Internet DRAFT - draft-rafiee-6man-ssas
draft-rafiee-6man-ssas
Network Group H. Rafiee
INTERNET-DRAFT Huawei Technologies Duesseldorf GmbH
Intended status: Experimental C. Meinel
Hasso Plattner Institute
Expires: March 19, 2015 September 19, 2014
A Simple Secure Addressing Scheme for IPv6 AutoConfiguration (SSAS)
<draft-rafiee-6man-ssas-11.txt>
Abstract
Since performance and security are, both, two important criteria for
a mechanism to be widely used by different nodes with various
resources, the purpose of this document is to propose a mechanism for
local security and to prevent IP spoofing. This mechanism also
consider user's privacy.
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
material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 19, 2015.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. This document is subject to
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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. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . 4
3. Algorithms Overview . . . . . . . . . . . . . . . . . . . . . 4
3.1. Interface ID (IID) Generation . . . . . . . . . . . . . . 4
3.1.1. Signature Generation . . . . . . . . . . . . . . . . 5
3.1.2. Generation of NDP/SeND Messages . . . . . . . . . . . 6
3.1.2.1. SSAS signature data field . . . . . . . . . . . . 6
3.1.3. SSAS verification process . . . . . . . . . . . . . . 8
3.2. Resource Public key Infrastructure (RPKI) . . . . . . . . 9
4. SSAS Applications . . . . . . . . . . . . . . . . . . . . . . 9
4.1. A solution for all nodes . . . . . . . . . . . . . . . . 9
4.2. Authentication in Network layer . . . . . . . . . . . . . 9
4.3. Authentication in Application Layer . . . . . . . . . . . 10
4.4. Other Applications . . . . . . . . . . . . . . . . . . . 10
5. Security Considerations . . . . . . . . . . . . . . . . . . . 10
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
7. Privacy Consideration . . . . . . . . . . . . . . . . . . . . 11
8. Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . 11
8.1. Comparison of CGA and SSAS generation time . . . . . . . 11
9. Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.1. Network-based protection vs. Node-based protection . . . 12
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
11.1. Normative . . . . . . . . . . . . . . . . . . . . . . . . 13
11.2. Informative . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
In IPv6 networks, nodes can use two different mechanisms to configure
their IP addresses -- Neighbor Discovery Protocol (NDP) [RFC4861,
RFC4862] and Dynamic Host Configuration Protocol (DHCPv6) [RFC3315].
Unfortunately none of these mechanisms are natively secure. So, they
open the nodes with so many local security problems. There are
several attacks possible in local network [RFC3756]. One example is
IP spoofing that enable an attacker to forge the identity of a victim
node, the other example is preventing the node from configuring its
IP address.
The reasons that local security is important are as follows
[localSecurity]:
- Not all the nodes on the local link are trusted: viruses or other
malware can infect a legitimate node in the local link and turn it to
an attacker.
- Attacker might be inside the network: The networks of big
enterprises might be harmed by one of the staff that was recently
fired.
There is currently a mechanism available to secure the NDP, i.e.,
Secure Neighbor Discovery (SeND) [RFC3971]. SeND does this protection
by adding 4 options to NDP packets. Among these options,
Cryptographically Generated Addresses (CGA) [RFC3972] is a very
important option that provides the node with the proof of IP address
ownership by finding a binding between the node's public key and its
IP address. Unfortunately CGA has some problems that are listed as
follows:
- CGA sec value problem: This problem is explained in [cgaattack] and
addressed in [cgabis].
- CGA increases complexity and decreases performance: CGA uses sec
value (the value between 0 to 7) and claims to complicate the brute
force attacks. (However it is not true based on [cgaattack]) If CGA
sec value higher than 0 is in use, then this will reduce the
performance because CGA algorithm needs to repeat some steps and it
needs the high attention of the CPU and makes the CPU busy. So, CGA
sec value higher than 0, consumes more energy than other nodes that
do not use CGA. Today, the demands on malti-functioning smaller
devices are increasing but unfortunately the battery technology is
not as advanced as expected. So, the use of CGA algorithm that needs
to use higher level of energy is not ideal for these types of nodes
and the use of CGA sec value zero does not protect the node as
expected. (Please refer to appendix A for more information)
- CGA might cause privacy issue: Since the generation of CGA higher
sec values might take time. The nodes might not be willing to change
its IP address and keep this address as long as the subnet prefix is
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valid. If the node is a fixed node in the network, then it will be
vulnerable to node tracking. The node might also not change the CGA
address when it visits a new network or it might not generate any new
key pairs. In other word, it might use the same CGA parameters
(excluding prefix) as used in the old network and thus it will be
vulnerable to node tracking.
