[Search] [txt|pdfized|bibtex] [Tracker] [Email] [Diff1] [Diff2] [Nits]
Versions: 00 01 02                                                      
6lo                                                     B. Sarikaya, Ed.
Internet-Draft                                                Huawei USA
Intended status: Standards Track                                  F. Xia
Expires: April 13, 2015                    Huawei Technologies Co., Ltd.
                                                        October 10, 2014


   Lightweight and Secure Neighbor Discovery for Low-power and Lossy
                                Networks
                      draft-sarikaya-6lo-cga-nd-01

Abstract

   Modifications to 6lowpan Neighbor Discovery protocol are proposed in
   order to secure the neighbor discovery for low-power and lossy
   networks.  This document defines lightweight and secure version of
   the neighbor discovery for low-power and lossy networks.  The nodes
   generate a Cryptographically Generated Address, register the
   Cryptographically Generated Address with a default router and
   periodically refresh the registration.  Cryptographically generated
   address and digital signatures are calculated using elliptic curve
   cryptography, so that the cryptographic operations are suitable for
   low power devices.

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 April 13, 2015.

Copyright Notice

   Copyright (c) 2014 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



Sarikaya & Xia           Expires April 13, 2015                 [Page 1]


Internet-Draft                LSEND for LLN                 October 2014


   (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.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Problem Statement . . . . . . . . . . . . . . . . . . . . . .   3
   4.  New Options . . . . . . . . . . . . . . . . . . . . . . . . .   3
     4.1.  CGA Parameters and Digital Signature Option . . . . . . .   3
     4.2.  Digital Signature Option  . . . . . . . . . . . . . . . .   5
     4.3.  Calculation of the Digital Signature and CGA Using ECC  .   7
   5.  Protocol Interactions . . . . . . . . . . . . . . . . . . . .   7
     5.1.  Packet Sizes  . . . . . . . . . . . . . . . . . . . . . .   9
   6.  Optimizations . . . . . . . . . . . . . . . . . . . . . . . .   9
     6.1.  Multihop Operation  . . . . . . . . . . . . . . . . . . .  11
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   8.  IANA considerations . . . . . . . . . . . . . . . . . . . . .  12
   9.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     10.2.  Informative references . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   Neighbor discovery for IPv6 [RFC4861] and stateless address
   autoconfiguration [RFC4862], together referred to as neighbor
   discovery protocols (NDP), are defined for regular hosts operating
   with wired/wireless links.  These protocols are not suitable and
   require optimizations for resource constrained, low power hosts
   operating with lossy wireless links.  Neighbor discovery
   optimizations for 6lowpan networks include simple optimizations such
   as a host address registration feature using the address registration
   option which is sent in unicast Neighbor Solicitation (NS) and
   Neighbor Advertisement (NA) messages [RFC6775].

   Neighbor discovery protocols (NDP) are not secure especially when
   physical security on the link is not assured and vulnerable to
   attacks defined in [RFC3756].  Secure neighbor discovery protocol
   (SEND) is defined to secure NDP [RFC3971].  Cryptographically
   generated addresses (CGA) are used in SEND [RFC3972].  SEND mandates
   the use of the RSA signature algorithm which is computationally heavy



Sarikaya & Xia           Expires April 13, 2015                 [Page 2]


Internet-Draft                LSEND for LLN                 October 2014


   and not suitable to use for low-power and resource constrained nodes.
   The use of an RSA public key and signature leads to long message
   sizes not suitable to use in low-bit rate, short range, asymmetric
   and non-transitive links such as IEEE 802.15.4.

   In this document we extend the 6lowpan neighbor discovery protocol
   with cryptographically generated addresses.  The nodes generate CGAs
   and register them with the default router.  CGA generation is based
   on elliptic curve cryptography (ECC)and signature is calculated using
   elliptic curve digital signature algorithm (ECDSA) known to be
   lightweight, leading to much smaller packet sizes.  The resulting
   protocol is called Lightweight Secure Neighbor Discovery Protocol
   (LSEND).

