited-node multicast address for
unicast address they support, and solicited-node addresses
dependent only on the low-order bits of the corresponding address
This decision was made to address the concern that a node
joins a large number of multicast groups may be required to
its interface into promiscuous mode, resulting in possible
performance
3.1.
The following algorithm assumes that each interface maintains
associated randomized interface identifier. When temporary
are generated, the current value of the associated
interface identifier is used. The actual value of the
changes over time as described below, but the same identifier can
used to generate more than one temporary address
The algorithm also assumes that for a given temporary address,
implementation can determine the corresponding public address
which it was generated. When a temporary address is deprecated,
new temporary address is generated. The specific valid and
lifetimes for the new address are dependent on the
lifetime values in the public address
Finally, this document assumes that when a node initiates
communication, temporary addresses can be given preference
public addresses. This can mean that all connections initiated
the node use temporary addresses by default, or that
individually indicate whether they prefer to use temporary or
addresses. Giving preference to temporary address is consistent
on-going work that addresses the topic of source-address selection
the more general case [ADDR_SELECT]. An implementation may make it
policy that it does not select a public address in the event that
temporary address is available (e.g., if generation of a
temporary address fails).
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3.2. Generation Of Randomized Interface Identifiers
We describe two approaches for the maintenance of the
interface identifier. The first assumes the presence of
storage that can be used to record state history for use as
into the next iteration of the algorithm across system restarts.
second approach addresses the case where stable storage
unavailable and there is a need to generate randomized
identifiers without previous state
3.2.1. When Stable Storage Is
The following algorithm assumes the presence of a 64-bit "
value" that is used as input in generating a randomized
identifier. The very first time the system boots (i.e., out-of-the
box), a random value should be generated using techniques that
ensure the initial value is hard to guess [RANDOM]. Whenever a
interface identifier is generated, a value generated by
computation is saved in the history value for the next iteration
the algorithm
A randomized interface identifier is created as follows
1) Take the history value from the previous iteration of
algorithm (or a random value if there is no previous value)
append to it the interface identifier generated as described
[ADDRARCH].
2) Compute the MD5 message digest [MD5] over the quantity created
the previous step
3) Take the left-most 64-bits of the MD5 digest and set bit 6 (
left-most bit is numbered 0) to zero. This creates an
identifier with the universal/local bit indicating
significance only. Save the generated identifier as
associated randomized interface identifier
4) Take the rightmost 64-bits of the MD5 digest computed in step 2)
and save them in stable storage as the history value to be used
the next iteration of the algorithm
MD5 was chosen for convenience, and because its particular
were adequate to produce the desired level of randomization. IPv
nodes are already required to implement MD5 as part of IPsec [IPSEC],
thus the code will already be present on IPv6 machines
In theory, generating successive randomized interface
using a history scheme as above has no advantages over
them at random. In practice, however, generating truly
numbers can be tricky. Use of a history value is intended to
the particular scenario where two nodes generate the same
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RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
interface identifier, both detect the situation via DAD, but
proceed to generate identical randomized interface identifiers
the same (flawed) random number generation algorithm. The
algorithm avoids this problem by having the interface
(which will often be globally unique) used in the calculation
generates subsequent randomized interface identifiers. Thus, if
nodes happen to generate the same randomized interface identifier
they should generate different ones on the followup attempt
3.2.2. In The Absence of Stable
In the absence of stable storage, no history value will be
across system restarts to generate a pseudo-random sequence
interface identifiers. Consequently, the initial history value
above will need to be generated at random. A number of
might be appropriate. Consult [RANDOM] for suggestions on
