Asymmetric AODV-P2P-RPL in Low-Power and Lossy Networks (LLNs)
draft-satish-roll-aodv-rpl-01

ROLL                                                      S. Anamalamudi
Internet-Draft                                                  M. Zhang
Intended status: Standards Track                               AR. Sangi
Expires: February 4, 2017                            Huawei Technologies
                                                              C. Perkins
                                                               Futurewei
                                                             S.V.R.Anand
                                             Indian Institute of Science
                                                          August 3, 2016

     Asymmetric AODV-P2P-RPL in Low-Power and Lossy Networks (LLNs)
                     draft-satish-roll-aodv-rpl-01

Abstract

   Route discovery for symmetric and asymmetric Point-to-Point (P2P)
   traffic flows is desired in Low power and Lossy Networks (LLNs).  For
   that purpose, this document specifies a reactive P2P route discovery
   mechanism for hop-by-hop routing (storing mode) based on Ad Hoc On-
   demand Distance Vector Routing (AODV) based RPL protocol.  Two
   separate Instances are used to construct directional paths in case
   some of the links between source and target node are asymmetric.

Status of This Memo

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   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on February 4, 2017.

Copyright Notice

   Copyright (c) 2016 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

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   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Overview of AODV-RPL  . . . . . . . . . . . . . . . . . . . .   5
   4.  AODV-RPL Mode of Operation (MoP)  . . . . . . . . . . . . . .   5
   5.  RREQ Message  . . . . . . . . . . . . . . . . . . . . . . . .   8
   6.  RREP Message  . . . . . . . . . . . . . . . . . . . . . . . .   9
   7.  Gratuitous RREP . . . . . . . . . . . . . . . . . . . . . . .  10
   8.  Operation of Trickle Timer  . . . . . . . . . . . . . . . . .  11
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
     9.1.  New Mode of Operation: AODV-RPL . . . . . . . . . . . . .  11
     9.2.  AODV-RPL Options: RREQ and RREP . . . . . . . . . . . . .  11
   10. Security Considerations . . . . . . . . . . . . . . . . . . .  12
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     11.2.  Informative References . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   RPL[RFC6550], the IPv6 distance vector routing protocol for Low-power
   and Lossy Networks (LLNs), is designed to support multiple traffic
   flows through a root-based Destination-Oriented Directed Acyclic
   Graph (DODAG).  For traffic flows between routers within the DODAG
   (i.e., Point-to-Point (P2P)), this means that data packets either
   have to traverse the root in non-storing mode (source routing), or
   traverse a common ancestor in storing mode (hop-by-hop routing).
   Such P2P traffic is thereby likely to flow along sub-optimal routes
   and may suffer severe traffic congestion near the DAG root [RFC6997],
   [RFC6998].

   To discover optimal paths for P2P traffic flows in RPL, P2P-RPL
   [RFC6997] specifies a temporary DODAG where the source acts as
   temporary root.  The source initiates "P2P Route Discovery mode (P2P-
   RDO)" with an address vector for both non-storing mode (H=0) and
   storing mode (H=1).  Subsequently, each intermediate router adds its
   IP address and multicasts the P2P-RDO message, until the message
   reaches the target node (TargNode).  TargNode sends the "Discovery
   Reply" option.  P2P-RPL is efficient for source routing, but much

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   less efficient for hop-by-hop routing due to the extra address vector
   overhead.  In fact, when the P2P-RDO message is being multicast from
   the source hop-by-hop, receiving nodes are able to determine a next
   hop towards the source in symmetric links.  When TargNode
   subsequently replies to the source along the established forward
   route, receiving nodes can determine the next hop towards TargNode.
   In other words, it is efficient to use only routing tables for P2P-
   RDO message instead of "Address vector" for hop-by-hop routes (H=1)
   in symmetric links.

   RPL and P2P-RPL both specify the use of a single DODAG in networks of
   symmetric links.  But, application-specific routing requirements that
   are defined in IETF ROLL Working Group [RFC5548], [RFC5673],
   [RFC5826] and [RFC5867] may need routing metrics and constraints
   related to asymmetric bidirectional links.  For this purpose,
   [I-D.thubert-roll-asymlink] describes bidirectional asymmetric links
   for RPL [RFC6550] with Paired DODAGs, for which the DAG root
   (DODAGID) is common for two Instances.  This can satisfy application-
   specific routing requirements for bidirectional asymmetric links in
   base RPL [RFC6550].  P2P-RPL for Paired DODAGs, on the other hand,
   requires two DAG roots: one for the source and another for the target
   node due to temporary DODAG formation.  For networks composed of
   bidirectional asymmetric links (see Section 4), AODV-RPL specifies
   P2P route discovery, utilizing RPL with a new MoP.  AODV-RPL makes
   use of two multicast messages to discover possibly asymmetric routes.
   AODV-RPL eliminates the need for address vector control overhead,
   significantly reducing the control packet size which is important for
   Constrained LLN networks.  Both discovered routes meet the
   application specific metrics and constraints that are defined in the
   Objective Function for each Instance [RFC6552].

