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Versions: 00 01

IETF MANET                                                      C. Adjih
Internet-Draft                                                S. Boudjit
Expires: January 19, 2006                                     P. Jacquet
                                                              A. Laouiti
                                                          P. Muhlethaler
                                              INRIA Rocquencourt, France
                                                                Pr. Mase
                                           Information and Communication
                                        Network Lab., Niigata University
                                                           July 18, 2005


   Address autoconfiguration in Optimized Link State Routing Protocol
            draft-laouiti-manet-olsr-address-autoconf-01.txt

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   This Internet-Draft will expire on January 19, 2006.

Copyright Notice

   Copyright (C) The Internet Society (2005).

Abstract

   Several MANET routing protocols have been recently promoted to
   experimental RFCs.  However, autoconfiguration of MANET networks is



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   still an unsettled area.  This document proposes a protocol for
   autoconfiguration for both IPv4 or IPv6.  Its corner stone is an
   conflict-detection algorithm.  It aims at conceptual simplicity:
   essentially, each node periodically sends its addresses and an
   identifier.  Conflicts are detected as identifier mismatches.  This
   protocol might be used with any MANET protocol, although it naturally
   suits the OLSR routing protocol (on which we focus), with a light
   increase of control message overhead.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1   Changes  . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.2   Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Problem Statement  . . . . . . . . . . . . . . . . . . . . . .  5
   3.  Overview of the Method . . . . . . . . . . . . . . . . . . . .  6
     3.1   Address Assignment . . . . . . . . . . . . . . . . . . . .  6
     3.2   Duplicate Address Detection  . . . . . . . . . . . . . . .  7
     3.3   Conflict Resolution  . . . . . . . . . . . . . . . . . . .  7
     3.4   Optional: MANET connected to an external network . . . . .  7
     3.5   Optional: Routing Table Contamination Avoidance  . . . . .  7
     3.6   Optional: Passive Duplicate Detection  . . . . . . . . . .  8
   4.  Duplicate Address Detection Algorithms . . . . . . . . . . . .  9
     4.1   Overview of the Different Solutions  . . . . . . . . . . .  9
     4.2   First approach . . . . . . . . . . . . . . . . . . . . . . 10
       4.2.1   Rule 1 . . . . . . . . . . . . . . . . . . . . . . . . 10
       4.2.2   Rule 2 . . . . . . . . . . . . . . . . . . . . . . . . 10
     4.3   Second approach  . . . . . . . . . . . . . . . . . . . . . 11
       4.3.1   Rule 2B  . . . . . . . . . . . . . . . . . . . . . . . 11
     4.4   Third approach . . . . . . . . . . . . . . . . . . . . . . 11
       4.4.1   Rule 2C  . . . . . . . . . . . . . . . . . . . . . . . 11
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   A.  MAD Message Format . . . . . . . . . . . . . . . . . . . . . . 15
   B.  DAD-MPR flooding algorithm . . . . . . . . . . . . . . . . . . 16
   C.  Precisions for third approach  . . . . . . . . . . . . . . . . 18
   7.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
     7.1   Normative References . . . . . . . . . . . . . . . . . . . 19
     7.2   Informative References . . . . . . . . . . . . . . . . . . 19
       Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 20
       Intellectual Property and Copyright Statements . . . . . . . . 22










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1.  Introduction

   Mobile Ad hoc NETworks (MANETs) are infrastructure-free, highly
   dynamic wireless networks, where central administration or
   configuration by the user is very difficult.  In hardwired networks
   nodes usually rely on a centralized server and use a dynamic host
   configuration protocol, like DHCP[10], to acquire an IP address.
   Such a solution cannot be deployed in MANETs due to the
   unavailability of any centralized DHCP server.  For small scale
   MANETs, it may be possible to allocate free IP addresses manually.

   However, the procedure becomes impractical for a large-scale or open
   systems where mobile nodes are free to join and leave.  Most of the
   autoconfiguration algorithms proposed for ad hoc networks are
   independent of the routing protocols and therefore, generate a
   significant overhead.  Using the genuine optimization of the
   underlying routing protocol can significantly reduce the
   autoconfiguration overhead.