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   The terminology in this document is based on the definitions in
   [RFC3971], [RFC3972] in addition to the ones specified in [RFC6775].

3.  Problem Statement

   6LowPAN neighbor discovery protocol [RFC6775] needs to be extended to
   make it secure and also for being more efficient as well as other use
   cases.  Requirements on such enhancements are stated in
   [I-D.thubert-6lo-rfc6775-update-reqs].

4.  New Options

4.1.  CGA Parameters and Digital Signature Option

   This option contains both CGA parameters and the digital signature.

   A summary of the CGA Parameters and Digital Signature Option format
   is shown below.













Sarikaya & Xia           Expires April 13, 2015                 [Page 3]


Internet-Draft                LSEND for LLN                 October 2014


       0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Type      |    Length     |   Pad  Length |  Sig. Length  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                                                               .
       .                        CGA Parameters                         .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                                                               .
       .                       Digital Signature                       .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                                                               .
       .                           Padding                             .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Type

      TBA1 for CGA Parameters and Digital Signature

   Length

      The length of the option (including the Type, Length, Pad Length,
      Signature Length, CGA Parameters, Digital Signature and Padding
      fields) in units of 8 octets.

   Pad Length

      The length of the Padding field.

   Sig Length

      The length of the Digital Signature field.

   CGA Parameters

      The CGA Parameters field is variable-length containing the CGA
      Parameters data structure described in Section 4 of [RFC3972].




Sarikaya & Xia           Expires April 13, 2015                 [Page 4]


Internet-Draft                LSEND for LLN                 October 2014


   Digital Signature

      The Digital Signature field is a variable length field containing
      a Elliptic Curve Digital Signature Algorithm (ECDSA) signature
      (with SHA-256 and P-256 curve of [FIPS-186-3]).  Digital signature
      is constructed as explained in Section 4.3.

   Padding

      The Padding field contains a variable-length field making the CGA
      Parameters and Digital Signature Option length a multiple of 8.

4.2.  Digital Signature Option

   This option contains the digital signature.

   A summary of the Digital Signature Option format is shown below.
   Note that this option has the same format as RSA Signature Option
   defined in [RFC3971].  The differences are that Digital Signature
   field carries an ECDSA signature not an RSA signature, and in
   calculating Key Hash field SHA-2 is used instead of SHA-1.

   In the sequence of octets to be signed using the sender's private key
   includes 128-bit CGA Message Type tag.  In LSEND, CGA Message Type
   tag of 0xE8C47FB7FD2BB885DAB2D31A0F2808B4 MUST be used.


























Sarikaya & Xia           Expires April 13, 2015                 [Page 5]


Internet-Draft                LSEND for LLN                 October 2014


       0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Type      |    Length     |           Reserved            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       |                          Key Hash                             |
       |                                                               |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                                                               .
       .                       Digital Signature                       .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                                                               .
       .                           Padding                             .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Type

      TBA2 for Digital Signature

   Length

      The length of the option (including the Type, Length, Reserved,
      Key Hash, Digital Signature and Padding fields) in units of 8
      octets.

   Key Hash

      The Key Hash field is a 128-bit field containing the most
      significant (leftmost) 128 bits of a SHA-2 hash of the public key
      used for constructing the signature.  This is the same as in
      [RFC3971] except for SHA-1 which has been replaced by SHA-2.

   Digital Signature

      Same as in Section 4.1.

   Padding





Sarikaya & Xia           Expires April 13, 2015                 [Page 6]


Internet-Draft                LSEND for LLN                 October 2014


      The Padding field contains a variable-length field containing as
      many bytes long as remain after the end of the signature.

4.3.  Calculation of the Digital Signature and CGA Using ECC

   Due to the use of Elliptic Curve Cryptography, the following
   modifications are needed to [RFC3971] and [RFC3972].