2.  Terminology

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

   AODV
      Ad Hoc On-demand Distance Vector Routing[RFC3561].

   AODV-Instance
      Either the RREQ-Instance or RREP-Instance

   Bi-directional Asymmetric Link
      A link that can be used in both directions but with different link
      characteristics (see [I-D.thubert-roll-asymlink]).

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   DODAG RREQ-Instance (or simply RREQ-Instance)
      AODV Instance built using the RREQ option; used for control
      transmission from OrigNode to TargNode, thus enabling data
      transmission from TargNode to OrigNode.

   DODAG RREP-Instance (or simply RREP-Instance)
      AODV Instance built using the RREP option; used for control
      transmission from TargNode to OrigNode thus enabling data
      transmission from OrigNode to TargNode.

   downstream
      Routing along the direction from OrigNode to TargNode.

   hop-by-hop routing
      Routing when each node stores routing information about the next
      hop.

   OrigNode
      The IPv6 router (Originating Node) initiating the AODV-RPL route
      discovery to obtain a route to TargNode.

   Paired DODAGs
      Two DODAGs for a single application.

   P2P
      Point-to-Point -- in other words, not constrained to traverse the
      global DODAG root.

   RREP message
      An AODV-RPL MoP DIO message containing the RREP option

   RREQ message
      An AODV-RPL MoP DIO message containing the RREQ option

   source routing
      The mechanism by which the source supplies the complete route
      towards the target node along with each data packet [RFC6997].

   TargNode
      The IPv6 router (Target Node) for which OrigNode requires a route
      and initiates Route Discovery within the LLN network.

   upstream
      Routing along the direction from TargNode to OrigNode.

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3.  Overview of AODV-RPL

   With AODV-RPL, routes from OrigNode to TargNode within the LLN
   network established are "on-demand".  In other words, the route
   discovery mechanism in AODV-RPL is invoked reactively when OrigNode
   has data for delivery to the TargNode but existing routes do not
   satisfy the application's requirements.  The routes discovered by
   AODV-RPL are point-to-point; in other words the routes are not
   constrained to traverse a global DAG.  Unlike base RPL [RFC6550] and
   P2P-RPL [RFC6997], AODV-RPL can enable asymmetric communication paths
   in networks with bidirectional asymmetric links.  For this purpose,
   AODV-RPL enables discovery of two routes: namely, one from OrigNode
   to TargNode, and another from TargNode to OrigNode.  When possible,
   AODV-RPL also enables symmetric routing along Paired DODAGs (see
   Section 4).

4.  AODV-RPL Mode of Operation (MoP)

   In AODV-RPL, route discovery is initiated by forming a temporary DAG
   rooted at the OrigNode.  Paired DODAGs (Instances) are constructed
   according to a new AODV-RPL Mode of Operation (MoP) during route
   formation between the OrigNode and TargNode.  The RREQ-Instance is
   formed by route control messages from OrigNode to TargNode whereas
   the RREP-Instance is formed by route control messages from TargNode
   to OrigNode (as shown in Figure 2).  Intermediate routers join the
   Paired DODAGs based on the rank as calculated from the DIO message.
   Henceforth in this document, the RREQ-Instance message means the
   AODV-RPL DIO message from OrigNode to TargNode, containing the RREQ
   option.  Similarly, the RREP-Instance means the AODV-RPL DIO message
   from TargNode to OrigNode, containing the RREP option.  Subsequently,
   the RREQ-Instance is used for data transmission from TargNode to
   OrigNode and RREP-Instance is used for Data transmission from
   OrigNode to TargNode.

   The AODV-RPL Mode of Operation defines a new bit, the Symmetric bit
   ('S'), which is added to the base DIO message as illustrated in
   Figure 1.  OrigNode sets the the 'S' bit to 1 in the RREQ-Instance
   message when initiating route discovery.

