IPv6 maintenance Working Group (6man) H. Rafiee
INTERNET-DRAFT C. Meinel
Updates RFC 3971 , RFC 3972, RFC 4941 Hasso Plattner Institute
(if approved)
Intended status: Standard Track
Expires: August 25, 2013 February 25, 2013
A Simple Secure Addressing Generation Scheme for IPv6 AutoConfiguration
(SSAS)
<draft-rafiee-6man-ssas-02.txt>
Abstract
The default method for IPv6 address generation uses an
Organizationally Unique Identifier (OUI) assigned by the IEEE
Standards Association and an Extension Identifier assigned to the
hardware manufacturer [1] (section 2.5.1 RFC-4291) [RFC4291]. This
means that a node will always have the same Interface ID (IID)
whenever it connects to a new network. Since the node's IP address
does not change, the node is vulnerable to privacy related attacks.
To address this problem there are currently two mechanisms being used
to randomize the IID that do not use the MAC address or other unique
values in the IID generation; Cryptographically Generated Addresses
(CGA) [RFC3972] and Privacy Extension [RFC4941]. The problem with the
former approach is the computational cost involved for the IID
generation and verification. The problem with the latter approach is
that it lacks the necessary security and provides the node with only
partial protection against privacy related attacks. This document
proposes the use of a new algorithm for use in the generation of the
IID while, at the same time, securing the node against some types of
attack, like IP spoofing. These attacks are prevented with the
addition of a signature to the messages sent over the network and by
direct use of a public key in the IP address.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute working
documents as Internet-Drafts. The list of current Internet-Drafts is
at http://datatracker.ietf.org/drafts/current.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 21, 2013.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. This document is subject to
BCP 78 and the IETF Trust's Legal Provisions Relating to IETF
Documents (http://trustee.ietf.org/license-info) in effect on the
date of publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Conventions used in this document . . . . . . . . . . . . . . 3
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 4
2.1. SSAS Applications . . . . . . . . . . . . . . . . . . . . 5
2.1.1. Preventing Attacks . . . . . . . . . . . . . . . . . 5
2.1.1.1. Replay attack . . . . . . . . . . . . . . . . . . 5
2.1.1.2. IP spoofing . . . . . . . . . . . . . . . . . . . 5
2.1.1.3. Denial of Service (DoS) attacks . . . . . . . . . 5
2.1.1.4. Spoofed Redirect Message . . . . . . . . . . . . 6
2.1.2. Nodes with limited resources . . . . . . . . . . . . 6
3. Algorithm Overview . . . . . . . . . . . . . . . . . . . . . 6
3.1. Interface ID (IID) Generation . . . . . . . . . . . . . . 6
3.2. Signature Generation . . . . . . . . . . . . . . . . . . 9
3.3. Generation of NDP Messages . . . . . . . . . . . . . . . 9
3.3.1. SSAS signature data field . . . . . . . . . . . . . . 10
3.4. SSAS verification process . . . . . . . . . . . . . . . . 11
4. Security Considerations . . . . . . . . . . . . . . . . . . . 12
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
6. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . 13
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
7.1. Normative . . . . . . . . . . . . . . . . . . . . . . . . 14
7.2. Informative . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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Introduction
IPv6 addresses consist of two parts; the subnet prefix, which is the
64 leftmost bits of the IPv6 address, and the Interface ID (IID),
which is the 64 rightmost bits of the IPv6 address. The IEEE
Standards Association [1] (section 2.5.1 RFC-4291) [RFC4291] offered
a standard for the generation of the IPv6 Interface IDs (IID) which
it called the Extended Unique Identifier (EUI-64). EUI-64s are
generated by the concatenation of an Organizationally Unique
Identifier (OUI) assigned by the IEEE Registration Authority (IEEE
RA) with the Extension Identifier assigned by the hardware
manufacturer. For example, if a manufacturer's OUI-36 hexadecimal
value is 00-5A-D1-02-3, and the manufacture hexadecimal value, for
the Extension Identifier for a given component, is 4-42-61-71, then
the EUI-64 value generated from these two numbers will be
00-5A-D1-02-34-42-61-71. If the OUI is 24 bits and the extension
identifier is also 24 bits (this constitutes the MAC address), then
to form the 64-bit EUI address, the OUI portion of the MAC address is
inserted into the leftmost 24 bits of the EUI-64 8 byte field and the
Extension Identifier is inserted into the rightmost 24 bits of the
EUI-64 8 byte field, and then a value of 0xFFFE is inserted between
these two 24-bit items. IEEE has chosen 0xFFFE as a reserved value
which can only appear in an EUI-64 generated from an EUI-48 MAC
address. Then bit 7 (u bit) in the OUI portion of the address should
be set. Globally unique addresses assigned by the IEEE set this bit
to zero by default indicating global uniqueness.This bit will be set
to 1 for locally created addresses, such as those used for virtual
interfaces or a MAC address manually configured by an administrator.