- Packet size
CGA uses RSA as a default key pair generation algorithm. This is why,
if SeND with CGA option is in use to secure NDP messages, the minimum
packet size needs to carry this public key for CGA nodes is 460
bytes. Packet size also reduces the performance and causes delays in
the network.
Since privacy and security are, both, very important issues in
everyday life, the purpose of this document is to offer an
alternative and simple addressing mechanism to generate an interface
ID (IID) which provides the node with both security and privacy while
does not sacrifice the performance, and tries to decrease the packet
size as much as possible.
2. 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.
3. Algorithms Overview
As explained earlier, one of the problems with using the current IID
generation approach is the intensive computer processing that is
needed for the IID algorithm generation. Another concern is for the
lack of security (if CGA is not in use). This is what this document
intends to address.
3.1. Interface ID (IID) Generation
To generate the IID a node will need to execute the following steps.
1. Generate key pairs (public/private keys) using one of the latest
version of ECC algorithm [RFC6090] or other fastest short key size
algorithms. . The implementations SHOULD be updated with any new
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version of ECC algorithm when ECC current version is no longer
secure. ECC is the default algorithm, but any algorithm capable of
generating a small key size in a short amount of time is viable. The
node then uses this new value for the generation of the IP address
and signature. Comparing the use of ECC to that of RSA shows that an
ECC with a 192 bit key is equivalent to a RSA with a 7680 bit key
(according to US National Security Agency) In this case the packet
size would be decreased by a factor 11 times smaller than that when
using RSA.
Note 1: The node MUST not generate the weak key. For ECC, the node
MUST not use ECC key size lower than 192 bits. If any nodes used a
weak key size, then the other nodes MUST discard receiving the
message from that node. If in future, key size 192 bits is considered
as a weak key size, the default key size value MUST be changed to the
next strong key size.
2. Execute a hash function on the public key. The default hash
function is SHA256. If in future, this hash function is no longer
secure, the node MUST use the next strong hash function.
3. Take the first 64bits of the digest and call it IID. In case
collision count is higher than 1, then depends on the number, takes
second 64 bits or third 64 bits of this hash value.
It is not RECOMMENDED to use this algorithm in case IID is less than
64 bits [variableprefix]. A node MUST obtain the prefix length
information form router advertisement messages.
4. Concatenate the IID with the local subnet prefix to set the link
local IP address.
5. Concatenate the IID with the router subnet prefix (Global subnet
prefix), obtained from the Router Advertisement (RA) message, and set
it as a tentative public IP address. This IP address will become
permanent after Duplicate Address Detection (DAD) processing. (For
more information about DAD refer to section 3.1.2.)
Note 1: In this document bits u and g does not have any particular
meaning and is used as a part of public key. This assumption is by
the clarification of using these bits in [RFC7136].
3.1.1. Signature Generation
SSAS is not dependent to SeND but it can be used as a new option of
SeND. When SSAS is used as an option of SeND, SSAS signature can be
placed as a RSA signature in SeND. If SSAS is used alone, this
section MUST be included in SSAS data structure. This proves that
SSAS is compatible to use with SeND.
The SSAS signature is added to NDP messages in order to protect them
from IP spoofing and spoofing types of attack. SSAS will provide
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proof of IP address ownership. To generate the SSAS signature, the
node needs to execute the following steps:
1. Concatenate the timestamp with the MAC address, collision count,
algorithm type and the global (public) IP address. (see figure 1)
+---------+-----------+---------------+--------------+
|timestamp|Mac address|Collision Count|Algorithm type|
| 8 bytes | 6 bytes | 3 bits | 1 byte |
+---------------------+---------------+--------------+
|Global IP address | Other Options |
| 16 bytes | variable |
+---------------------+---------------+
Figure 1 SSAS Signature format
2. Sign the resulting value from step 1, using the ECC private key
(or any other short key size algorithm), and call the resulting
output the SSAS signature.