   The digital signature is constructed by using the sender's private
   key over the same sequence of octets specified in Section 5.2 of
   [RFC3971] up to all neighbor discovery protocol options preceding the
   Digital Signature option containing the ECC-based signature.  The
   signature value is computed using the ECDSA signature algorithm as
   defined in [SEC1] and hash function SHA-256.

   Public Key is the most important parameter in CGA Parameters defined
   in Section 4.1.  Public Key MUST be DER-encoded ASN.1 structure of
   the type SubjectPublicKeyInfo formatted as ECC Public Key.  The
   AlgorithmIdentifier, contained in ASN.1 structure of type
   SubjectPublicKeyInfo, MUST be the (unrestricted) id- ecPublicKey
   algorithm identifier, which is OID 1.2.840.10045.2.1, and the
   subjectPublicKey MUST be formatted as an ECC Public Key, specified in
   Section 2.2 of [RFC5480].

   Note that the ECC key lengths are determined by the namedCurves
   parameter stored in ECParameters field of the AlgorithmIdentifier.
   The named curve to use is secp256r1 corresponding to P-256 which is
   OID 1.2.840.10045.3.1.7 [SEC2].

   ECC Public Key could be in uncompressed form or in compressed form
   where the first octet of the OCTET STRING is 0x04 and 0x02 or 0x03,
   respectively.  Point compression using secp256r1 reduces the key size
   by 32 octets.  In LSEND, point compression MUST be supported.

5.  Protocol Interactions

   Lightweight Secure Neighbor Discovery for Low-power and Lossy
   Networks (LSEND for LLN) modifies Neighbor Discovery Optimization for
   Low-power and Lossy Networks [RFC6775] as explained in this section.
   Protocol interactions are shown in Figure 1.

   6LoWPAN Border Routers (6LBR) send router advertisements (RA).
   6LoWPAN Nodes (6LN, or simply "nodes") receive these RAs and generate
   their own cryptographically generated addresses using elliptic curve
   cryptography as explained in Section 4.3.  The node sends a neighbor
   solicitation (NS) message with the address registration option (ARO)
   to 6LBR.  Such a NS is called an address registration NS.




Sarikaya & Xia           Expires April 13, 2015                 [Page 7]


Internet-Draft                LSEND for LLN                 October 2014


   An LSEND for LLN node MUST send an address registration NS message
   after adding CGA Parameters and Digital Signature Option defined in
   Section 4.1.  Source address MUST be set to its crypotographically
   generated address.  An LSEND for LLN node MUST set the Extended
   Unique Identifier (EUI-64) field [Guide] in ARO to the rightmost 64
   bits of its crypotographically generated address.  The Subnet Prefix
   field of CGA Parameters MUST be set to the leftmost 64 bits of its
   crypotographically generated address.  The Public Key field of CGA
   Parameters MUST be set to the node's ECC Public Key.

   6LBR receives the address registration NS. 6LBR then verifies the
   source address as described in Section 5.1.2. of [RFC3971] using the
   claimed source address and CGA Parameters field in the message.
   After successfully verifying the address 6LBR next does a
   cryptographic check of the signature included in the Digital
   Signature field in the message.  If all checks succeed then 6LBR
   performs a duplicate address detection procedure on the address.  If
   that also succeeds 6LBR registers the CGA in the neighbor cache. 6LBR
   also caches the node's public key.

   6LBR sends an address registration neighbor advertisement (NA) as a
   reply to confirm the node's registration.  Status is set to 0 to
   indicate success.  This completes initial address registration.  The
   address registration needs to be refreshed after the neighbor cache
   entry times out.