There are two mechanisms used to generate a randomized IID that do
not make use of a MAC address; CGA [RFC3972] and Privacy Extension
[RFC4941]. In this document we discuss the problem inherent with
using the current mechanisms and then we explain our solution to the
problem, which is to randomize the IID and observing privacy, while,
at the same time, providing security to Neighbor Discovery Protocol
(NDP) messages, for nodes, in the IP layer. DHCPv6 [RFC3315] can also
benefit from this approach for the generation of a random IID or for
authentication purposes.
1. Conventions used in this document
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 RFC-2119 [RFC2119].
In this document, these words will appear with that interpretation
only when in ALL CAPS. Lower case uses of these words are not to be
interpreted as carrying RFC-2119 significance.
In this document the use of || indicates the concatenation of the
values on either side of the sign.
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2. Problem Statement
The drawback to using IIDs that do not change over time is one of
privacy. The node will generate the same IID whenever it joins a new
network thus making it easy for an attacker to track that node when
it moves to different networks.
The main problem with the privacy extension mechanism, when using the
first approach as explained in section 3.2.1 RFC-4941 [RFC4941],
i.e., using stable storage, is the lack of a provision for the use of
a security mechanism. The Privacy Extension RFC can partly prevent
attacks related to privacy issues, but it cannot prevent attacks
related to security issues. For instance, it cannot prevent IP
spoofing attacks and it cannot provide proof of the IP address
ownership of a node. If one wants to use a secure method, with the
privacy extension, then one needs to use CGA. The problem with using
CGA is in the computational overhead necessary to compute it when a
higher sec value is used and the time that is needed in the
verification process. This time is based on the reverse of the steps
required to regenerate CGA during the verification process, in
addition to the signature verification.
What is clear here is that it is not possible to generate the CGA
offline or before hand. This is because the subnet prefix (router
prefix) is one of the inputs to the SHA1 algorithm. The other problem
with CGA is the apparent lack of a defense against Denial of Service
(DoS) types of attack against verifier nodes. In the CGA RFC, there
is no explanation as to how to prevent these types of attacks. This
means that an attacker can overwhelm the verifier node with false CGA
values thus rendering it unable to process further messages.This
document also proposes a solution for this type of attack.
To overcome the problem with using the other mechanisms the time
needed for IP address generation and verification needs to be
reduced. We propose the use of the SSAS algorithm, along with the
SSAS signature, to provide a node with the protection it needs to
protect it against IP spoofing and spoofing types of attack in the IP
layer. Our experimental results [2] show that SSAS is 5 times faster
than CGA, when using a sec value of ,0 and 600 times faster than CGA
when using the sec value of 1. This will be the same when, in the
future, we have faster CPUs because SSAS will also benefit from the
future technologies. Currently the generation time for SSAS is less
than 1 millisecond so with future new technologies it will be even
less.
Note: It is not the intent of this document to obsolete CGA but to
propose a simpler and a faster addressing mechanism to use in the
randomization of the IID and the for the protection of nodes against
the attacks explained below.
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2.1. SSAS Applications
2.1.1. Preventing Attacks
The following sections detail some of the attacks that SSAS can
prevent.
2.1.1.1. Replay attack
In this type of attack, an attacker might sniff the Neighbor
Discovery Protocol enabled networks (NDP) messages and try to copy
the legitimate signature and public key to his NDP message and then
send this to the sender. But by using the SSAS algorithm, this is
prevented with the addition of a timestamp to the NDP message and
also with inclusion of this timestamp in the signature. The use of
the timestamp works because the timestamp will be valid for a short
period of time. (this accounts for clock skews.)