If NDP messages contain other data that must be protected, such as
important routing information, then 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, MAC address,
Collision count and Global IP address (Router subnet prefix plus
IID).
3.1.2. Generation of NDP/SeND Messages
After a node generates its IP address, it should then process
Duplicate Address Detection in order to avoid address collisions in
the network. In order to do this the node needs to generate a
Neighbor Solicitation (NS) message. 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 the
following items: type, length, reserved, Other Len, algorithm type,
collision count, subnet prefix, other option and padding.
3.1.2.1. SSAS signature data field
+------+-------+------------+---------+
| Type |Length | Reserved |Other len|
|1 byte|1 byte | 2 bytes | 1 byte |
+----------+---------+------+---------+
| Algorithm|Collision|Subnet| Other |
| type | count |prefix|Options |
| 1 byte | 3 bits |8bytes| |
+-------------------------------------+
|Hash | Response| |
|Function | No. | SSAS Signature |
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| 1 byte | 2 byte | |
+-------------------------------------+
| padding |
+-------------------------------------+
Figure 2 NDP Message Format with SSAS Signature Data Field
- Type: This option is set to 15. This is the sequential number used
in SeND to indicate a SSAS data field.
- Length: The length of the Signature Data field, including the Type,
Length, Reserved, Algorithm type, Signature and padding, must 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 should be ignored by the
receiver.
- Other Len: The length of other options in multiples of eight. The
length of this field is 1 byte.
- Algorithm type: The algorithm used to generate key pairs and sign
the message. The length of this field is 1 byte. For ECC, this value
is 0. Future algorithms will start at one and increase from there.
- Collision count: When a collision occurs during the DAD, the node
will increment this value and store it in a file to be included in
the sent packets for as long as the current IP address is valid. This
value indicates to the node where it needs to start its check from,
i.e., the first or second or third 64 bytes from the start of the
hash value (digest) array of the public key.
- Subnet Prefix: This is the router subnet prefix.
- Hash Function: A hash function used to generate IID. The length of
this field is 1 byte. For SHA256, this value is 0. Future algorithms
will start at one and increase from there.
- Response No: This is similar to nonce but by the use of different
mechanism. This value is not random and it is a copy of timestamp. In
sender?s message, this value MUST be set to zero and in response
message (sent from a receiver node), this value MUST be set to the
timestamp of the sender?s message. The length of this field is 2
bytes. The sender node should cache this value in order to compare it
with all responses sent by other nodes. This informs the sender node
that the message is the response to his message and protects the node
against replay attack.
- Other Options. This variable-length field contains important data
that needs to be protected in the packet. The padding is used to
insure that the field is a multiple of eight in length.
- Padding. A variable-length field containing padding to insure that
the entire signature field is a multiple of eight in length. It thus
contains the number of blanks needed to make the entire signature
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field end on a multiple of eight.
All NDP messages (except RS 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 collision
count by one and this value is used as explained in the "Collision
count" item above. It will start from that section of the public key
for the generation of a new IP address. The node repeats this 3 times
and after 3 times generates a new public/private keys. Since the
likelihood of two nodes having the same value is 1/(2^63). This is
really a small value while we also considered the order of magnitude
relative to roughly 2 power 64 against sloppy implementations.
3.1.3. SSAS verification process
A node's verification process should start when it receives NDP
messages. Following are the steps used in the verification process:
1. Obtain Response No from the sender?s packet. Compare this value
with its own timestamp that used in its previous message. If it is
the same go to the next step, otherwise discard the message. (If SSAS
is a part of SeND, this step should be skipped.)
2. Obtain prefix information from its own cache or from a router
advertisement to make sure about the prefix sizes and number of bits
used for IID.
3. Obtain the timestamp from the NDP message and call this value t1.
4. Obtain the timestamp from the node's system, convert it to UTC,
and call this value t2.
5. If (t2- x) < = t1 < = (t2 + x) go to step 6. Otherwise, the
message SHOULD be discarded without further processing. The value of
x is dependent on network delays and network policy. The default
value would be the value of Round Trip Time (RTT). The
implementations SHOULD allow to set different values.