   Because traditional IP solutions to autoconfiguration cannot be used
   as is on MANET networks, a MANET-AUTOCONF effort was set with three
   initial goals, which include the two following: an "IPv6 stateless
   autoconfiguration mechanism", and a "mechanism promoting address
   uniqueness in the situation where different ad hoc networks merge".
   This document proposes a protocol that addresses these two issues.
   The third one, "stateful address autoconfiguration mechanism", might
   be addressed by derivative of the method of the draft.

   This comprehensive scheme centers on one control message and one
   mechanism, which ensure at the same time conflict avoidance in the
   2-hop neighborhood of each node, and conflict avoidance in the entire
   network.  This algorithm operates on multiple interfaces and is shown
   to work in any case of multiple conflicts, especially during network
   mergers.

1.1  Changes

   Major changes from version 00 to version 01

   o  Changes in the structure of the document, and important editorial
      changes.

   o  DAD and MPR flooding is ensured in case of multiple interfaces.

   o  The second (now third) approach does not modify the basic OLSR
      HELLO message format anymore.





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   o  Another approach has been added.


1.2  Terminology

   The keywords "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 [14].

   For the OLSR description and terminology, the reader should refer to
   the OLSR RFC [12].








































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2.  Problem Statement

   The problem solved by the proposed autoconfiguration protocol is the
   autoconfiguration in MANET networks.  The reader is referred to the
   autoconfiguration survey in [1], for the general problem statement,
   and a survey of several proposed solutions.

   Considering the connectivity scenarios listed in [3], our prime
   objective is the autoconfiguration of isolated MANETs, but extending
   it to MANETs intermittently connected, or to connected MANETs is
   intended and already proposed ([5]).

   More importantly, our main goal is promoting configured address
   uniqueness in the situation where different ad hoc networks merge.
   Precisely, the networks may be isolated, may become partitioned, and
   may merge, ... .  Under these hypothesis, the only way to ensure
   address uniqueness is that, in the critical case of a merge of two
   networks, the information about the all the addresses of the first
   network is compared to the information about all the addresses of the
   second network.  That can be done in direct or indirect ways, with
   centralized or distributed means (and anything in between).






























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3.  Overview of the Method

   With respect to the problem statement, the method is build around a
   conceptually simple means of ensuring that information about all
   addresses is checked: each node sends its lists of addresses
   periodically, and a node identifier.  Hence the approach is fully
   distributed, and introduces an unique new kind of message.  It
   deliberately favors simplicity at the expense of bandwidth
   efficiency.  At least in the case of the OLSR protocol, this is not
   an issue.

   More precisely, our proposed auto-configuration algorithm is
   structured around three building blocks:

   1.  Address assignment: an IP address is selected by the arriving
       node.

   2.  Duplicate Address Detection (Conflict Detection): each node
       checks that there is not another node with the same address.

   3.  Conflict resolution: when a node detects that another node is
       using the same address, it will select a new address.

   This method may also integrate a number of optional elements, namely:

   1.  Route contamination avoidance and gradual entry (borrowed from
       [4]).

   2.  Interface with gateways (see also [5]).

   3.  Passive duplicate detection methods.

   The following sections give an overview of each part of the protocol.

3.1  Address Assignment

   Numerous schemes can be used to select an IP address.  For instance,
   the node can perform a random selection; another technique is that
   each node may advertise a set of addresses that (it believes) are not
   used, for potential newcomers as in [2].  Another method, more
   direct, is that a neighbor node selects this IP address for the
   arriving node by control message exchanges [14].

   Because it is assumed that the MANET network may be isolated, a
   default method is to choose an address at random inside a given
   subnet with MANET_PREFIX: the pool of addresses could be for local
   use only.  For example, it could be reserved by the IANA authority
   for local MANET forwarding ( i.e, those addresses must not be



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   forwarded outside the MANET network, nor reached from outside).
   Choice may be more subtle, see Section 3.5.  Additional addresses may
   be added, see Section 3.4.

