OSPF Working Group                                             M. Bhatia
Internet-Draft                                            Ionos Networks
Intended status: Standards Track                              S. Hartman
Expires: April 9, 2015                                 Painless Security
                                                                D. Zhang
                                           Huawei Technologies co., LTD.
                                                               A. Lindem
                                                                   Cisco
                                                         October 6, 2014


     Security Extension for OSPFv2 when using Manual Key Management
          draft-ietf-ospf-security-extension-manual-keying-09

Abstract

   The current OSPFv2 cryptographic authentication mechanism as defined
   in RFC 2328 and RFC 5709 is vulnerable to both inter-session and
   intra-session replay attacks when using manual keying.  Additionally,
   the existing cryptographic authentication mechanism does not cover
   the IP header.  This omission can be exploited to carry out various
   types of attacks.

   This draft proposes changes to the authentication sequence number
   mechanism that will protect OSPFv2 from both inter-session and intra-
   session replay attacks when using manual keys for securing OSPFv2
   protocol packets.  Additionally, we also describe some changes in the
   cryptographic hash computation that will eliminate attacks resulting
   from OSPFv2 not protecting the IP header.

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 9, 2015.

Copyright Notice



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   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
   (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 . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Requirements Section . . . . . . . . . . . . . . . . . . .  3
     1.2.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . .  4
   2.  Replay Protection using Extended Sequence Numbers  . . . . . .  4
   3.  OSPF Packet Extensions . . . . . . . . . . . . . . . . . . . .  5
   4.  OSPF Packet Key Selection  . . . . . . . . . . . . . . . . . .  6
     4.1.  Key Selection for Unicast OSPF Packet Transmission . . . .  7
     4.2.  Key Selection for Multicast OSPF Packet Transmission . . .  8
     4.3.  Key Selection for OSPF Packet Reception  . . . . . . . . .  8
   5.  Securing the IP header . . . . . . . . . . . . . . . . . . . .  9
   6.  Mitigating Cross-Protocol Attacks  . . . . . . . . . . . . . .  9
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 10
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 11
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 11
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 12
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13


















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1.  Introduction

   The OSPFv2 cryptographic authentication mechanism as described in
   [RFC2328] uses per-packet sequence numbers to provide protection
   against replay attacks.  The sequence numbers increase monotonically
   so that attempts to replay stale packets can be thwarted.  The
   sequence number values are maintained as a part of neighbor adjacency
   state.  Therefore, if an adjacency is taken down, the associated
   sequence numbers get reinitialized and neighbor adjacency formation
   starts over again.  Additionally, the cryptographic authentication
   mechanism does not specify how to deal with the rollover of a
   sequence number when its value wraps.  These omissions can be
   exploited by attackers to implement various replay attacks
   ([RFC6039]).  In order to address these issues, we propose extensions
   to the authentication sequence number mechanism.

   The cryptographic authentication as described in [RFC2328] and later
   updated in [RFC5709] does not include the IP header.  This omission
   can be exploited to launch several attacks as the source address in
   the IP header is not protected.  The OSPF specification, for
   broadcast and NBMA (Non-Broadcast Multi-Access Networks), requires
   implementations to use the source address in the IP header to
   determine the neighbor from which the packet was received.  Changing
   the IP source address of a packet to a conflicting IP address can be
   exploited to produce a number of denial of service attacks [RFC6039].
   If the packet is interpreted as coming from a different neighbor, the
   received sequence number state for that neighbor may be incorrectly
   updated.  This attack may disrupt communication with a legitimate
   neighbor.  Hello packets may be reflected to cause a neighbor to
   appear to have one-way communication.  Additionally, Database
   Description packets may be reflected in cases where the per-packet
   sequence numbers are sufficiently divergent in order to disrupt an
   adjacency [RFC6863].  This is referred to as the IP layer issue in
   [RFC6862].

   [RFC2328] states that implementations MUST offer keyed MD5
   authentication.  It is likely that this will be deprecated in favor
   of the stronger algorithms described in [RFC5709] and required in
   [RFC6094].

   This draft proposes a few simple changes to the cryptographic
   authentication mechanism, as currently described in [RFC5709], to
   prevent such IP layer attacks.