2.1.1.2. IP spoofing
This is a well-known type of attack in NDP. This type of attack is
used to attack the Duplicate Address Detection process. In this
attack, when a node joins the network and generates a new IP address,
the node sends a Neighbor Solicitation (NS) message to check for
address collisions in the network. The attacker, in this scenario,
spoofs the IP address and responds back to the node with a Neighbor
Advertisement (NA) message claiming ownership of this IP address. The
SSAS algorithm allows this node to verify other nodes in the network.
An attacker does not have the private key for this node, which is
needed to generate a SSAS signature, so the verification process will
fail.
2.1.1.3. Denial of Service (DoS) attacks
An attacker might send many NDP messages, using invalid signatures,
to the victim?s node which then forces the node to busy itself with
the verification process. To mitigate this attack, a node SHOULD set
a limit on the number of messages (x) that the it can verify, per a
certain period of time. Implementations MUST provide a conservative
default and SHOULD provide a way for detecting when this limit is
reached.
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2.1.1.4. Spoofed Redirect Message
Redirect messages, imitating the end host needing redirection, can be
sent from any router on the same broadcast segment. The attacker uses
the link-local address of the current first-hop router in order to
send a Redirect message to a legitimate node. Since that node
identifies the message as coming from its first hop router, by use of
the link-local address, it accepts the Redirect. The Redirect will
remain in effect as long as the attacker responds to the Neighbor
Unreachability Detection probes sent to the link-layer address. To
preclude this from occurring, the address ownership of the first-hop
router should be verified. The use of the SSAS verification process
will prevent such an attack.
2.1.2. Nodes with limited resources
SSAS can be used in nodes where limited resources are available for
computation. It can provide protection for these nodes against the
attacks stated above. Sensor networks are examples of nodes with
limited resources (such as battery, CPU, and etc); see RFC-4919
[RFC4919] for the usage of IPv6 in these networks.
Another example could be the use of SSAS in mobile networks during
the generation of IP addresses as explained in section 4.4 RFC-6275.
The current problem with addressing mechanism in mobile node is that
there is no privacy observation as the node usually keeps its Home
Address when it moves to another network. If there is a fast secure
mechanism, then it is possible set this Home Address and change it
and re-register it to the Home network.
3. Algorithm Overview
As explained earlier, one of the problems with the current IID
generation approach is the compute intensive processing needed for
the IID algorithm generation. Another concern is the lack of
security. Since, we assume that a node needs to generate and keep its
address for a short time, we tried to keep the IID generation process
to a minimum. We also tried to remain within the confines of NDP
protocol.
3.1. Interface ID (IID) Generation
To generate the IID, a node needs to execute the following steps.
1. Generate a 16 byte random number called modifier.
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2. Generate a 1024-bit key pair (public/private key). These keys
SHOULD be stored in a safe place on a local hard disk and the path to
this data, and the validation time for these keys, SHOULD be saved in
a XML file. It is RECOMMENDED that the public key be generated, on
the fly, during the start-up phase of the algorithm generation.
Once a node generates key pairs, it can make use of these keys for a
short period of time. It is RECOMMENDED not to use the same keys for
more than 10 days in order to prevent the node from being tracked
through the use of its public keys. When time expires for the use of
these key pairs, the node should generate new key pairs and replace
the old one in the XML file. It SHOULD then use the new value for IP
address and signature generation.
It is also possible to use ECC [3] with a 192 bit key size. This is
equivalent to a1280 bit RSA key size. In this case the packet size
would be decreased by a factor 5 times smaller than when using RSA.
However, with key sizes 1024 bit and 1280 bit, RSA generation and
verification is much faster than ECC. The other problem with the use
of ECC is that it could be patented and might not be royalty free.
3. Concatenate the modifier with the timestamp and the public key.
The timestamp is a 64-bit unsigned integer field containing a
timestamp. The value indicates the number of seconds since January 1,
1970, 00:00 UTC, by using a fixed point format. The format of the
timestamp data field is the same as that outlined in section 5.3.1
RFC-3971 [RFC3971].
R1=(modifier(16 bytes)||timestamp(8 bytes)||public key)
4. Execute SHA2 (256) on the result from step 3.
digest=SHA256(R1)
The use of SHA2 (256) is RECOMMENDED because the chances of finding a
collision are less than when using SHA1 and the generation time is
acceptable (in microseconds using a standard CPU).
5. Generate a random number between 0 and 20 and call it the start
index. This number is used as an index for the SHA2 array of bytes.