3.2  Duplicate Address Detection

   As highlighted previously, the DAD algorithm uses a single special
   control message to perform conflict detection.

   This control packet includes one identifier and all the addresses of
   the node.  This message is periodically transmitted to the entire
   network.  The identifier of each node is assumed unique (with
   sufficient probability).  If a node receives a message with a
   different identifier than its own, an address duplication is detected
   and the node selects a new address.

   This control message is called MAD, for "Multiple Address
   Declaration".  It is an extension of MID messages for OLSR and it
   also advertises all acquired addresses of the node.  Because it is
   the central part of this method, it is described in the Section 4.

3.3  Conflict Resolution

   When two nodes A1 and A2 are configured with the same IP address and
   assuming that there is no packet loss, at least one of these two
   nodes will receive the MAD message of the other node.  Thus the nodes
   where the conflict lies are bound to discover the conflict, and can
   resolve it by changing addresses.  Since a conflicting node knows via
   the reception of the MAD control messages the already assigned
   addresses, the new address must be selected at random among the
   addresses that are believed to be free.

3.4  Optional: MANET connected to an external network

   When a MANET is connected to an external network, in case of IPv6,
   the node may receive IPv6 router advertisement messages.  The intent
   of MAD messages was to advertise all the addresses of a node,
   including newly formed global addresses when such an IPv6 router
   advertisement is received (diffused by a manet multicast), see [14].
   A better and more complete protocol to achieve the same goals (and
   more) is described in [5], and it can be adapted directly to the
   method presented here.

3.5  Optional: Routing Table Contamination Avoidance

   In the case that node has just changed its address, an useful
   technique is to perform some routing table contamination avoidance
   (pioneered in [4]).  It consists into letting a node entering



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   gradually in the network, going through several states: at first it
   is only recognized by its immediate neighbors, but not advertised,
   and not used for routing.  This gives the node opportunity to detect
   (passively) an address conflict with an existing node, and change its
   address.

3.6  Optional: Passive Duplicate Detection

   When the OLSR routing protocol is used (version 1 or version 2), it
   is possible to use a derivative of passive detection techniques found
   in NOA-OLSR [4] and [2], and pioneered by PACMAN [9]: the topological
   information diffused by the OLSR routing protocol is sufficient to
   detect address conflict.  The address conflicts are essentially
   detected in two ways, as analyzed in [9]: inconsistent topological
   information (essentially, a node discovers that a control message
   incorrectly advertises that it has a link), and inconsistent message
   originators (a node discovers that it is credited for originating a
   message, which actually, it did not transmit).

   Using passive techniques, one still need to ensure that control
   messages are propagated properly.  Especially in the case of OLSR
   with multiple interfaces (but also in the cases given in the figures
   of [9]), it is necessary to ensure that MPR selection is done
   properly: we propose that MPR selection is ensured by the propagation
   of MAD messages at only a distance up to two hops from the
   originator, (4 hops when conflict is detected, as the algorithms
   proposed here do), which is enough to guarantee sufficient resolution
   of short range conflict to permit proper MPR selection.

   Hence MAD messages are sent only in a limited local area, to
   guarantee proper MPR selection, at limited cost; and longer range
   conflicts are detected by passive methods.

   For completing all theoretical conflict cases, and in order to
   accelerate the detection by passive methods, in the even rarer case
   when the topology is symmetric, and nodes in conflict have identical
   message sequence numbers, we suggest that one bit somewhere in the
   message may be set randomly in the message (or based on node
   identifier): this gives an additional 50% chance of resolving the
   conflict at each generated message. (such a bit that might be set, is
   the last bit of the message sequence number).










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4.  Duplicate Address Detection Algorithms

4.1  Overview of the Different Solutions

   In order to detect address conflicts, each node diffuses periodically
   a special message that we call a MAD for ``Multiple Address
   Declaration'' to the entire network[14].  This control packet
   includes the node addresses and the node identifier.

