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Network Working Group                                       M. Boucadair
Internet-Draft                                              C. Jacquenet
Intended status: Experimental                             France Telecom
Expires: June 10, 2016                                       D. Behaghel
                                                               OneAccess
                                                                S. Secci
                                 Universite Pierre et Marie Curie (UPMC)
                                                           W. Henderickx
                                                          Alcatel-Lucent
                                                                 R. Skog
                                                                Ericsson
                                                        December 8, 2015


An MPTCP Option for Network-Assisted MPTCP Deployments: Plain Transport
                                  Mode
                  draft-boucadair-mptcp-plain-mode-06

Abstract

   One of the promising deployment scenarios for Multipath TCP (MPTCP)
   is to enable a Customer Premises Equipment (CPE) that is connected to
   multiple networks (e.g., DSL, LTE, WLAN) to optimize the usage of its
   network attachments.  Because of the lack of MPTCP support at the
   server side, some service providers now consider a network-assisted
   model that relies upon the activation of a dedicated function called
   MPTCP Concentrator.  This document focuses on a deployment scheme
   where the identity of the MPTCP Concentrator(s) is explicitly
   configured on connected hosts.

   This document specifies an MPTCP option that is used to avoid an
   encapsulation scheme between the CPE and the MPTCP Concentrator.
   Also, this document specifies how UDP traffic can be distributed
   among available paths without requiring any encapsulation scheme.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

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



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   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 June 10, 2016.

Copyright Notice

   Copyright (c) 2015 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
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Assumptions . . . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Introducing the MPTCP Plain Transport Mode  . . . . . . . . .   5
     4.1.  An Alternative to Encapsulation . . . . . . . . . . . . .   5
     4.2.  Plain Mode MPTCP Option . . . . . . . . . . . . . . . . .   6
     4.3.  Theory of Operation . . . . . . . . . . . . . . . . . . .   7
     4.4.  Flow Example  . . . . . . . . . . . . . . . . . . . . . .   8
   5.  UDP Traffic . . . . . . . . . . . . . . . . . . . . . . . . .   9
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13








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1.  Introduction

   One of the promising deployment scenarios for Multipath TCP (MPTCP,
   [RFC6824]) is to enable a Customer Premises Equipment (CPE) that is
   connected to multiple networks (e.g., DSL, LTE, WLAN) to optimize the
   usage of such resources, see for example [I-D.deng-mptcp-proxy] or
   [RFC4908].  This deployment scenario relies on MPTCP proxies located
   on both the CPE and network sides (Figure 1).  The latter plays the
   role of traffic concentrator.  A concentrator terminates the MPTCP
   sessions established from a CPE, before redirecting traffic into a
   legacy TCP session.

                         IP Network #1
    +------------+        _--------_    +------------+
    |            |       (e.g., LTE )   |            |
    |   CPE      +=======+          +===+            |
    | (MPTCP     |       (_        _)   |Concentrator|
    |  Proxy)    |         (_______)    | (MPTCP     |
    |            |                      |  Proxy)    |------> Internet
    |            |                      |            |
    |            |        IP Network #2 |            |
    |            |        _--------_    |            |
    |            |       ( e.g., DSL )  |            |
    |            +=======+           +==+            |
    |            |       (_        _)   |            |
    +-----+------+        (_______)     +------------+
          |
   ----CPE network----
          |
       end-nodes

                 Figure 1: "Network-Assisted" MPTCP Design

   Both implicit and explicit models are considered to steer traffic
   towards an MPTCP Concentrator.  This document focuses on the explicit
   model that consists in configuring explicitly the reachability
   information of the MPTCP concentrator on a host (e.g.,
   [I-D.boucadair-mptcp-dhc]).

   This specification assumes an MPTCP Concentrator is reachable through
   one or multiple IP addresses.  Also, it assumes the various network
   attachments provided to an MPTCP-enabled CPE are managed by the same
   administrative entity.  Additional assumptions are listed in
   Section 3.

   This document explains how a plain transport mode, where packets are
   exchanged between the CPE and the concentrator without requiring the




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   activation of any encapsulation scheme (e.g., IP-in-IP [RFC2473], GRE
   [RFC1701], SOCKS [RFC1928], etc.), can be enabled.