This value helps randomize the IID and to minimize the chance of a
collision in the network. The length of this number is one byte.
6. Take the 32 leftmost bits (starting at the start index) from the
resulting output from step 5 (SHA2 digest) and set bits u and g (bits
7 and 8) and call this the partial IID.
+-------------------------------------+
| | partial IID | |
| | (32 bits) | |
+ +---------------+ +
| SHA2 digest |
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| (256 bits) |
+-------------------------------------+
Figure 1 Partial Interface ID
7. Obtain the second byte of the partial IID and call it the start
field pubkey. If the value of the start field pubkey is between 0 and
the size of public key length, in bytes, minus 4, use this number as
an index for the public key array of bytes. Otherwise choose that
byte and shift its contents 2 bits to the right (the first two bits
will be zero) and set the start field pubkey to this number. This
ensures that the value of the start field pubkey will be less than
the size of the public key array of bytes, minus 4. This value helps
randomize the IID and minimize the chance of a collision in the
network. For example, if the second byte of partial IID is 110, the
start field pubkey value will be 110. This value helps randomize the
IID and minimize the chance of a collision in the network. For
example, if the second byte of the partial IID is 110, then the start
field pubkey value will be 110.
If ECC is used for key generation, then the content of the start
field pubkey SHOULD be shifted 3 bits to the right. This insures that
its value is less than the size of public key array of bytes, minus
4.
+-------------------------------------+
| | Pubkey | |
| | (32 bits) | |
+ +---------------+ +
| Public key |
| (1024 bits) |
+-------------------------------------+
Figure 2 Public key part of Interface ID
8. Concatenate the partial IID with the four bytes from the public
key (starting at the start field pubkey) and call this the IID.
+-------------------+------------------+
| Partial IID | Pubkey |
| (32 bits) | (32 bits) |
+-------------------+------------------+
Figure 3 Interface ID
9. Concatenate the IID with the local subnet prefix to set the local
IP address
10. Concatenate the IID with the router subnet prefix (Global subnet
prefix), obtained from the RA message, and set it as a tentative
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global IP address. (This IP will be permanent after Duplicate Address
Detection (DAD) processing. (for more information about DAD refer to
section 4.3. )
3.2. Signature Generation
The SSAS signature is added to NDP messages in order to protect them
from IP spoofing and spoofing types of attack. SSAS will prove IP
address ownership, as does the CGA generation algorithm, but using
fewer steps. To generate the SSAS signature, the node needs to
execute the following steps:
1. Concatenate the timestamp with the 16 byte public key (that starts
at the start field pubkey) (see figure 4) and the global IP address.
The start field pubkey is one of the numbers that was introduced in
step 7 of section 4.1.
2. Sign the resulting value from step 1, using the RSA private key
unless we use ECC, and call the resulting output the SSAS signature.
+---------+----------+-----------------+-------------+
|timestamp|Public key|Global IP Address|Other Options|
|(8 bytes)|(16 bytes)| (16 bytes) | (variable) |
+---------+----------+-----------------+-------------+
Figure 4 SSAS Signature
If NDP messages contain other data that must be protected, such as
important routing information, this data SHOULD also be included in
the signature. The signature is designed for the inclusion of any
data needing protection. If there is no data that needs protection,
then the signature will only contain the timestamp, 16 byte public
key and Global IP address (Router subnet prefix plus IID).
3.3. Generation of NDP Messages
After a node generates its IP address, it should then process
Duplicate Address Detection in order to avoid address collisions in
the network. To do this, the node generates a Neighbor Solicitation
(NS) message. The format of a NS message is shown in figure 5. The
SSAS signature is added to the ICMPv6 options of NS messages. The
SSAS signature data field is an extended version of the standard
format of the RSA signature option of SEND [RFC3971]. The timestamp
option is the same as that used with SEND. In the SSAS signature, the
data field contains type, length, reserved, Other Len, pubkey len,
public key, SSAS signature, and padding.