1.1.  Requirements Section

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this



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   document are to be interpreted as described in RFC2119 [RFC2119].

   When used in lowercase, these words convey their typical use in
   common language, and are not to be interpreted as described in
   RFC2119 [RFC2119].

1.2.  Acknowledgments

   Thanks to Ran Atkinson for help in the analysis of RFC 6506 errata
   leading to clarifications in this document.  Thanks to Gabi Nakibly
   for pointing out the possible attack on p2p links.


2.  Replay Protection using Extended Sequence Numbers

   In order to provide replay protection against both inter-session and
   intra-session replay attacks, the OSPFv2 sequence number is expanded
   to 64-bits with the least significant 32-bit value containing a
   strictly increasing sequence number and the most significant 32-bit
   value containing the boot count.  OSPFv2 implementations are required
   to retain the boot count in non-volatile storage for the deployment
   life the OSPF router.  The requirement to preserve the boot count is
   also placed on SNMP agents by the SNMPv3 security architecture (refer
   to snmpEngineBoots in [RFC4222]).

   Since there is no room in the OSPFv2 packet for a 64-bit sequence
   number, it will occupy the 8 octets following the OSPFv2 packet and
   MUST be included when calculating the OSPFv2 packet digest.  These
   additional 8 bytes are not included in the OSPFv2 packet header
   length but are included in the OSPFv2 header Authentication Data
   length and the IPv4 packet header length.

   The lower order 32-bit sequence number MUST be incremented for every
   OSPF packet sent by the OSPF router.  Upon reception, the sequence
   number MUST be greater than the sequence number in the last OSPF
   packet of that type accepted from the sending OSPF neighbor.
   Otherwise, the OSPF packet is considered a replayed packet and
   dropped.  OSPF packets of different types may arrive out of order if
   they are prioritized as recommended in [RFC3414].

   OSPF routers implementing this specification MUST use available
   mechanisms to preserve the sequence number's strictly increasing
   property for the deployed life of the OSPFv3 router (including cold
   restarts).  This is achieved by maintaining a boot count in non-
   volatile storage and incrementing it each time the OSPF router loses
   its prior sequence number state.  The SNMPv3 snmpEngineBoots variable
   [RFC4222] MAY be used for this purpose.  However, maintaining a
   separate boot count solely for OSPF sequence numbers has the



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   advantage of decoupling SNMP reinitialization and OSPF
   reinitialization.  Also, in the rare event that the lower order 32-
   bit sequence number wraps, the boot count can be incremented to
   preserve the strictly increasing property of the aggregate sequence
   number.  Hence, a separate OSPF boot count is RECOMMENDED.


3.  OSPF Packet Extensions

   The OSPF packet header includes an authentication type field, and 64-
   bits of data for use by the appropriate authentication scheme
   (determined by the type field).  Authentication types 0, 1 and 2 are
   defined [RFC2328].  This section of this defines Authentication type
   TBD (3 is recommended).

   When using this authentication scheme, the 64-bit Authentication
   field in the OSPF packet header as defined in section D.3 of
   [RFC2328] is changed as shown below.  The sequence number is removed
   and the Key ID is extended to 32 bits and moved to the former
   position of the sequence number.

   Additionally, the 64-bit sequence number is moved to the first 64-
   bits following the OSPFv2 packet and is protected by the
   authentication digest.  These additional 64 bits or 8 octets are
   included in the IP header length but not the OSPF header packet
   length.

























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        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  Version #  |     Type        |       Packet length           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          Router ID                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Area ID                             |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           Checksum            |             AuType            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                               0               | Auth Data Len |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Key ID                                |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       |                   OSPF Protocol Packet                        |
       ~                                                               ~
       |                                                               |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Sequence Number (Boot Count)                              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Sequence Number (Strictly Increasing Packet Counter)      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       ~                     Authentication Data                       ~
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


       Figure 1 -  Extended Sequence Number Packet Extensions


4.  OSPF Packet Key Selection

   This section describes how the proposed security solution selects
   long-lived keys from key tables.  [I-D.ietf-karp-crypto-key-table].
   Generally, a key used for OSPFv2 packet authentication should satisfy
   the following requirements:

   o  For packet transmission, the key validity interval as defined by
      SendLifetimeStart and SendLifetimeEnd must include the current
      time.

   o  For packet reception, the key validity interval as defined by
      AcceptLifetimeStart and AcceptLifetimeEnd must include the current
      time.