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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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | RPLInstanceID |Version Number |             Rank              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |G|0| MOP | Prf |     DTSN      |S|    Flags    |   Reserved    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       +                                                               +
       |                                                               |
       +                            DODAGID                            +
       |                                                               |
       +                                                               +
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Option(s)...

     Figure 1: DIO modification to support asymmetric route discovery

   A device originating a AODV-RPL message supplies the following
   information in the DIO header of the message:

   'S' bit

      Symmetric bit in the DIO base object

   MOP

      MOP operation in the DIO object MUST be set to "5(TBD1)" for AODV-
      RPL DIO messages

   RPLInstanceID

      RPLInstanceID in the DIO object MUST be the InstanceID of AODV-
      Instance.

   DODAGID

      DODAGID in the DIO object MUST be the IPv6 address of the device
      that initiates the AODV-Instance.

   Rank

      Rank in the DIO object MUST be the the rank of the AODV-Instance

   Metric Container Options

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      AODV-Instance messages MAY carry one or more Metric Container
      options to indicate the relevant routing metrics

   The 'S' bit is set to mean that the route is symmetric.  If the RREQ-
   Instance arrives over an interface that is known to be symmetric, and
   the 'S' bit is set to 1, then it remains set at 1, as illustrated in
   Figure 2.

    In this figure:
           S := OrigNode;  R := Intermediate nodes;  D := TargNode

                R---------R---------R---------R
                |<--S=1-->|<--S=1-->|<--S=1-->|
                |         |         |         |
            <--S=1-->     |         |     <--S=1-->
                |         |         |         |
                |         |         |         |
      S---------R---------R---------R---------R---------R---------D
       <--S=1-->|         |         |         |<--S=1-->|<--S=1-->|
                |         |         |         |         |         |
                |         |         |         |         |         |
                R---------R---------R---------R---------R---------R

        >---- RREQ-Instance (Control: S-->D;  Data: D-->S) ------->
        <---- RREP-Instance (Control: D-->S;  Data: S-->D) -------<

            Figure 2: AODV-RPL with Symmetric Paired Instances

   If the RREQ-Instance arrives over an interface that is not known to
   be symmetric, or is known to be asymmetric, the 'S' bit is set to be
   0.  Moreover, if the 'S' bit arrives already set to be '0', it is set
   to be '0' on retransmission (Figure 3).  Based on the 'S' bit
   received in RREQ-Instance, the TargNode decides whether or not the
   route is symmetric before transmitting the RREP-Instance message
   upstream towards the OrigNode.  The exact metric used to set the "S"
   bit to be "1" (symmetric) or "0" (asymmetric) is out-of-scope of this
   specification.

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               R---------R--------R--------R
               | --S=1-->|--S=1-->|--S=0-->|
               |         |        |        |
            --S=1-->     |        |     --S=0-->
               |         |        |        |
       --S=1-->|         |        |        |
      S--------R---------R--------R--------R--------R---------D
       <--S=0--|         |        |        |--S=0-->| --S=0-->|
               |         |        |        |        |         |
           <--S=0--      |        |        |        |     <--S=0--
               |         |        |        |        |         |
               | <--S=0--|<--S=0--|<--S=0--|<--S=0--|<--S=0-- |
               R---------R--------R--------R--------R---------R

        >---- RREQ-Instance (Control: S-->D;  Data: D-->S) ------->
        <---- RREP-Instance (Control: D-->S;  Data: S-->D) -------<

            Figure 3: AODV-RPL with Asymmetric Paired Instances

5.  RREQ Message

       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      |      Orig SeqNo       |      Dest SeqNo       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       |                     TargNode IPv6 Address                     |
       |                                                               |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 4: DIO RREQ option format for AODV-RPL MoP

   OrigNode supplies the following information in the RREQ option of the
   RREQ-Instance message:

   Type

      The type of the RREQ option (see Section 9.2)

   Orig SeqNo

      Sequence Number of OrigNode.

   Dest SeqNo

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      If nonzero, the last known Sequence Number for TargNode for which
      a route is desired.

   TargNode IPv6 Address

      IPv6 address of the TargNode that receives RREQ-Instance message.
      This address MUST be in the RREQ option (see Figure 4) of AODV-
      RPL.

   In order to establish the upstream route from TargNode to OrigNode,
   OrigNode multicasts the RREQ-Instance message (see Figure 4) to its
   one-hop neighbours.  Each intermediate node R_i computes the rank for
   RREQ-Instance and creates a routing table entry for the upstream
   route towards the source if the routing metrics/constraints are
   satisfied.  For this purpose R_i must use the asymmetric link metric
   measured in the upstream direction, from R_i to its upstream neighbor
   that multicasted the RREP-Instance message.