   The node identifier is a sequence of bits of fixed length L which is
   randomly generated.  Hence we are using the standard idea that the
   probability of two nodes having the same node identifier is low, and
   the probability of at least one address collision with N nodes, which
   is the well known ``birthday problem'', can be set arbitrarily low by
   choosing a large enough value of L (eight bytes are enough to code
   the random identifier if we consider a network with a maximum of
   10000 nodes [13] [16]).  The MAD message format is depicted in the
   Appendix A

   A node detects an address conflict when it receives an MAD message
   having the same address as its own, but with a different identifier.
   These situations may happen during network mergers.  Actually other
   nodes will detect the conflict.  These nodes could announce the
   conflict using a special control message.  However this approach may
   induce broadcast storm since many nodes may announce the conflict and
   special care must be taken to avoid this effect.  For that reason we
   do not recommend this way.  An efficient manner to notify the address
   duplication to the nodes in conflict, consists in allowing the MAD
   packets to reach all the nodes in the network.

   Depending on which routing protocol is actually used, the MAD
   messages may be optimized in several kind of ways.  Several cases may
   be identified:

   o  OLSR [12]

   o  OLSRv2 [6]

   o  A protocol with support for an MPR-based flooding (such as [7] and
      [8])

   o  A protocol without an MPR-based optimization

   In the last case, if the protocol has no MPR-based optimization, the
   sending of MAD messages is done with the default of using pure
   flooding.  Additionally, whenever OLSR is not used, the MAD messages
   must be encapsulated in proper packets.




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   Otherwise: when MPR-based flooding is present, to save channel
   bandwidth the MAD packets should be broadcasted using this MPR-based
   flooding (either as a MPR-CDS or a genuine MPR flooding).  Then, of
   course, MAD messages are used in order to resolve conflicts, but
   conflicts themselves can lead to improper MPR selection.  Hence a few
   theoretical situations result some conflicts may not be resolved.
   This is addressed by special relaying rules for MPR-flooding, and
   three different approaches:

   o  In first one, designed for OLSR, we suggest to ignore the MPR
      mechanism for MAD relaying in the one-hop neighborhood and
      instead, the MAD messages are repeated by all neighbors (one-hop
      pure flooding).  Moreover special rules for address conversion are
      introduced when using the content of MAD messages.  One-hop pure
      flooding is sufficient for OLSR, hence the overhead is limited.

   o  The second one focuses on protocols different from OLSRv1: for
      MPR-based flooding protocols, and for OLSRv2, it is necessary that
      MAD messages are repeated by neighbors and also 2-hop neighbors.
      This method is a derivative of the previous algorithm, and is
      slightly more expensive, but more general.

   o  In the third one, MAD messages are also relayed by one-hop
      neighbors, as in the first approach.  Moreover, we also modify the
      MPR election algorithm of OLSR.  The calculation will be based on
      node identifiers to guarantee the uniqueness of the direct
      neighbors and the 2-hop neighbors.  This leads to a correct MPR
      set, hence, ensures that the MAD messages reach all the nodes.


4.2  First approach

   This approach is based on new rules for MPR flooding for MAD message
   (details are given in Appendix B).  The proof of correctness of this
   algorithm is given in [15] (including cases with multiple interfaces
   and multiple conflicts).  The two rules are:

4.2.1  Rule 1

   When a node X receives a MAD message and if node X has a symmetric or
   asymmetric link with a node Y with the same main address as the one
   contained in the MAD message, then node X relays this MAD message.
   When relaying the MAD message the Hop-Count field is set to 1.

4.2.2  Rule 2

   When a node X receives a HELLO message from a node Y, this HELLO
   contains interface addresses of 2-hop neighbors of X(1-hop neighbors



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   of Y).  To convert such addresses into main addresses the node X uses
   MAD messages that are relayed by Y. The rule 2 will actually avoid
   inconsistent main address conversions for 2-hop neighbors.  This is
   essential in the case of nodes with multiple interfaces.