     6LN                                                      6LBR
      |                                                         |
      |<-----------------------RA-------------------------------|
      |                                                         |
      |---------------NS with ARO and CGA Option--------------->|
      |                                                         |
      |<-----------------------NA with ARO----------------------|
      |                                                         |
      |---------------NS with ARO and Digital Signature Option->|
      |                                                         |
      |<-----------------------NA with ARO----------------------|
      |                                                         |
      |---------------NS with ARO and Digital Signature Option->|
      |                                                         |
      |<-----------------------NA with ARO----------------------|


                Figure 1: Lightweight SEND for LLN Protocol

   In order to refresh the neighbor cache entry, an LSEND for LLN node
   MUST send an address registration NS message after adding the Digital



Sarikaya & Xia           Expires April 13, 2015                 [Page 8]


Internet-Draft                LSEND for LLN                 October 2014


   Signature Option defined in Section 4.2.  The Key Hash field is a
   hash of the node's public key and MUST be set as described in
   Section 4.2.  The Digital Signature field MUST be set as described in
   Section 4.2.

   6LBR receives the address registration refresh NS. 6LBR uses the key
   hash field in Digital Signature Option to find the node's public key
   from the neighbor cache. 6LBR verifies the digital signature in the
   NS.  In case of successful verification, 6LBR sends back an address
   registration neighbor advertisement (NA) to the node and sets the
   status to 0 indicating successful refreshment of the CGA of the node.
   Similar refresh NS and NA exchanges happen afterwards as shown in
   Figure 1.

5.1.  Packet Sizes

   An original address registration NS message that contains a 40 byte
   header and ARO is 16 octets.  DER-encoded ECC Public Key for P-256
   curve is 88 octets long uncompressed and 88-32=56 octets with point
   compression.  Digital Signature field when using ECDSA for P-256
   curve is 72 octets long without padding bytes for a DER encoding of
   the ASN.1 type "ECDSA-sig-value" [ANSIX9.62].

   CGA Parameters and Digital Signature Option's CGA Parameters include
   16 octet modifier, 8 octet prefix obtained from the router
   advertisement message sent from 6LBR, 1 octet collision count and 56
   octet Public Key. Digital Signature is 72 octets.  The option is 160
   octets with Padding of 7 octets.  The total message size of an
   original LSEND address registration NS message is 216 octets and such
   a message can be encapsulated into three 802.15.4 frames.

   An address registration refresh NS message contains an ARO which is
   16 octets and the digital signature option containing 16 octet key
   hash and 71 octet signature and 5 octet Padding.  The message is 152
   octets long with the header.  Such a message could be encapsulated in
   two 802.15.4 frames.

   The overhead of LSEND is valid initially and in base LSEND, possibly
   after bootstrapping at the address registration neighbor solicitation
   message.  It disappears after that as we explain below in Section 6
   in case optimal LSEND is used.

6.  Optimizations

   In this section we present optimizations to the base LSEND defined
   above.  We use EUI-64 identifier instead of source address in CGA
   calculations.  We also extend LSEND operation to 6LoWPAN multihop
   network.



Sarikaya & Xia           Expires April 13, 2015                 [Page 9]


Internet-Draft                LSEND for LLN                 October 2014


   Digital signature and CGA are calculated over EUI-64 or interface id
   of the node.  It is only done initially at once not repeated with
   every message the node sends.  The calculation does not change even
   if the node has a new address since EUI-64 does not change.  This
   means that this CGA can be used to claim multiple targets.  The
   calculation is ECC based as described in Section 4.3.

   Protocol interactions are as defined in Section 5.  The address
   registration NS message contains CGA Parameters and Digital Signature
   Option defined in Section 4.1.  The node MUST set the Extended Unique
   Identifier (EUI-64) field [Guide] in ARO to the crypotographically
   generated address.  The Subnet Prefix field of CGA Parameters MUST be
   set to the 64-bit prefix in the RA message received from 6LBR.
   Source address MUST be set to the prefix concatenated with the node's
   crypotographically generated address.  The Public Key field of CGA
   Parameters MUST be set to the node's ECC Public Key.