sources for obtaining random numbers. Note that even though
may not have stable storage for storing a history value, they will
many cases have configuration information that differs from
machine to another (e.g., user identity, security keys,
numbers, etc.). One approach to generating a random initial
value in such cases is to use the configuration information
generate some data bits (which may remain constant for the life
the machine, but will vary from one machine to another), append
random data and compute the MD5 digest as before
3.3. Generating Temporary
[ADDRCONF] describes the steps for generating a link-local
when an interface becomes enabled as well as the steps for
addresses for other scopes. This document extends [ADDRCONF]
follows. When processing a Router Advertisement with a
Information option carrying a global-scope prefix for the purposes
address autoconfiguration (i.e., the A bit is set), perform
following steps
1) Process the Prefix Information Option as defined in [ADDRCONF],
either creating a public address or adjusting the lifetimes
existing addresses, both public and temporary. When adjusting
lifetimes of an existing temporary address, only lower
lifetimes. Implementations must not increase the lifetimes of
existing temporary address when processing a Prefix
Option
2) When a new public address is created as described in [ADDRCONF
(because the prefix advertised does not match the prefix of
address already assigned to the interface, and the Valid
in the option is not zero), also create a new temporary address
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3) When creating a temporary address, the lifetime values are
from the corresponding public address as follows
- Its Valid Lifetime is the lower of the Valid Lifetime of
public address or TEMP_VALID_LIFETIME
- Its Preferred Lifetime is the lower of the Preferred
of the public address or TEMP_PREFERRED_LIFETIME -
DESYNC_FACTOR
A temporary address is created only if this calculated
Lifetime is greater than REGEN_ADVANCE time units. In particular
an implementation must not create a temporary address with a
Preferred Lifetime
4) New temporary addresses are created by appending the interface'
current randomized interface identifier to the prefix that
used to generate the corresponding public address. If by
the new temporary address is the same as an address
assigned to the interface, generate a new randomized
identifier and repeat this step
5) Perform duplicate address detection (DAD) on the
temporary address. If DAD indicates the address is already
use, generate a new randomized interface identifier as
in Section 3.2 above, and repeat the previous steps as
up to 5 times. If after 5 consecutive attempts no non-
address was generated, log a system error and give up
to generate temporary addresses for that interface
Note: because multiple temporary addresses are generated from
same associated randomized interface identifier, there is
benefit in running DAD on every temporary address. This
recommends that DAD be run on the first address generated from
given randomized identifier, but that DAD be skipped on
subsequent addresses generated from the same randomized
identifier
3.4. Expiration of Temporary
When a temporary address becomes deprecated, a new one should
generated. This is done by repeating the actions described
Section 3.3, starting at step 3). Note that, except for
transient period when a temporary address is being regenerated,
normal operation at most one temporary address corresponding to
public address should be in a non-deprecated state at any given time
Note that if a temporary address becomes deprecated as result
processing a Prefix Information Option with a zero
Lifetime, then a new temporary address must not be generated.
Prefix Information Option will also deprecate the
public address
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To insure that a preferred temporary address is always available,
new temporary address should be regenerated slightly before
predecessor is deprecated. This is to allow sufficient time to
race conditions in the case where generating a new temporary
is not instantaneous, such as when duplicate address detection
be run. It is recommended that an implementation start the
regeneration process REGEN_ADVANCE time units before a
address would actually be deprecated
As an optional optimization, an implementation may wish to remove
deprecated temporary address that is not in use by applications
upper-layers. For TCP connections, such information is available
control blocks. For UDP-based applications, it may be the case
only the applications have knowledge about what addresses
actually in use. Consequently, one may need to use heuristics
deciding when an address is no longer in use (e.g., the
TEMP_VALID_LIFETIME suggested above).