   Also, this document investigates an alternate track where UDP flows
   can be distributed among available paths without requiring any
   encapsulation scheme.

   The solution in this document does not require the modification of
   the binding information base (BIB) structure maintained by both the
   CPE and the Concentrator.  Likewise, this approach does not infer any
   modification of the Network Address Translator (NAT) functions that
   may reside in both the CPE and the device that embeds the
   concentrator.

   The solution also works properly when NATs are present in the network
   between the CPE and the Concentrator, unlike solutions that rely upon
   GRE tunneling.  Likewise, the solution accommodates deployments that
   involve CGN (Carrier Grade NAT) upstream the Concentrator.

2.  Terminology

   This document makes use of the following terms:

   o  Customer-facing interface: is an interface of the MPTCP
      Concentrator that is visible to a CPE and which is used for
      communication purposes between a CPE and the MPTCP Concentrator.

   o  MPTCP Proxy: is a software module that is responsible for
      transforming a TCP connection into an MPTCP connection, and vice
      versa.  Typically, an MPTCP proxy can be embedded in a CPE and/or
      a Concentrator.

   o  MPTCP leg: Refers to a network segment on which MPTCP is used to
      establish TCP connections.

   o  MPTCP Concentrator (or concentrator): refers to a functional
      element that is responsible for aggregating the traffic of a group
      of CPEs.  This element is located upstream in the network.  One or
      multiple concentrators can be deployed in the network side to
      assist MPTCP-enabled CPEs to establish MPTCP connections via
      available network attachments.

      On the uplink path, the concentrator terminates the MPTCP
      connections received from its customer-facing interfaces and
      transforms these connections into legacy TCP connections towards
      upstream servers.





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      On the downlink path, the concentrator turns the legacy server's
      TCP connection into MPTCP connections towards its customer-facing
      interfaces.

3.  Assumptions

   The following assumptions are made:

   o  The logic for mounting network attachments by a host is
      deployment- and implementation-specific and is out of scope of
      this document.
   o  The Network Provider that manages the various network attachments
      (including the concentrators) can enforce authentication and
      authorization policies using appropriate mechanisms that are out
      of scope of this document.
   o  Policies can be enforced by a concentrator instance operated by
      the Network Provider to manage both upstream and downstream
      traffic.  These policies may be subscriber-specific, connection-
      specific or system-wide.
   o  The concentrator may be notified about the results of monitoring
      (including probing) the various network legs to service a
      customer, a group of customers, a given region, etc.  No
      assumption is made by this document about how these monitoring
      (including probing) operations are executed.
   o  An MPTCP-enabled, multi-interfaced host that is directly connected
      to one or multiple access networks is allocated addresses/prefixes
      via legacy mechanisms (e.g., DHCP) supported by the various
      available network attachments.  The host may be assigned the same
      or distinct IP address/prefix via the various available network
      attachments.
   o  The location of the concentrator(s) is deployment-specific.
      Network Providers may choose to adopt centralized or distributed
      (even if they may not be present on the different network
      accesses) designs, etc.  Nevertheless, in order to take advantage
      of MPTCP, the location of the concentrator should not jeopardize
      packet forwarding performance for traffic sent from or directed to
      connected hosts.

4.  Introducing the MPTCP Plain Transport Mode

4.1.  An Alternative to Encapsulation

   The design option for aggregating various network accesses often
   relies upon the use of an encapsulation scheme (such as GRE) between
   the CPE and the Concentrator.  The use of encapsulation is motivated
   by the need to steer traffic through the concentrator and also to
   allow the distribution of UDP flows among the available paths without
   requiring any advanced traffic engineering tweaking technique in the



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   network side to intercept traffic and redirect it towards the
   appropriate concentrator.

   This document specifies another approach that relies upon plain
   transport mode between the CPE and the Concentrator.

   The use of a plain transport mode does not require the upgrade of any
   intermediate function (security, TCP optimizer, etc.) that may be
   located on-path.  Thus, the introduction of MPTCP concentrators in
   operational networks to operate plain mode does not add any extra
   complexity as far as the operation of possible intermediate functions
   is concerned.

4.2.  Plain Mode MPTCP Option

   The format of the Plain Mode MPTCP option is shown in Figure 2.