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+----------------+-------------+----------------------------+
| IPv6 Header |ICMPv6 header| ND message Specific Data |
| Next header= 58| | (variable) |
+--------------+-+-----------+-+----------------------------+
| Type = 13 | length | Reserved |
| (1 byte) | (1 byte) | (6 bytes) |
+--------------+-------------+------------------------------+
| timestamp |
| |
+--------------+-------------+-------------+----------------+
| Type = 12 | length | Reserved | Other Len |
| (1 byte) | (1 byte) | (2 bytes) | (1 byte) |
+--------------+-+-----------+-----+-------+----------------+
| Subnet Prefix | Pubkey Len | Public Key in base64 |
| (8 byte) | (1 byte) | format |
+----------------+-----------------+------------------------+
| Other Options |
| |
+-----------------------------------------------------------+
| SSAS Signature |
| |
+-----------------------------------------------------------+
| padding |
| |
+-----------------------------------------------------------+
Figure 5 NDP Message Format with SSAS Signature Data Field
This document proposes an update to the SEND RFC in order to replace
the RSA signature field with the SSAS signature data field and to add
SSAS as a new option to SEND messages.
3.3.1. SSAS signature data field
- Type: This option should be set to 12.
- Length: The length of the Signature Data field, including the Type,
Length, Reserved, pubkey Len, public key, Signature and padding,
should be a multiple of eight.
- Reserved: A 2 byte field reserved for future use. The value MUST be
initialized to zero by the sender, and MUST be ignored by the
receiver.
- Other Len: The length of other options in multiples of eight. The
length of this is 1 byte.
- Subnet Prefix: This is the router subnet prefix.
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- PubKey Len. The length of the public key in multiples of eight.
- Public key. Base64 format of the public key
- Other Options. This variable-length field contains important data
that needs to be protected in the packet . The padding would be
added, as many bytes long as remain after the end of the field, if
the Other options is not a multiple of eight.
- Padding. This variable-length field contains padding, as many bytes
long as remain after the end of the signature, if the signature is
not a multiple of eight.
All NDP messages should contain the SSAS signature data field which
allows receivers to verify senders. If a node receives a solicited NA
message in response to its NS message showing that another node
claims to own this address, then, after a successful verification
process, this node increments the modifier by one and again repeats
steps 3 thru 8 of section 4.1 . If, for a second time, the node
receives the same claim, then it considers it an attack and will use
that IP address.
3.4. SSAS verification process
A node's verification process should start when it receives NDP
messages.
Following are the verification steps:
1. Obtain the timestamp from the NDP message and call this value t1.
2. Obtain the timestamp from the node's system, convert it to UTC,
and call this value t2.
3. If (t2- x) < = t1 < = (t2 + x) go to stop 4. Otherwise, the
message SHOULD be discarded without further processing. (The value of
x is dependent on network delays and network policy. One might
choose10 minutes (600 seconds) as a flexible way of handling network
delays.)
4. Obtain the public key from the SSAS signature data field.
5. Compare this to its own public key. If it is not the same, go to
the next step. Otherwise, the message should be discarded without
further processing.
6. Obtain the second byte of the partial IID and call it the start
field pubkey. If the value of the start field pubkey is between 0 and
the size of public key length, in bytes, minus 4, use this number as
an index for the public key array of bytes. Otherwise choose that
byte and shift its contents 2 bits to the right (the first two bits
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will be zero) and consider this number the starting index of the
public key array of bytes. This ensures that the value of that byte
will be less than the size of the public key array of bytes, minus 4.
Set the start field pubkey to this number.
If ECC is used for key generation, then the content of the start
field pubkey SHOULD be shifted 3 bits to the right. This insures that
its value is less than the size of public key array of bytes, minus
4.
7. Obtain the IID from the sender?s source IP address. (64 rightmost
bits of the IPv6 address)
8. Compare the 32 leftmost bits, starting at the start field pubkey
of the public key, to the 32 rightmost bits of the IID of the
sender?s IP address. If they are the same, go to the next step.
Otherwise, the message should be discarded without further processing
9. Obtain the subnet prefix from the SSAS signature data field.
10. Concatenate the timestamp with the 16 bytes of the public key,
(starting from start field pubkey), the subnet prefix, the sender?s
IID, and other options (if any) and call this entity the plain
message.
11. Obtain the SSAS signature from the SSAS signature data field.
12. Verify the Signature using the public key, and then enter the
plain message and the SSAS signature as an input to the verification
function. If the verification process is successful, process the
message. Otherwise, the message should be discarded without further
processing.
4. Security Considerations
As a security consideration what one might ask is what are the odds
of an attacker being able to generate a public key having four
sequential bytes the same as the last rightmost 32 bits of the IID If
he could, he could then generate the signature using his own private
key and thus break the SSAS.