   CGA calculated may need to be modified before it is used as EUI-64.
   The b2 bit or U/L or "u" bit MUST be set to zero for globally unique
   and b1 bit or I/G or "g" bit MUST be set to zero for unicast before
   using it in IPv6 address as the interface identifier.  In LSEND,
   senders and receivers ignore any differences in the three leftmost
   bits and in bits 6 and 7 (i.e., the "u" and "g" bits) in the
   interface identifiers [RFC3972].

   The Target Address field in NS message is set to the prefix
   concatenated with the node's crypotographically generated address.
   This address does not need duplicate address detection as EUI-64 is
   globally unique.  So a host cannot steal an address that is already
   registered unless it has the key for the EUI-64.  The same EUI-64 can
   thus be used to protect multiple addresses e.g. when the node
   receives a different prefix.  The node adds CGA Parameters (including
   Public Key) and Digital Signature Option defined in Section 4.1 into
   NS message.  The node sends the address registration option (ARO)
   which is set to the CGA calculated.

   Protocol interactions given in xref target="Dynamic-fig"/> are
   modified a bit in that Digital Signature option with the public key
   and ARO are passed to and stored by the 6LR/6LBR on the first NS and
   not sent again the in the next NS.

   The 6LR/6LBR ensures first-come/first-serve by storing the ARO and
   the cryptographical material correlated to the target being
   registered.  Then, if the node is the first to claim any address it
   likes, then it becomes owner of that address and the address is bound
   to the CGA in the 6LR/6LBR registry.  This procedure avoids the
   constrained device to compute multiple keys for multiple addresses.
   The registration process allows the node to tie all the addresses to



Sarikaya & Xia           Expires April 13, 2015                [Page 10]


Internet-Draft                LSEND for LLN                 October 2014


   the same EUI-64 and have the 6LR/6LBR enforce first come first serve
   after that.

6.1.  Multihop Operation

   In multihop 6LoWPAN, 6LBR sends RAs with prefixes downstream and it
   is the 6LR that receives and relays them to the nodes. 6LR and 6LBR
   communicate with the ICMPv6 Duplicate Address Request (DAR) and the
   Duplicate Address Confirmation (DAC) messages.  The DAR and DAC use
   the same message format as NS and NA with different ICMPv6 type
   values.

   In LSEND we extend DAR/DAC messages to carry CGA Parameters and
   Digital Signature Option defined in Section 4.1.

   In a multihop 6LoWPAN, the node exchanges the messages shown in
   Figure 1 with 6LR not with 6LBR.  6LBR must be aware of who owns an
   address (EUI-64) to defend the first user if there is an attacker on
   another 6LR.  Because of this the content that the source signs and
   the signature needs to be propagated to the 6LBR in DAR message.  For
   this purpose we need the DAR message sent by 6LR to 6LBR MUST contain
   CGA Parameters and Digital Signature Option carrying the CGA that the
   node calculates and its public key.  DAR message also contains ARO.

   It is possible that occasionally, 6LR may miss the node's CGA (that
   it received in ARO) or the crypto information (that it received in
   CGA Parameters and Digital Signature Option). 6LR should be able to
   ask for it again.  This is done by restarting the exchanges shown in
   Figure 1.  The result enables 6LR to refresh CGA and public key
   information that was lost. 6LR MUST send DAR message with CGA
   Parameters and Digital Signature Option and ARO to 6LBR.  6LBR as a
   reply forms a DAC message with the information copied from the DAR
   and the Status field is set to zero.  With this exchange, the 6LBR
   can (re)validate and store the CGA and crypto information to make
   sure that the 6LR is not a fake.

7.  Security Considerations

   The same considerations regarding the threats to the Local Link Not
   Covered (as in [RFC3971]) apply.

   The threats discussed in Section 9.2 of [RFC3971] are countered by
   the protocol described in this document as well.

   As to the attacks to the protocol itself, denial of service attacks
   that involve producing a very high number of packets are deemed
   unlikely because of the assumptions on the node capabilities in low-
   power and lossy networks.