3.5. Regeneration of Randomized Interface
The frequency at which temporary addresses should change depends
how a device is being used (e.g., how frequently it initiates
communication) and the concerns of the end user. The most
privacy concerns appear to involve addresses used for long periods
time (weeks to months to years). The more frequently an
changes, the less feasible collecting or coordinating
keyed on interface identifiers becomes. Moreover, the cost
collecting information and attempting to correlate it based
interface identifiers will only be justified if enough
contain non-changing identifiers to make it worthwhile. Thus,
large numbers of clients change their address on a daily or
basis is likely to be sufficient to alleviate most privacy concerns
There are also client costs associated with having a large number
addresses associated with a node (e.g., in doing address lookups,
need to join many multicast groups, etc.). Thus, changing
frequently (e.g., every few minutes) may have
implications
This document recommends that implementations generate new
addresses on a periodic basis. This can be achieved automatically
generating a new randomized interface identifier at least once
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR) time units
As described above, generating a new temporary address REGEN_
time units before a temporary address becomes deprecated
addresses with a preferred lifetime no larger
TEMP_PREFERRED_LIFETIME. The value DESYNC_FACTOR is a random
(different for each client) that ensures that clients don'
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synchronize with each other and generate new addresses at exactly
same time. When the preferred lifetime expires, a new
address is generated using the new randomized interface identifier
Because the precise frequency at which it is appropriate to
new addresses varies from one environment to another,
should provide end users with the ability to change the frequency
which addresses are regenerated. The default value is given
TEMP_PREFERRED_LIFETIME and is one day. In addition, the exact
at which to invalidate a temporary address depends on
applications are used by end users. Thus the default value given
one week (TEMP_VALID_LIFETIME) may not be appropriate in
environments. Implementations should provide end users with
ability to override both of these default values
Finally, when an interface connects to a new link, a new
interface identifier should be generated immediately together with
new set of temporary addresses. If a device moves from one
to another, generating a new set of temporary addresses from
different randomized interface identifier ensures that the
uses different randomized interface identifiers for the
addresses associated with the two links, making it more difficult
correlate addresses from the two different links as being from
same node
4. Implications of Changing Interface
The IPv6 addressing architecture goes to some lengths to ensure
interface identifiers are likely to be globally unique where easy
do so. During the IPng discussions of the GSE proposal [GSE], it
felt that keeping interface identifiers globally unique in
might prove useful to future transport protocols. Usage of
algorithms in this document may complicate providing such a
flexibility
The desires of protecting individual privacy vs. the desire
effectively maintain and debug a network can conflict with
other. Having clients use addresses that change over time will
it more difficult to track down and isolate operational problems
For example, when looking at packet traces, it could become
difficult to determine whether one is seeing behavior caused by
single errant machine, or by a number of them
Some servers refuse to grant access to clients for which no DNS
exists. That is, they perform a DNS PTR query to determine the
name, and may then also perform an A query on the returned name
verify that the returned DNS name maps back into the address
used. Consequently, clients not properly registered in the DNS
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RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
be unable to access some services. As noted earlier, however,
node's DNS name (if non-changing) serves as a constant identifier
The wide deployment of the extension described in this document
challenge the practice of inverse-DNS-based "authentication,"
has little validity, though it is widely implemented. In order
meet server challenges, nodes could register temporary addresses
the DNS using random names (for example a string version of
random address itself).
Use of the extensions defined in this document may
debugging and other operational troubleshooting activities
Consequently, it may be site policy that temporary addresses
not be used. Implementations may provide a method for a
administrator to override the use of temporary addresses
5. Defined
Constants defined in this document include
TEMP_VALID_LIFETIME -- Default value: 1 week. Users should be
to override the default value
TEMP_PREFERRED_LIFETIME -- Default value: 1 day. Users should
able to override the default value
REGEN_ADVANCE -- 5
MAX_DESYNC_FACTOR -- 10 minutes. Upper bound on DESYNC_FACTOR
DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR
It is computed once at system start (rather than each
it is used) and must never be greater
(TEMP_VALID_LIFETIME - REGEN_ADVANCE).
6. Future
An implementation might want to keep track of which addresses
being used by upper layers so as to be able to remove a
temporary address from internal data structures once no upper
protocols are using it (but not before). This is in contrast
current approaches where addresses are removed from an interface
they become invalid [ADDRCONF], independent of whether or not
layer protocols are still using them. For TCP connections,
information is available in control blocks. For UDP-
applications, it may be the case that only the applications
knowledge about what addresses are actually in use. Consequently,
implementation generally will need to use heuristics in deciding
an address is no longer in use (e.g., as is suggested in
3.4).