4.3  Second approach

   In this approach, it is assumed that the rule 2 of the first approach
   can no longer be applied, because, for instance, the protocol does
   not use or has not MID/MAD messages.  In this case, the rule 2 is
   replaced the rule 2B, and the details are easily derived from
   Appendix B:

4.3.1  Rule 2B

   When a node X receives a MAD message, which it has not already
   retransmitted, with a hop count field equal to one, it relays it.
   The rule 2B will actually make all the 2-hop neighbors retransmit the
   message.

4.4  Third approach

   An issue with this first approach is that the conflicts at 2-hop must
   be resolved before one can be sure that the MAD messages are
   successfully transmitted within the entire network.  An ideal
   property would be that the MAD messages reach all the nodes in the
   network irrespectively of potential address duplications.  This
   property can be achieved if the MPR flooding continues to work in
   presence of address duplication.  A solution is then to base the
   selection of MPR not on addresses but on node identifiers.  With the
   assumption that node identifiers are globally unique in the network,
   one can be sure that there will not be identifier duplications at two
   hops of a given node and thus the selection of MPRs will be correct.
   This solution can be simply implemented, the selection of the MPRs
   must follow the principle defined in the OLSR protocol except that
   the base for the selection must be the node identifiers i.e. the
   2-hop coverage must be considered not on the addresses but on the
   node identifiers.

   This is achieved in this section by providing an alternative to the
   second rule.  The Rule 2 is replaced by a Rule 2C:

4.4.1  Rule 2C

   The MPR calculation is modified, by using node identifiers.  Each
   address is converted to a node identifier (using a method described
   later): as a result the node computing its MPR set, has its 1-hop and
   2-hop topology represented by links between node identifiers.



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   Details about applying rule 2C in practice are found in Appendix C.


















































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5.  IANA Considerations

   One new type of control message is defined in this protocol, for MAD
   messages.















































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6.  Security Considerations

   This memo does not specify any security considerations.
















































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Appendix A.  MAD Message Format

   An example of MAD message format is depicted in the following figure

     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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     |                   Originator node identifier                  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     OLSR Interface Address                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                     OLSR Interface Address                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                              ...                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                 Figure 1

   An alternative is to prepend an "Originator node identifier" OLSR
   message, to MeID messages






























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Appendix B.  DAD-MPR flooding algorithm

   Let us recall the assumptions here.  Each node A periodically sends a
   message M including:

   o  The originator address of A, Orig_A, in the OLSR message header.

   o  The list of interface addresses of node A in the message it self.

   o  The message sequence number, mssn, in the OLSR message header.

   o  The node identifier ID_A (a string of bits) in the message itself.

   The message is propagated by MPR flooding to the other nodes ; but
   for DAD-MPR Flooding, the duplicate table of OLSR is modified, so
   that it also includes the node identifier list in the duplicate
   tuple.  That is, a duplicate tuple, includes the following
   information:

   o  The originator address (as in OLSR standard duplicate table).

   o  The message sequence number (as in OLSR standard duplicate table).

   o  The list of node identifiers.

   o  The list of interface addresses on which the MAD message was
      received.

   The detailed algorithm for DAD-MPR Flooding is the following:

   o  When a node B receives a MAD message M on its interface B(i) from
      node C with originator Orig_A, with message sequence number mssn,
      and with node identifier ID_A, it performs the following tasks:

      1.  If a duplicate tuple exists with the same originator Orig_A,
          the same message sequence number mssn, the ID_A is in the list
          of node identifiers, and the interface address of B(i) is in
          the list of interface addresses on which the message has
          already been received, Then, the message is ignored (it has
          already been processed).  The algorithm stops here.

      2.  Else one of the following situations occurs :

          1.  A duplicate tuple exists with the same originator Orig_A,
              the same message sequence number mssn, ID_A is in the list
              of node identifiers, but the address of B(i) is not in the
              list of interface addresses on which the MAD message has
              already been received: then, the message must be



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              processed.  The address of B(i) is added to the list of
              interface addresses on which the message has already been
              received.