6. Obtain the public key from its own neighboring cache. If no
matches are found in the node cache and if there is a centralized
RPKI model available in the local network, then the node MIGHT obtain
this public key from that node. Otherwise go to the next step.
7. 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. (This step should be skipped when the node uses
the RPKI to obtain the other nodes' public key.)
8. Obtain the hash algorithm from the packet. By default it is
SHA256.
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9. Execute hash function on the public key. Takes 64bits, depends on
collision count, from the hash function. Compare this value with the
node's IID source IP. If it is the same, go to the next step.
Otherwise, discard the message without further processing.
10. Concatenate the timestamp with the MAC address, algorithm type,
collision count, sender's Global IP address (subnet prefix and IID),
and other options (if any) and call this entity the plain message.
11. Obtain the SSAS signature from the SSAS signature data field.
Obtain the Algorithm type from the message.
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.
After a successful verification, the node SHOULD store the public key
and MAC address of the sender node in its neighboring cache. By
default, the cache is valid for two days but the implementation
SHOULD consider a way to let the end users change this default value.
3.2. Resource Public key Infrastructure (RPKI)
To Authorize the Routers in the network and increase the security of
the nodes in this network, it is recommended to use an RPKI explained
in RFC 6494 and 6495. It is explained in more detail in
[SSASAnalysis] and local security deployment [localSecurity].
4. SSAS Applications
4.1. A solution for all nodes
SSAS is capable to be used in standard nodes (standard computers) and
nodes where limited computational resources are available. One
example is the use of SSAS in sensor networks. Sensor networks are a
prime example of nodes with limited resources (such as battery, CPU,
and etc); see RFC 4919 [RFC4919] for use in IPv6 networks. Because
currently, as explained in section 4. RFC 6775, the generation of the
IID is based on EUI-64 which makes these nodes vulnerable to privacy
and security attacks. One of these types of attack can occur during
the Duplicate Address Detection (DAD) process.
4.2. Authentication in Network layer
Another example for the use of SSAS would be in mobile networks
during the generation of IP addresses, as explained in section 4.4
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RFC 6275 [RFC6275]. The current problem with the addressing mechanism
in a mobile node is that no privacy is observed when a node moves to
another network while usually keeping its Home Address. If there were
a fast and secure mechanism available, then it would be possible to
set this Home Address and change it and re-register it to the Home
network. Another possible use for SSAS in mobile nodes could be as a
security mechanism during the configuration of Care of Address (CoA);
see section 3. RFC 5213 [RFC5213]. In that RFC, home proxy plays the
role of a home agent for mobile nodes and mobile nodes set their CoA
by the use of either stateful or stateless autoconfiguration.
Currently they MUST use IPsec in order to secure this process.
Section 4 of that RFC discusses the possibility of using another
algorithm in order to secure mobile nodes.
4.3. Authentication in Application Layer
SSAS can be used as a means of authentication for the nodes in
application layer. It is really important that the nodes know who
they are talking to. This is because a user uses an application to
connect to another node on the internet. This application either uses
a domain name of the destination node (that later translates to the
IP addresses) or directly uses the IP address of this node. This is
where the attacker can play a role and spoof this IP address and play
a MITM attack or other types of attacks. If the node uses this
approach, the attacker does not have a possibility to spoof the IP
address of the communicating node. So, this approach can mitigate IP
spoofing during the authentication of two nodes in application layer.
4.4. Other Applications
With the wide usage of IP addresses in different types of devices and
by the use of autoconfiguration mechanisms to configure these IP
addresses, the need for the use of a security algorithm is increased.
One type of application would be for use in vehicular networks or in
the car-to-car networks. There is currently some work in progress
that makes use of Neighbor Discovery. SSAS could also be a solution
for enabling fast protection against ND attacks.
5. Security Considerations
There are two security considerations:
Since SSAS cannot prevent the layer 2 attacks but can mitigate it
after the first verification, therefore one would need to use a
monitoring device to prevent MAC spoofing. The other possibility is
to have a dynamic MAC address. This means the SSAS node can use the
48 rightmost bits of the its public key as a MAC address. In this
case there is a binding between the IP address, MAC address and
public key. Since the verification process would have failed, it
cannot be spoofed. However, this approach might be problematic from
an operational view and might need to have some consideration before
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being used.