Sarikaya & Xia           Expires April 13, 2015                [Page 11]


Internet-Draft                LSEND for LLN                 October 2014


8.  IANA considerations

   This document defines two new options to be used in neighbor
   discovery protocol messages and new type values for CGA Parameters
   and Digital Signature Option (TBA1) and Digital Signature Option
   (TBA2) need to be assigned by IANA.

   This document defines 0xE8C47FB7FD2BB885DAB2D31A0F2808B4 for LSEND
   CGA Message Type Tag.

9.  Acknowledgements

   Greg Zaverucha from RIM made contributions to this document.
   Comments from Pascal Thubert are appreciated.

10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC3756]  Nikander, P., Kempf, J., and E. Nordmark, "IPv6 Neighbor
              Discovery (ND) Trust Models and Threats", RFC 3756, May
              2004.

   [RFC3971]  Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure
              Neighbor Discovery (SEND)", RFC 3971, March 2005.

   [RFC3972]  Aura, T., "Cryptographically Generated Addresses (CGA)",
              RFC 3972, March 2005.

   [RFC4861]  Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
              "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
              September 2007.

   [RFC4862]  Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
              Address Autoconfiguration", RFC 4862, September 2007.

   [RFC5480]  Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
              "Elliptic Curve Cryptography Subject Public Key
              Information", RFC 5480, March 2009.

   [RFC6775]  Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann,
              "Neighbor Discovery Optimization for IPv6 over Low-Power
              Wireless Personal Area Networks (6LoWPANs)", RFC 6775,
              November 2012.




Sarikaya & Xia           Expires April 13, 2015                [Page 12]


Internet-Draft                LSEND for LLN                 October 2014


   [SEC1]     "Standards for Efficient Crtptography Group.  SEC 1:
              Elliptic Curve Cryptography Version 2.0", May 2009.

   [Guide]    "Guidelines for 64-bit global Identifier (EUI-64TM)",
              November 2012,
              <http://standards.ieee.org/develop/regauth/tut/eui64.pdf>.

   [ANSIX9.62]
              "American National Standards Institute (ANSI), ANS
              X9.62-2005: The Elliptic Curve Digital Signature Algorithm
              (ECDSA)", November 2005.

10.2.  Informative references

   [SEC2]     "Standards for Efficient Crtptography Group.  SEC 2:
              Recommended Elliptic Curve Domain Parameters Version 2.0",
              January 2010.

   [FIPS-186-3]
              "National Institute of Standards and Technology, "Digital
              Signature Standard"", June 2009.

   [NIST-ST]  "National Institute of Standards and Technology, "NIST
              Comments on Cryptanalytic Attackts on SHA-1"", January
              2009,
              <http://csrc.nist.gov/groups/ST/hash/statement.html>.

   [I-D.rafiee-6man-ssas]
              Rafiee, H. and C. Meinel, "A Simple Secure Addressing
              Scheme for IPv6 AutoConfiguration (SSAS)", draft-rafiee-
              6man-ssas-11 (work in progress), September 2014.

   [I-D.thubert-6lo-rfc6775-update-reqs]
              Thubert, P., "Requirements for an update to 6LoWPAN ND",
              draft-thubert-6lo-rfc6775-update-reqs-04 (work in
              progress), August 2014.

Authors' Addresses

   Behcet Sarikaya (editor)
   Huawei USA
   5340 Legacy Dr. Building 3
   Plano, TX  75024

   Email: sarikaya@ieee.org






Sarikaya & Xia           Expires April 13, 2015                [Page 13]


Internet-Draft                LSEND for LLN                 October 2014


   Frank Xia
   Huawei Technologies Co., Ltd.
   101 Software Avenue, Yuhua District
   Nanjing,  Jiangsu  210012, China

   Phone: ++86-25-56625443
   Email: xiayangsong@huawei.com












































Sarikaya & Xia           Expires April 13, 2015                [Page 14]