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The determination as to whether to use public vs. temporary
can in some cases only be made by an application. For example,
applications may always want to use temporary addresses, while
may want to use them only in some circumstances or not at all
Suitable API extensions will likely need to be developed to
individual applications to indicate with sufficient granularity
needs with regards to the use of temporary addresses
7. Security
The motivation for this document stems from privacy concerns
individuals. This document does not appear to add any
issues beyond those already associated with stateless
autoconfiguration [ADDRCONF].
8.
The authors would like to acknowledge the contributions of the
working group and, in particular, Matt Crawford, Steve Deering
Allison Mankin for their detailed comments
9.
[ADDRARCH] Hinden, R. and S. Deering, "IP Version 6
Architecture", RFC 2373, July 1998.
[ADDRCONF] Thomson, S. and T. Narten, "IPv6
Autoconfiguration", RFC 2462, December 1998.
[ADDR_SELECT] Draves, R. "Default Address Selection for IPv6",
in Progress
[COOKIES] Kristol, D. and L. Montulli, "HTTP State
Mechanism", RFC 2965, October 2000.
[DHCP] Droms, R., "Dynamic Host Configuration Protocol",
2131, March 1997.
[DDNS] Vixie, R., Thomson, S., Rekhter, Y. and J. Bound
"Dynamic Updates in the Domain Name System (
UPDATE)", RFC 2136, April 1997.
[DISCOVERY] Narten, T., Nordmark, E. and W. Simpson, "
Discovery for IP Version 6 (IPv6)", RFC 2461,
1998.
Narten & Draves Standards Track [Page 15]
RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
[GSE] Crawford, et al., "Separating Identifiers and
in Addresses: An Analysis of the GSE Proposal
IPv6", Work in Progress
[IPSEC] Kent, S., Atkinson, R., "Security Architecture for
Internet Protocol", RFC 2401, November 1998.
[MD5] Rivest, R., "The MD5 Message-Digest Algorithm",
1321, April 1992.
[MOBILEIP] Perkins, C., "IP Mobility Support", RFC 2002,
1996.
[RANDOM] Eastlake 3rd, D., Crocker S. and J. Schiller
"Randomness Recommendations for Security", RFC 1750,
December 1994.
[SERIALNUM] Moore, K., "Privacy Considerations for the Use
Hardware Serial Numbers in End-to-End
Protocols", Work in Progress
10. Authors'
Thomas
IBM
P.O. Box 12195
Research Triangle Park, NC 27709-2195
Phone: +1 919 254 7798
EMail: narten@raleigh.ibm.
Richard
Microsoft
One Microsoft
Redmond, WA 98052
Phone: +1 425 936 2268
EMail: richdr@microsoft.
Narten & Draves Standards Track [Page 16]
RFC 3041 Extensions to IPv6 Address Autoconfiguration January 2001
11. Full Copyright
Copyright (C) The Internet Society (2001). All Rights Reserved
This document and translations of it may be copied and furnished
others, and derivative works that comment on or otherwise explain
or assist in its implementation may be prepared, copied,
and distributed, in whole or in part, without restriction of
kind, provided that the above copyright notice and this paragraph
included on all such copies and derivative works. However,
document itself may not be modified in any way, such as by
the copyright notice or references to the Internet Society or
Internet organizations, except as needed for the purpose
developing Internet standards in which case the procedures
copyrights defined in the Internet Standards process must
followed, or as required to translate it into languages other
English
The limited permissions granted above are perpetual and will not
revoked by the Internet Society or its successors or assigns
This document and the information contained herein is provided on
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
Funding for the RFC Editor function is currently provided by
Internet Society
Narten & Draves Standards Track [Page 17]
if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.
RFC documents can be found at I.E.T.F.
Relevance System Copyright © 2002 Spectrum WorldResearch
other technical nosh by ServerMasters Corporation
collaboration of BobX