Another security consideration is how to attack SSAS. One might ask
oneself that what are the odds of an attacker being able to generate
a public key having two four sequential bytes (from two different
halves of public key) that are the same as 64 bits of that in
Interface ID? If he could, he could then generate the signature using
his own private key and thus break SSAS. Mathematically it has been
shown that the likelihood of matching 64 bits in the public key
against 64bits in the IID is 1/(2^64). in [SSASAnalysis] the analysis
of SSAS is explained and compared to CGA. Since the nodes in the
network need to keep the public key and the MAC address of other
nodes in the cache, the attacker only has a few seconds to perform
this attack and then the attacker needs to perform this attack
against the whole public key. For CGA, this value is less. in
[cgaattack], the attack in CGA was explained. So, in general, SSAS is
faster and in a good security level. In other word, SSAS tried to
address the security and performance problem exists in CGA and offer
a fastest algorithm.
6. IANA Considerations
There is no IANA consideration
7. Privacy Consideration
When an attacker is inside a local link, he is enable to identify a
node. although, this target node changes its IP address. The reason
is because the target node does not change its MAC address. However,
if the public key needs to be used for verification in other
mechanisms and not in local link, then it is RECOMMENDED that the
public/private keys to be valid for a short period of time. The
default value would be a week. The implementations need to consider
the automatic key generation to avoid administrative requirements for
this process.
8. Appendix A
8.1. Comparison of CGA and SSAS generation time
The following information was retrieved from [cgatime]. It shows the
time required to generate CGA in different sec value. This is why, in
practice, only sec value 0 and 1 can be used.
sec value 1 => ~ 1 second
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sec value 2 => ~ 3 hours
sec value 3 => ~ 24 years
sec value 4 => ~ 1.16*10^6 years
sec value 5 => ~ 1*10^11 years
sec value 6 => ~ 6.8*10^15 years
The above information is based on the fact that one uses RSA key
sizes less than 1280 bits. If one needs to use the higher security,
then it needs more time for the generation of CGA value. Using RSA
higher key sizes also increases the packet size needs to carry the
public key. Here is our evaluation of ECC and RSA key generation time
in a standard computer with 2.6 GHz CPU.
SSAS generation time is about the time needed to generate key pairs.
Since, by default, SSAS uses ECC 192 bits, the following values
compares ECC with RSA. RSA is the algorithm uses in CGA. As explained
earlier, the security of ECC 192 bits is equivalent to the security
of RSA 7680 bits.
ECC 192 bits: Average key generation time = 195011 microseconds
RSA 1280 bits: Average key generation time = 681039 microseconds
RSA 7680 bits: Average key generation time = 163473350 microseconds
9. Appendix B
9.1. Network-based protection vs. Node-based protection
Node-based protection is the ability of the node to protect against
some types of attacks such as IP spoofing, MITM attack. On the other
hand, network-based protection is the use of some devices in the
network edges to protect the nodes inside this network against router
advertisement spoofing attacks or other types of attack. Both of
these protection is required and both can complement each other. This
is because the attacker might be inside the network and play a role
of MITM, spoof the other nodes' IP address, prevent other nodes from
configuring their IP address and cause many delays and problems in
the local network (Not all the nodes in the network is ever trustee).
One important consideration about node-based protection is that, it
should support any node and apply to any nodes (Including nodes with
limited energy resources or limited memory resources). This is why
there is a need for a good mechanism to provide this protection with
less cost. The proposed mechanism in this document, i.e., SSAS can
provide the node with node-based protection. With only node-based
protection, the malicious node inside this network can claim to be a
router and the node does not have any means to authorize him. This is
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why, the network-based protection is also the complement solution to
a node-based protection. There are some approaches to provide the
node with network-based protection. One such approach might be
RA-gaurd [RAgaurd]] which limits subnet prefixes. Unfortunately with
this approach, still the node inside this network can maliciously
claim to be a router and play the MITM attack inside the network by
sending unicast router advertisement messages. So, the attack is
still possible. The other approach is the use of RPKI as explained in
RFC 6494 and RFC 6495. Unfortunately these RFCs only explain the
possibility of using them but not the detail of implementation. The
detail implementation is explained in [SSASAnalysis]. The local RPKI
node also can play a role of monitoring device in the network.