        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
       +---------------+---------------+-------+-------+---------------+
       |     Kind      |     Length    |SubType|D|U|       Flag Bits   |
       +---------------+---------------+-------+-------+---------------+
       |          Address (IPv4 - 4 octets / IPv6 - 16 octets)         |
       +-------------------------------+-------------------------------+
       |   Port (2 octets, optional)   |
       +-------------------------------+


                     Figure 2: Plain Mode MPTCP Option

   The description of the fields is as follows:

   o  Kind and Length: are the same as in [RFC6824].

   o  Subtype: to be defined by IANA (Section 6).

   o  D-bit (direction bit): This flag indicates whether the enclosed IP
      address (and a port number) reflects the source or destination IP
      address (and port).  When the D-bit is set, the enclosed IP
      address must be interpreted as the source IP address.  When the
      D-bit is unset, the enclosed IP address must be interpreted as the
      destination IP address.

   o  U-bit (UDP bit): The use of this flag is detailed in Section 5.

   o  The "Flag" bits are reserved bits for future assignment as
      additional flag bits.  These additional flag bits MUST each be set
      to zero and MUST be ignored upon receipt.




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   o  Address: Includes a source or destination IP address.  The address
      family is determined by the "Length" field.

   o  Port: May be used to carry a port number.

4.3.  Theory of Operation

   Plain mode operation is as follows:

   (1)  The CPE is provisioned with the reachability information of one
        or several Concentrators (e.g., [I-D.boucadair-mptcp-dhc]).

   (2)  Outgoing TCP packets that can be forwarded by a CPE along MPTCP
        subflows are transformed into TCP packets carried over a MPTCP
        connection.  The decision-making process to decide whether a
        flow should be MPTCP-tagged or not is local to the Concentrator
        and the CPE.  It depends on the policies provisioned by the
        network provider.  As such, the decision-making process is
        policy-driven, implementation- and deployment-specific.

   (3)  MPTCP packets are sent using a plain transport mode (i.e.,
        without any encapsulation header).

        The source IP address and source port number are those assigned
        locally by the CPE.  Because multiple IP addresses may be
        available to the CPE, the address used to rewrite the source IP
        address for an outgoing packet forwarded through a given network
        attachment (typically, a WAN interface) MUST be associated with
        that network attachment.  It is assumed that ingress filtering
        ([RFC2827]) is implemented at the boundaries of the networks to
        prevent any spoofing attack.

        The destination IP address is replaced by the CPE with one of
        the IP addresses of the Concentrator.

        The destination port number may be maintained as initially set
        by the host or altered by the CPE.

        The original destination IP address is copied into a dedicated
        MPTCP option called Plain Mode MPTCP option (see Section 4.2).
        Because of the limited TCP option space, it is RECOMMENDED to
        implement the solution specified in [I-D.ietf-tcpm-tcp-edo].  As
        a reminder, [I-D.touch-tcpm-tcp-syn-ext-opt] specifies a
        proposal for TCP SYN extended option space.

        A binding entry must be maintained by the CPE for that outgoing
        packet.  This binding entry is instantiated by the NAT and/or
        the firewall functions embedded in the CPE.



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   (4)  Upon receipt of the packet on the MPTCP leg, the Concentrator
        extracts the IP address included in the Plain Mode MPTCP Option
        that it uses as the destination IP address of the packet
        generated in the TCP leg towards its ultimate destination.

        The source IP address and port are those of the Concentrators.
        A binding entry is instantiated by the Concentrator to record
        the state.

        The concentrator may be configured to behave as either a 1:1
        address translator or a N:1 translator where the same address is
        shared among multiple CPEs.  Network Providers should be aware
        of the complications that may arise if a given IP address/prefix
        is shared among multiple hosts (see [RFC6967]).  Whether these
        complications apply or not is deployment-specific.

        The Concentrator should preserve the same IP address that was
        assigned to a given CPE for all its outgoing connections when
        transforming an MPTCP connection into a TCP connection.

   (5)  For incoming TCP packets that need to be forwarded to a CPE, the
        Concentrator records the source IP address in a Plain Mode MPTCP
        Option.

        The source IP address is replaced with one of the IP addresses
        listed in the aforementioned binding information base maintained
        by the Concentrator (if such a state entry exists) or with one
        of the Concentrator's IP addresses.