   If the path towards TargNode is not known, the intermediate node
   multicasts the RREQ-Instance message with updated rank to its next-
   hop neighbors until the message reaches to TargNode (Figure 2).
   Based on the 'S' bit in the received RREQ message, the TargNode will
   decide whether to unicast or multicast the RREP message back to
   OrigNode.

   As described in Section 7, in certain circumstances R_i MAY unicast a
   Gratuitous RREP towards OrigNode, thereby helping to minimize
   multicast overhead during the Route Discovery process.

6.  RREP Message

   The TargNode supplies the following information in the RREP message:

      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      |      Dest SeqNo       |Prefix Sz|G| Reserved  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                                                               |
     |                     TargNode IPv6 Address                     |
     |                                                               |
     |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 5: DIO RREP option format for AODV-RPL MoP

   Type

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      The type of the RREP option (see Section 9.2)

   Dest SeqNo

      The Sequence Number for the TargNode for which a route is
      established.

   Prefix Sz

      The size of the prefix which the route to the TargNode is
      available.  This allows routing to other nodes on the same subnet
      as the TargNode.

   'G' bit

      (see Section 7)

   TargNode IPv6 Address

      IPv6 address of the TargNode that receives RREP-Instance message.
      This address MUST be in the RREP option

   The OrigNode IP address is available as the DODAGID in the DIO base
   message (see Figure 1).  When TargNode receives a RREQ message with
   the 'S' bit set to 1 (as illustrated in Figure 2), it unicasts the
   RREP message with the 'S' bit set to 1.  In this case, route control
   messages and application data between OrigNode and TargNode for both
   RREQ-Instance and RREP-Instance are transmitted along symmetric
   links.

   When (as illustrated in Figure 3) the TargNode receives RREQ message
   with the 'S' bit set to 0, it also multicasts the RREP message with
   the 'S' bit set to 0.  Intermediate nodes create a routing table
   entry for the path towards the TargNode while processing the RREP
   message to OrigNode.  Once OrigNode receives the RREP message, it
   starts transmitting application data to TargNode along the path as
   discovered through RREP messages.  Similarly, application data from
   TargNode to OrigNode is transmitted through the path that is
   discovered from RREQ message.

7.  Gratuitous RREP

   Under some circumstances, an Intermediate Node that receives a RREQ
   message MAY transmit a "Gratuitous" RREP message back to OrigNode
   instead of continuing to multicast the RREQ message towards TargNode.
   For these circumstances, the 'G' bit of the RREP option is provided
   to distinguish the Gratuitous RREP sent by the Intermediate node from
   the RREP sent by TargNode.

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   When an Intermediate node R receives a RREQ message and has recent
   information about the cost of an upstream route from TargNode to R,
   then R MAY unicast the Gratuitous RREP (GRREP) message to OrigNode.
   R determines whether its information is sufficiently recent by
   comparing the value it has stored for the Sequence Number of TargNode
   against the DestSeqno in the incoming RREQ message.  R also must have
   information about the metric information of the upstream route from
   TargNode.  The GRREP message MUST have PrefixSz == 0 and the 'G' bit
   set to 1.  R SHOULD also unicast the RREQ message to TargNode, to
   make sure that TargNode will have a route to OrigNode.

8.  Operation of Trickle Timer

   The trickle timer operation to control RREQ-Instance/RREP-Instance
   multicast is similar to that in P2P-RPL [RFC6997].

9.  IANA Considerations

9.1.  New Mode of Operation: AODV-RPL

   IANA is required to assign a new Mode of Operation, named "AODV-RPL"
   for Point-to-Point(P2P) hop-by-hop routing under the RPL registry.
   The value of TBD1 is assigned from the "Mode of Operation" space
   [RFC6550].

            +-------------+---------------+---------------+
            |    Value    |  Description  |   Reference   |
            +-------------+---------------+---------------+
            |   TBD1 (5)  |   AODV-RPL    | This document |
            +-------------+---------------+---------------+

                        Figure 6: Mode of Operation

9.2.  AODV-RPL Options: RREQ and RREP

   Two entries are required for new AODV-RPL options "RREQ-Instance" and
   "RREQ-Instance", with values of TBD2 (0x0a) and TBD3 (0x0b) from the
   "RPL Control Message Options" space [RFC6550].