          2.  A duplicate tuple exists with the same originator Orig_A
              and the same message sequence number, but ID_A is not in
              the list of node identifiers: then, a conflict is detected
              (address Orig_A is duplicated).  ID_A is added to the list
              of node identifiers.

          3.  A duplicate tuple exists with the same originator Orig_A,
              but with a different message sequence number and ID_A is
              not in the list of node identifiers: then, a conflict is
              detected (address Orig_A is duplicated).  A duplicate
              tuple is created with the originator address, message
              sequence number and list of node identifiers containing
              only ID_A.

          4.  No duplicate tuple exists.  A new one is created with the
              originator address Orig_A, message sequence number mssn,
              list of interface addresses on which the MAD message has
              already been received containing only the address of B(i),
              and list of node identifiers containing only ID_A.

      3.  The MAD messages should be relayed if one or more of the
          following rules are met:

          1.  C had chosen this current receiving node, B, as an MPR.

          2.  Node B has a symmetric or asymmetric link with a node Y
              with the same main address as the one contained in the MAD
              message M. In such a case, the Hop-Count field is set to 1
              before message M retransmission.

   o  When a node X receives a HELLO message from a node Y, this HELLO
      contains interface addresses of 2-hop neighbors of X. The node X
      uses MAD messages relayed by Y to convert such addresses into main
      addresses.













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Appendix C.  Precisions for third approach

   The goal is to obtain the one hop neighborhood and the two-hop
   neighborhood with node identifiers in place of addresses.

   Converting main addresses of neighbor to node identifiers is easily
   done: when receiving the MAD messages from neighbors, the main
   address can be identified to be the address of a neighbor, and the
   node identifier is given.  Hence the node may record the information
   mapping main addresses of neighbors to their identifiers.

   Converting main addresses of two-hop neighbors to node identifiers is
   less direct: however the information obtained thanks to the fact that
   MAD messages from two-hop neighbors are always retransmitted by one-
   hop neighbors.  Such MAD messages are identified by the fact that
   they arrive with a hop count field (corrected by Rule 1 is
   necessary), equal to 1 ; in the following, they are called two-hop
   MAD messages.  The receiver node can thus maintain the information
   Two-Hop Identifier Table: (neighbor address, two-hop neighbor
   addresses list, two-hop neighbor identifier) in or in addition to,
   the MID/MAD information base.  Now taking advantage of the fact that
   conflicts at distance 1 to 3 are resolved anyway by Rule 1, it is
   know that one neighbor will retransmit neighbor MAD message (two-hop
   MAD messages for the receiver) that have all different addresses:
   otherwise there would be a 2-hop conflict, necessarily resolved.
   Thus the mapping deduced from the Two-Hop Identifier Table, (neighbor
   main address, two-hop neighbor main address) -->two-hop neighbor
   identifier is unique (and corresponds to reality).

   Note also, that the information containted in the two-hop identifier
   table, should be also used for processing Hello messages (converting
   interface addresses to main addresses) so that the two-hop neighbor
   main address in the two-hop tuple is the actual main address.


















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7.  References

7.1  Normative References

7.2  Informative References

   [1]   Bernardos, C. and M. Calderon, "Survey of IP address
         autoconfiguration mechanisms for MANETs",
         draft-bernardos-manet-autoconf-survey-00 (work in progress),
         July 2005.

   [2]   Clausen, T. and E. Baccelli, "Simple MANET Address
         Autoconfiguration", draft-clausen-manet-address-autoconf-00
         (work in progress), February 2005.

   [3]   Ruffino, S., "Connectivity Scenarios for MANET",
         draft-ruffino-conn-scenarios-00 (work in progress),
         February 2005.

   [4]   Mase, K. and C. Adjih, "No Overhead Autoconfiguration OLSR",
         draft-mase-manet-autoconf-noaolsr-00 (work in progress),
         May 2005.

   [5]   Ruffino, S. and P. Stupar, "Automatic configuration of IPv6
         addresses for nodes in a MANET with multiple  gateways",
         draft-ruffino-manet-autoconf-multigw-00 (work in progress),
         June 2005.