Mathematically it has been shown that the probability of matching 32
bits in the public key against 32 bits in the IID is about
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pow(1/2,32) where pow is the power function, 2 is a base and 32 is a
exponent. Since the use of a public key and IP address with a maximum
lifetime of 10 days is RECOMMENDED, the probability of an attacker
finding the same value is 0.0008, a very small value. When one also
considers the probability of an attacker being able to generate a
public key whose 32 bits, starting from an arbitrary point, matches
the 32 bits of the public key generated using the SSAS algorithm,
then the probability of his success is diminished even further. This
shows the strength of this algorithm against brute force attacks
while, at the same time, by using the signature and finding a binding
between the IP address and the public key, it provides proof of IP
address ownership at a speed that is about 600 times faster than that
of the CGA algorithm [2]. (based on the implementation results, the
average time to generate SSAS is 882.77 microseconds).
Another consideration concerns Routers wanting to use this algorithm
in place of CGA. As explained in RFC SEND, for routers, the use of a
Trusted Authority is RECOMMENDED along with verifying router
certificates using these third parties. This will prevent a node from
claiming to be a router. But for nodes, rather than routers, SSAS can
provide protection against the types of attacks explained above.
5. IANA Considerations
This document defines a new algorithm for the generation of an
Interface ID in IPv6 networks.
6. Conclusions
Privacy has become a very important issue in recent years. A solution
for preventing a node from being tracked by an attacker is to change
the node's IP address frequently and by generating a random IID each
time a node wants to generate a new IP address. There are two
solutions available for randomizing the IID; CGA and Privacy
Extension. The former algorithm is compute intensive and the latter
algorithm is lacking in security. This document introduced a new
algorithm as a solution for providing privacy by randomizing the IID
and for providing security with the addition of a SSAS signature to
the NDP message and finding a binding between the public key and the
IP address. Our experimental results [2] show a definite improvement
in the computation time for the SSAS algorithm as compared to that
for the CGA algorithm. We also note that the probability of having
collisions with IP addresses, when using the SHA2 digest and the
public key, with a randomized 62 bit selection, approximates
pow(1/2,62) where pow is the power function, 2 is a base and 62 is a
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INTERNET DRAFT SSAS for Autoconfiguration February 25, 2013
exponent (u and g bits are ignored) . Moreover, the probability of an
attacker finding the public key which matches 32 rightmost bits of
the IID within 10 days approximates 0.0008. This means this algorithm
is secure enough for wide usage.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to
Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4291] Hinden, R., Deering, S., "IP Version 6 Addressing
Architecture," RFC 4291, February 2006.
[RFC3972] Aura, T., "Cryptographically Generated Addresses
(CGA)," RFC 3972, March 2005.
[RFC4941] Narten, T., Draves, R., Krishnan, S., "Privacy
Extensions for Stateless Address Autoconfiguration in
IPv6", RFC 4941, September 2007.
[RFC3971] Arkko, J., Kempf, J., Zill, B., and Nikander, P.,
"SEcure Neighbor Discovery (SEND)", RFC 3971, March 2005.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T.,
Perkins, C., Carney, M. , " Dynamic Host Configuration
Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC4919] Kushalnagar, N., Montenegro, G., Schumacher, C.,"
IPv6 over Low-Power Wireless Personal Area Networks
(6LoWPANs): Overview, Assumptions, Problem Statement, and
Goals", RFC 4919, August 2007.
7.2. Informative References
[1] IEEE Standards Association,
http://standards.ieee.org/develop/regauth/tut/eui64.pdf, 2012
[2] Rafiee, H., "Research Results",
http://ipv6sra.rozanak.com/Jan2013_CGA_SSAS_Comparison.pdf, 2013
[3] Brown, R., L., D. : SEC 1: Elliptic Curve Cryptography,
Certicom Research,
http://www.secg.org/download/aid-780/sec1-v2.pdf, 2009
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Authors' Addresses
Hosnieh Rafiee
Hasso-Plattner-Institute
Prof.-Dr.-Helmert-Str. 2-3
Potsdam, Germany
Phone: +49 (0)331-5509-546
Email: ietf@rozanak.com
Dr. Christoph Meinel
(Professor)
Hasso-Plattner-Institute
Prof.-Dr.-Helmert-Str. 2-3
Potsdam, Germany
Email: meinel@hpi.uni-potsdam.de
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