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   o  The key must be valid for the desired security algorithm.

   In the remainder of this section, additional requirements for keys
   are enumerated for different scenarios.

4.1.  Key Selection for Unicast OSPF Packet Transmission

   Assume that a router R1 tries to send a unicast OSPF packet from its
   interface I1 to the interface I2 of a remote router R2 using security
   protocol P via interface I at time T. First, consider the
   circumstances where R1 and R2 are not connected with a virtual link.
   R1 then needs to select a long long-lived symmetric key from its key
   table.  Because the key should be shared by both R1 and R2 to protect
   the communication between I1 and I2, the key should satisfy the
   following requirements:

   o  The Peers field is unused.  OSPF authentication is interface
      based.

   o  The Interfaces field includes the local IP address of the
      interface for numbered interfaces or the MIB-II [RFC1213] ifIndex
      for unnumbered interfaces.

   o  The Direction field is either "out" or "both".

   o  If multiple keys match the Interfaces field, the key with the most
      recent SendLifetimeStart time will be selected.  This will
      facilitate graceful key rollover.

   o  The Key ID field in the OSPFv2 header (refer to figure 1) will be
      set to the selected key's LocalKeyName.

   When R1 and R2 are connected to a virtual link, the Interfaces field
   must identify the virtual endpoint rather than the virtual link.
   Since there may be virtual links to the same router, the transit area
   ID must be part of the identifier.  Hence, the key should satisfy the
   following requirements:

   o  The Peers field is unused.  OSPF authentication is interface
      based.

   o  The Interfaces field includes both the virtual endpoint's OSPF
      router ID and the transit area ID for the virtual link.

   o  The Direction field is either "out" or "both".

   o  If multiple keys match the Interfaces field, the key with the most
      recent SendLifetimeStart time will be selected.  This will



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      facilitate graceful key rollover.

   o  The Key ID field in the OSPFv2 header (refer to figure 1) will be
      set to the selected key's LocalKeyName.

4.2.  Key Selection for Multicast OSPF Packet Transmission

   If a router R1 sends an OSPF packet from its interface I1 to a
   multicast address (i.e., AllSPFRouters or AllDRouters), it needs to
   select a key according to the following requirements:

   o  The Peers field is unused.  OSPF authentication is interface
      based.

   o  The Interfaces field includes the local IP address of the
      interface for numbered interfaces or the MIB-II [RFC1213] ifIndex
      for unnumbered interfaces.

   o  The Direction field is either "out" or "both".

   o  If multiple keys match the Interfaces field, the key with the most
      recent SendLifetimeStart time will be selected.  This will
      facilitate graceful key rollover.

   o  The Key ID field in the OSPFv2 header (refer to figure 1) will be
      set to the selected key's LocalKeyName.

4.3.  Key Selection for OSPF Packet Reception

   When Cryptographic Authentication is used, the ID of the
   authentication key is included in the authentication field of the
   OSPF packet header.  Using this Key ID, it is straight forward for a
   receiver to locate the corresponding key.  The simple requirements
   are:

   o  The interface on which the key was received is associated with the
      key's interface.

   o  The Key ID obtained from the OSPFv2 packet header corresponds to
      the neighbor's PeerKeyName.  Since OSPFv2 keys are symmetric, the
      LocalKeyName and PeerKeyName for OSPFv2 keys will be identical.
      Hence, the Key ID will be used to select the correct local key.

   o  The Direction field is either "in" or "both".







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5.  Securing the IP header

   This document updates the definition of the Apad constant, as it is
   defined in [RFC5709], to include the IP source address from the IP
   header of the OSPFv2 protocol packet.  The overall cryptographic
   authentication process defined in [RFC5709] remains unchanged.  To
   reduce the potential for confusion, this section minimizes the
   repetition of text from RFC 5709 [RFC5709].  The changes are:

   RFC 5709, Section 3.3, describes how the cryptographic authentication
   must be computed.  In RFC 5709, the First-Hash includes the OSPF
   packet and Authentication Trailer.  With this specification, the 64-
   bit sequence number will be included in the First-Hash along with the
   Authentication Trailer and OSPF packet.