10. Acknowledgements
The Authors would like to acknowledge Erik Nordmard and Joel M.
Halpern for their supports and assistance to improve this
document.The authors also would like to acknowledge Michael
Richardson, Dan Wing, Tim Chown, Christian Huitema, Joel M. Halpern
for their comments to improve this document
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.
[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.
[RFC3756] Nikander, P., Kempf, J., Nordmark, E., "IPv6
Neighbor Discovery (ND) Trust Models and Threats", RFC
3972, May 2004.
[RFC4919] Kushalnagar, N., Montenegro, G., Schumacher, C.,"
IPv6 over Low-Power Wireless Personal Area Networks
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INTERNET DRAFT SSAS for Autoconfiguration September 19, 2014
(6LoWPANs): Overview, Assumptions, Problem Statement, and
Goals", RFC 4919, August 2007.
[RFC6775] Shelby, Z., Chakrabarti, S., Nordmark, E.,
Bormann, C. , " Neighbor Discovery Optimization for IPv6
over Low-Power Wireless Personal Area Networks (6LoWPANs)",
RFC 6775, November 2012.
[RFC6275] Perkins, C., Johnson, D., Arkko, J., "Mobility
Support in IPv6", RFC 6275, July 2011.
[RFC6543] Gundavell, S., "Reserved IPv6 Interface
Identifier for Proxy Mobile IPv6", RFC 6543, May 2012.
[RFC6090] McGrew, D., Igoe, K., Salter, M., "Fundamental
Elliptic Curve Cryptography Algorithms", RFC 6090, February
2012.
[RFC3756] Nikander, F., Kempf, J., Nordmark, E., "IPv6
Neighbor Discovery (ND) Trust Models and Threats", RFC
3756, May 2004.
[RFC7136] Carpenter, B., Jiang, S.,"Significance of IPv6
Interface Identifiers", RFC 7136, 2013
11.2. Informative References
[SSASAnalysis] Rafiee, H., Meinel, C., "'SSAS: a
Simple Secure Addressing Scheme for IPv6
AutoConfiguration". In Proceedings of the 11th IEEE
International conference on Privacy, Security and
Trust (PST), IEEE Catalog number: CFP1304F-ART, ISBN:
978-1-4673-5839-2.
[cgaattack] Rafiee,H., Meinel, C., "Possible Attack on
Cryptographically Generated Addresses (CGA)"
,http://tools.ietf.org/html/draft-rafiee-6man-cga-attack,
2014
[RAgaurd] Gont, F., "Implementation Advice for IPv6 Router
Advertisement Guard (RA-Guard)",
http://tools.ietf.org/html/draft-ietf-v6ops-ra-guard-implementation,
2012
[localSecurity] Rafiee,H., Meinel, C.,
"Recommendations for Local Security Deployments"
,http://tools.ietf.org/html/draft-rafiee-6man-local-security,
2013
[cgatime] Bos, J., Oezen, O., Hubaux, J., "Analysis and
Optimization of Cryptographically Generated Addresses", In
Proceedings of the 12th International conference on
Information Security (2009), ACM, pp. 17 ? 32.
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[variableprefix] Carpenter, B., Chown, T, Gont, F.,
Jiang, S., Petrescu, A., Yourtchenko, A.," Analysis
of the 64-bit Boundary in IPv6 Addressing",
http://tools.ietf.org/html/draft-ietf-6man-why64 ,
April 2014
[cgabis] Rafiee,H., Zhang, D., "CGA Security Improvement"
,http://tools.ietf.org/html/draft-rafiee-rfc3972-bis, 2014
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Authors' Addresses
Hosnieh Rafiee
HUAWEI TECHNOLOGIES Duesseldorf GmbH
Riesstrasse 25, 80992,
Munich, Germany
Phone: +49 (0)162 204 74 58
Email: hosnieh.rafiee@huawei.com
Christoph Meinel
Hasso-Plattner-Institute
Prof.-Dr.-Helmert-Str. 2-3
Potsdam, Germany
Email: meinel@hpi.uni-potsdam.de
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