             +-------------+---------------------+---------------+
             |     Value   |       Meaning       |   Reference   |
             +-------------+---------------------+---------------+
             |  TBD2(0x0a) |     RREQ Option     | This document |
             +-------------+---------------------+---------------+
             |  TBD3(0x0b) |     RREP Option     | This document |
             +-------------+---------------------+---------------+

                        Figure 7: AODV-RPL Options

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10.  Security Considerations

   This document does not introduce additional security issues compared
   to base RPL.  For general RPL security considerations, see [RFC6550].

11.  References

11.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC3561]  Perkins, C., Belding-Royer, E., and S. Das, "Ad hoc On-
              Demand Distance Vector (AODV) Routing", RFC 3561,
              DOI 10.17487/RFC3561, July 2003,
              <http://www.rfc-editor.org/info/rfc3561>.

   [RFC5548]  Dohler, M., Ed., Watteyne, T., Ed., Winter, T., Ed., and
              D. Barthel, Ed., "Routing Requirements for Urban Low-Power
              and Lossy Networks", RFC 5548, DOI 10.17487/RFC5548, May
              2009, <http://www.rfc-editor.org/info/rfc5548>.

   [RFC5673]  Pister, K., Ed., Thubert, P., Ed., Dwars, S., and T.
              Phinney, "Industrial Routing Requirements in Low-Power and
              Lossy Networks", RFC 5673, DOI 10.17487/RFC5673, October
              2009, <http://www.rfc-editor.org/info/rfc5673>.

   [RFC5826]  Brandt, A., Buron, J., and G. Porcu, "Home Automation
              Routing Requirements in Low-Power and Lossy Networks",
              RFC 5826, DOI 10.17487/RFC5826, April 2010,
              <http://www.rfc-editor.org/info/rfc5826>.

   [RFC5867]  Martocci, J., Ed., De Mil, P., Riou, N., and W. Vermeylen,
              "Building Automation Routing Requirements in Low-Power and
              Lossy Networks", RFC 5867, DOI 10.17487/RFC5867, June
              2010, <http://www.rfc-editor.org/info/rfc5867>.

   [RFC6550]  Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J.,
              Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur,
              JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
              Low-Power and Lossy Networks", RFC 6550,
              DOI 10.17487/RFC6550, March 2012,
              <http://www.rfc-editor.org/info/rfc6550>.

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   [RFC6552]  Thubert, P., Ed., "Objective Function Zero for the Routing
              Protocol for Low-Power and Lossy Networks (RPL)",
              RFC 6552, DOI 10.17487/RFC6552, March 2012,
              <http://www.rfc-editor.org/info/rfc6552>.

   [RFC6997]  Goyal, M., Ed., Baccelli, E., Philipp, M., Brandt, A., and
              J. Martocci, "Reactive Discovery of Point-to-Point Routes
              in Low-Power and Lossy Networks", RFC 6997,
              DOI 10.17487/RFC6997, August 2013,
              <http://www.rfc-editor.org/info/rfc6997>.

   [RFC6998]  Goyal, M., Ed., Baccelli, E., Brandt, A., and J. Martocci,
              "A Mechanism to Measure the Routing Metrics along a Point-
              to-Point Route in a Low-Power and Lossy Network",
              RFC 6998, DOI 10.17487/RFC6998, August 2013,
              <http://www.rfc-editor.org/info/rfc6998>.

11.2.  Informative References

   [I-D.thubert-roll-asymlink]
              Thubert, P., "RPL adaptation for asymmetrical links",
              draft-thubert-roll-asymlink-02 (work in progress),
              December 2011.

Authors' Addresses

   Satish Anamalamudi
   Huawei Technologies
   No. 156 Beiqing Rd. Haidian District
   Beijing  100095
   China

   Email: satishnaidu80@gmail.com

   Mingui Zhang
   Huawei Technologies
   No. 156 Beiqing Rd. Haidian District
   Beijing  100095
   China

   Email: zhangmingui@huawei.com

Anamalamudi, et al.     Expires February 4, 2017               [Page 13]
Internet-Draft         draft-satish-ROLL-AODV-RPL            August 2016

   Abdur Rashid Sangi
   Huawei Technologies
   No.156 Beiqing Rd. Haidian District
   Beijing  100095
   P.R. China

   Email: rashid.sangi@huawei.com

   Charles E. Perkins
   Futurewei
   2330 Central Expressway
   Santa Clara  95050
   Unites States

   Email: charliep@computer.org

   S.V.R Anand
   Indian Institute of Science
   Bangalore  560012
   India

   Email: anand@ece.iisc.ernet.in

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