   RFC 5709, Section 3.3 also requires the OSPFv2 packet's
   Authentication Trailer (which is the appendage described in RFC 2328,
   Section D.4.3, Page 233, items (6)(a) and (6)(d)) to be filled with
   the value Apad.  Apad is a hexadecimal constant with the value
   0x878FE1F3 repeated (L/4) times, where L is the length of the hash
   being used and is measured in octets rather than bits.

   OSPF routers sending OSPF packets must initialize Apad to the value
   of the IP source address that would be used when sending an OSPFv2
   packet, repeated L/4 times, where L is the length of the hash,
   measured in octets.  The basic idea is to incorporate the IP source
   address from the IP header in the cryptographic authentication
   computation so that any change of IP source address in a replayed
   packet can be detected.

   When an OSPF packet is received, implementations MUST initialize Apad
   as the IP source address from the IP Header of the incoming OSPFv2
   packet, repeated L/4 times, instead of the constant that's currently
   defined in [RFC5709].  Besides changing the value of Apad, this
   document does not introduce any other changes to the authentication
   mechanism described in [RFC5709].  This would prevent all attacks
   where a rogue OSPF router changes the IP source address of an OSPFv2
   packet and replays it on the same multi-access interface or another
   interface since the IP source address is now included in the
   cryptographic hash computation and modification would result in the
   OSPFv2 packet being dropped due to an authentication failure.


6.  Mitigating Cross-Protocol Attacks

   In order to prevent cross-protocol replay attacks for protocols
   sharing common keys, the two octet OSPFv2 Cryptographic Protocol ID
   is appended to the authentication key prior to use.  Refer to IANA



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   Considerations (Section 8).

   [RFC5709], Section 3.3 describes the mechanism to prepare the key
   used in the hash computation.  This document updates the sub section
   "PREPARATION OF KEY" as follows:

   The OSPFv2 Cryptographic Protocol ID is appended to the
   Authentication Key (K) yielding a Protocol-Specific Authentication
   Key (Ks).  In this application, Ko is always L octets long.  While
   [RFC2104] supports a key that is up to B octets long, this
   application uses L as the Ks length consistent with [RFC4822],
   [RFC5310], and [RFC5709].  According to [FIPS-198], Section 3, keys
   greater than L octets do not significantly increase the function
   strength.  Ks is computed as follows:

   If the Protocol-Specific Authentication Key (Ks) is L octets long,
   then Ko is equal to Ks.  If the Protocol-Specific Authentication Key
   (Ks) is more than L octets long, then Ko is set to H(Ks).  If the
   Protocol-Specific Authentication Key (Ks) is less than L octets long,
   then Ko is set to the Protocol-Specific Authentication Key (Ks) with
   zeros appended to the end of the Protocol-Specific Authentication Key
   (Ks) such that Ko is L octets long.

   Once the cryptographic key (Ko) used with the hash algorithm is
   derived the rest of the authentication mechanism described in
   [RFC5709] remains unchanged other than one detail that was
   unspecified.  When XORing Ko and Ipad of Opad, Ko MUST be padded with
   zeros to the length of Ipad or Opad.  It is expected that RFC 5709
   [RFC5709] implementations perform this padding implicitly.


7.  Security Considerations

   This document rectifies the manual key management procedure that
   currently exists within OSPFv2, as part of the Phase 1 of the KARP
   Working Group.  Therefore, only the OSPFv2 manual key management
   mechanism is considered.  Any solution that takes advantage of the
   automatic key management mechanism is beyond the scope of this
   document.

   The proposed sequence number extension offers most of the benefits of
   more complicated mechanisms without their attendant challenges.
   There are, however, a couple drawbacks to this approach.  First, it
   requires the OSPF implementation to be able to save its boot count in
   non-volatile storage.  If the non-volatile storage is ever repaired
   or upgraded such that the contents are lost or the OSPFv2 router is
   replaced, the authentication keys MUST be changed to prevent replay
   attacks.