   [6]   Clausen, T., "The Optimized Link-State Routing Protocol version
         2", draft-clausen-manet-olsrv2-00 (work in progress),
         July 2005.

   [7]   Perkins, C., "Multicast With Minimal Congestion Using Connected
         Dominating Sets", draft-perkins-manet-smurf-00 (work in
         progress), July 2005.

   [8]   Macker, J., "Simplified Multicast Forwarding for MANET",
         draft-ietf-manet-smf-00 (work in progress), July 2005.

   [9]   Weniger, K., "Passive Duplicate Address Detection in Mobile Ad
         hoc  Networks", March 2003.

   [10]  "R.  Droms, Ed.,J.  Bound, B.  Volz, T.  Lemon, C.  Perkins, M.
         Carney, 'Dynamic Host Configuration Protocol for IPv6
         (DHCPv6)', IETF RFC 3315, July 2003".

   [11]  "S.  Thomson, T.  Narten, 'IPv6 Stateless Address
         Autoconfiguration', IETF RFC 2462, December 1998".



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   [12]  "T.  Clausen, Ed., P.  Jacquet, Ed., 'Optimized Link State
         Routing Protocol',  Request for Comments (Experimental) 3626,
         Internet  Engineering Task Force, October 2003".

   [13]  "S.Boudjit, A.  Laouiti, P.  Muhlethaler, C.  Adjih, 'Duplicate
         address detection and autoconfiguration in OLSR', INRIA
         Research Report-5475, Jan 2005".

   [14]  "A.  Laouiti, S.  Boudjit, P.  Minet and C.  Adjih, 'OLSR for
         IPv6 networks', Proceedings of Med-Hoc-Net, June 2004,Bodrum,
         Turkey".

   [15]  "C. Adjih, S.Boudjit, P. Jacquet, A.  Laouiti, P.  Muhlethaler,
         'An Advanced Configuration and Duplicate Address Detection
         mechanism for a multi-interface OLSR Network', INRIA Research
         Report, Jul 2005".

   [16]  "S. Boudjit, C. Adjih, A. Laouiti, P. Muhlethaler,'Duplicate
         address detection  and autoconfiguration in OLSR', Proceedings
         of IEEE SAWN 2005, May 2005, Maryland,  USA".


Authors' Addresses

   Cedric Adjih
   INRIA Rocquencourt, France
   Project HIPERCOM
   Domaine de Voluceau -Rocquencourt
   BP 105
   Le Chesnay  78153 cedex
   France

   Phone: +33 1 3963 5215
   Email: cedric.adjih@inria.fr


   Saadi Boudjit
   INRIA Rocquencourt, France
   Project HIPERCOM
   Domaine de Voluceau -Rocquencourt
   BP 105
   Le Chesnay  78153 cedex
   France

   Phone: +33 1 3963 5039
   Email: saadi.boudjit@inria.fr





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   Philippe Jacquet
   INRIA Rocquencourt, France
   Project HIPERCOM
   Domaine de Voluceau -Rocquencourt
   BP 105
   Le Chesnay  78153 cedex
   France

   Phone: +33 1 3963 5263
   Email: philippe.jacquet@inria.fr


   Anis Laouiti
   INRIA Rocquencourt, France
   Project HIPERCOM
   Domaine de Voluceau -Rocquencourt
   BP 105
   Le Chesnay  78153 cedex
   France

   Phone: +33 1 3963 5088
   Email: anis.laouiti@inria.fr


   Paul Muhlethaler
   INRIA Rocquencourt, France
   Project HIPERCOM
   Domaine de Voluceau -Rocquencourt
   BP 105
   Le Chesnay  78153 cedex
   France

   Phone: +33 1 3963 5278
   Email: paul.muhlethaler@inria.fr


   Pr. Kenichi Mase
   Information and Communication Network Lab.,Niigata University
   Niigata University
   Niigata 950-2181,
   Japan

   Phone: +81 25 262 7446
   Email: mase@ie.niigata-u.ac.jp
   URI:   http://www.net.ie.niigata-u.ac.jp/






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