        The destination IP address is replaced with the CPE's IP address
        (if the corresponding state entry is found in the Concentrator's
        binding table) or with one of the CPE's IP addresses (that are
        known by the concentrator using some means that are out of the
        scope of the document).

4.4.  Flow Example

   A typical flow exchange is shown in Figure 3.

   This example assumes no NAT is located between the CPE and the
   concentrator.

   Because the remote server is not MPTCP-aware, the Concentrator is
   responsible for preserving the same IP address (conc_@, in the
   example) for the same CPE even if distinct IP addresses (cpe_@1 and
   cpe_@2, in the example) are used by the CPE to establish subflows
   with the Concentrator.




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                                    +-------+
                                    |DNS    |
        +--------+                  |System |         +------------+
        |  CPE   |                  +-------+         |Concentrator|
        +--------+                      |             +------------+
             |                          |                   |
      DNS    |                          |                   |
    -------->|           DNS Query      |                   |
     Query   |------------------------->|                   |
             |   DNS Reply              |                   |
             |<-------------------------|                   |
             |                                              |
             |                                              |
      src=s_@|src=cpe_@1                         dst=conc_@1|src=conc_@
    -------->|--------Plain Mode MPTCP Option(d_@)--------->|-------->
      dst=d_@|                                              |dst=d_@
                                      ....

             |                                              |
      src=d_@|dst=cpe_@1                         src=conc_@1|src=d_@
    <--------|<-------Plain Mode MPTCP Option(d_@)----------|<-------
      dst=s_@|                                              |dst=conc_@
                                      ....

      src=s_@|src=cpe_@2                         dst=conc_@1|src=conc_@
    -------->|--------Plain Mode MPTCP Option(d_@)--------->|-------->
      dst=d_@|                                              |dst=d_@
                                      ....

    Legend:
      * "--Plain Mode MPTCP Option()->" indicates the packet is sent
        in a plain mode, i.e., without any encapsulation hander,
        and that "Plain Mode MPTCP Option" is carried in the packet.


   Figure 3: Flow Example (No NAT between the CPE and the Concentrator)

5.  UDP Traffic

   From an application standpoint, there may be a value to distribute
   UDP datagrams among available network attachments for the sake of
   network resource optimisation, for example.

   Unlike existing proposals that rely upon encapsulation schemes such
   as IP-in-IP or GRE, this document suggests the use of MPTCP features
   to control how UDP datagrams are distributed among existing network
   attachments.  UDP datagrams are therefore transformed into TCP-
   formatted packets.



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   The CPE and the Concentrator establish a set of MPTCP subflows.
   These subflows are used to transport UDP datagrams that are
   distributed among existent subflows.  TCP session tracking may not be
   enabled for the set of subflows that are dedicated to transport UDP
   traffic.  The establishment of these subflows is not conditioned by
   the receipt of UDP packets; instead, these subflows are initiated
   upon CPE reboot or when network conditions change (e.g., whenever a
   new Concentrator is discovered or a new IP address is assigned to the
   Concentrator).  Additional MPTCP connections may be established to
   anticipate UDP traffic to be distributed among several paths.  The
   maximum number of MPTCP connections that can be dedicated to UDP
   traffic may be configured locally to the CPE and the Concentrator.
   How this parameter is configured is implementation and deployment-
   specific.

   When the CPE (or the Concentrator) transforms a UDP packet into a TCP
   one, it must insert the Plain Mode MPTCP Option with the U-bit set.
   When setting the source IP address, the destination IP address, and
   the IP address enclosed in the Plain Mode MPTCP Option, the same
   considerations specified in Section 4.3 must be followed.

   In addition, the CPE (or the Concentrator) must replace the UDP
   header with a TCP header.  Upon receipt of the packet with the U-bit
   set, the Concentrator (or the CPE) transforms the packet into a UDP
   packet and follows the same considerations specified in Section 4.3.
   Both the CPE and the Concentrator may be configured to disable some
   features (e.g., reordering).  Enabling these features is deployment
   and implementation-specific.

   Relaying UDP packets is not conditioned by TCP session establishment
   because the required subflows that are dedicated to transport UDP
   traffic are already in place (either at the CPE or the Concentrator).

   A flow example is shown in Figure 4.

