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   Second, if a router is taken out of service completely (either
   intentionally or due to a persistent failure), the potential exists
   for reestablishment of an OSPFv2 adjacency by replaying the entire
   OSPFv2 session establishment.  However, this scenario is extremely
   unlikely, since it would imply an identical OSPFv2 adjacency
   formation packet exchange.  Without adjacency formation, the replay
   of OSPFv2 hello packets alone for an OSPFv2 router that has been
   taken out of service should not result in any serious attack as the
   only consequence is superfluous processing.  Of course, this attack
   could also be thwarted by changing the relevant manual keys.

   This document also provides a solution to prevent certain denial of
   service attacks that can be launched by changing the source address
   in the IP header of an OSPFv2 protocol packet.

   Using a single crypto sequence number can leave the router vulnerable
   to a replay attack where it uses the same source IP address on two
   different point-to-point unnumbered links.  In such environments
   where an attacker can actively tap the point-to-point links, its
   recommended that the user employes different keys on each of those
   unnumbered IP interfaces.


8.  IANA Considerations

   This document requests a new code point from the "OSPF Shortest Path
   First (OSPF) Authentication Codes" registry:

   o  3 - Cryptographic Authentication with Extended Sequence Numbers.

   This document also requests a new code point from the "Authentication
   Cryptographic Protocol ID" registry defined under "Keying and
   Authentication for Routing Protocols (KARP) Parameters":

   o  2 - OSPFv2.


9.  References

9.1.  Normative References

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

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [RFC5709]  Bhatia, M., Manral, V., Fanto, M., White, R., Barnes, M.,
              Li, T., and R. Atkinson, "OSPFv2 HMAC-SHA Cryptographic



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              Authentication", RFC 5709, October 2009.

9.2.  Informative References

   [FIPS-198]
              US National Institute of Standards & Technology, "The
              Keyed-Hash Message Authentication Code (HMAC)", FIPS PUB
              198 , March 2002.

   [I-D.ietf-karp-crypto-key-table]
              Housley, R., Polk, T., Hartman, S., and D. Zhang,
              "Database of Long-Lived Symmetric Cryptographic Keys",
              draft-ietf-karp-crypto-key-table-10 (work in progress),
              December 2013.

   [RFC1213]  McCloghrie, K. and M. Rose, "Management Information Base
              for Network Management of TCP/IP-based internets:MIB-II",
              STD 17, RFC 1213, March 1991.

   [RFC2104]  Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
              Hashing for Message Authentication", RFC 2104,
              February 1997.

   [RFC3414]  Blumenthal, U. and B. Wijnen, "User-based Security Model
              (USM) for version 3 of the Simple Network Management
              Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.

   [RFC4222]  Choudhury, G., "Prioritized Treatment of Specific OSPF
              Version 2 Packets and Congestion Avoidance", BCP 112,
              RFC 4222, October 2005.

   [RFC4822]  Atkinson, R. and M. Fanto, "RIPv2 Cryptographic
              Authentication", RFC 4822, February 2007.

   [RFC5310]  Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R.,
              and M. Fanto, "IS-IS Generic Cryptographic
              Authentication", RFC 5310, February 2009.

   [RFC6039]  Manral, V., Bhatia, M., Jaeggli, J., and R. White, "Issues
              with Existing Cryptographic Protection Methods for Routing
              Protocols", RFC 6039, October 2010.

   [RFC6094]  Bhatia, M. and V. Manral, "Summary of Cryptographic
              Authentication Algorithm Implementation Requirements for
              Routing Protocols", RFC 6094, February 2011.

   [RFC6862]  Lebovitz, G., Bhatia, M., and B. Weis, "Keying and
              Authentication for Routing Protocols (KARP) Overview,



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              Threats, and Requirements", RFC 6862, March 2013.

   [RFC6863]  Hartman, S. and D. Zhang, "Analysis of OSPF Security
              According to the Keying and Authentication for Routing
              Protocols (KARP) Design Guide", RFC 6863, March 2013.


Authors' Addresses

   Manav Bhatia
   Ionos Networks
   Bangalore,
   India

   Phone:
   Email: manav@ionosnetworks.com


   Sam Hartman
   Painless Security

   Email: hartmans@painless-security.com


   Dacheng Zhang
   Huawei Technologies co., LTD.
   Beijing,
   China

   Phone:
   Fax:
   Email: zhangdacheng@huawei.com
   URI:


   Acee Lindem
   Cisco
   USA

   Phone:
   Email: acee@cisco.com










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