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        +--------+                                    +------------+
        |  CPE   |                                    |Concentrator|
        +--------+                                    +------------+
             | /------------------------------------------\ |
             ||    Dedicated MPTCP SubFlows for UDP        ||
             | \------------------------------------------/ |
             |                                              |
      src=s_@|src=cpe_@1                         dst=conc_@1|src=conc_@
    ---UDP-->|---------------------TCP--------------------->|---UDP-->
      dst=d_@|        Plain Mode MPTCP Option(U,d_@)        |dst=d_@
                                      ....
      src=s_@|src=cpe_@2                         dst=conc_@2|src=conc_@
    ---UDP-->|---------------------TCP--------------------->|---UDP-->
      dst=d_@|        Plain Mode MPTCP Option(U,d_@)        |dst=d_@
             |                                              |
                                      ....
      src=s_@|src=cpe_@1                         dst=conc_@1|src=conc_@
    ---UDP-->|---------------------TCP--------------------->|---UDP-->
     dst=d1_@|        Plain Mode MPTCP Option(U,d_@)        |dst=d1_@
             |                                              |
      src=s_@|src=cpe_@1                         dst=conc_@2|src=conc_@
    ---UDP-->|---------------------TCP--------------------->|---UDP-->
     dst=d1_@|        Plain Mode MPTCP Option(U,d_@)        |dst=d1_@
             |                                              |

          Figure 4: Distributing UDP packets over multiple paths

6.  IANA Considerations

   This document requests an MPTCP subtype code for this option:

   o  Plain Mode MPTCP Option

7.  Security Considerations

   The concentrator may have access to privacy-related information
   (e.g., IMSI, link identifier, subscriber credentials, etc.).  The
   concentrator must not leak such sensitive information outside a local
   domain.

   Means to protect the MPTCP concentrator against Denial-of-Service
   (DoS) attacks must be enabled.  Such means include the enforcement of
   ingress filtering policies at the boundaries of the network.  In
   order to prevent exhausting the resources of the concentrator by
   creating an aggressive number of simultaneous subflows for each MPTCP
   connection, the administrator should limit the number of allowed
   subflows per host for a given connection.




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   Attacks outside the domain can be prevented if ingress filtering is
   enforced.  Nevertheless, attacks from within the network between a
   host and a concentrator instance are yet another actual threat.
   Means to ensure that illegitimate nodes cannot connect to a network
   should be implemented.

   Traffic theft is also a risk if an illegitimate concentrator is
   inserted in the path.  Indeed, inserting an illegitimate concentrator
   in the forwarding path allows to intercept traffic and can therefore
   provide access to sensitive data issued by or destined to a host.  To
   mitigate this threat, secure means to discover a concentrator (for
   non-transparent modes) should be enabled.

8.  Acknowledgements

   Many thanks to Chi Dung Phung, Mingui Zhang, and Christoph Paasch for
   the comments.

9.  References

9.1.  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>.

   [RFC6824]  Ford, A., Raiciu, C., Handley, M., and O. Bonaventure,
              "TCP Extensions for Multipath Operation with Multiple
              Addresses", RFC 6824, DOI 10.17487/RFC6824, January 2013,
              <http://www.rfc-editor.org/info/rfc6824>.

9.2.  Informative References

   [I-D.boucadair-mptcp-dhc]
              Boucadair, M., Jacquenet, C., and T. Reddy, "DHCP Options
              for Network-Assisted Multipath TCP (MPTCP)", draft-
              boucadair-mptcp-dhc-04 (work in progress), November 2015.

   [I-D.deng-mptcp-proxy]
              Lingli, D., Liu, D., Sun, T., Boucadair, M., and G.
              Cauchie, "Use-cases and Requirements for MPTCP Proxy in
              ISP Networks", draft-deng-mptcp-proxy-01 (work in
              progress), October 2014.







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   [I-D.ietf-tcpm-tcp-edo]
              Touch, J. and W. Eddy, "TCP Extended Data Offset Option",
              draft-ietf-tcpm-tcp-edo-04 (work in progress), November
              2015.

   [I-D.touch-tcpm-tcp-syn-ext-opt]
              Touch, J. and T. Faber, "TCP SYN Extended Option Space
              Using an Out-of-Band Segment", draft-touch-tcpm-tcp-syn-
              ext-opt-03 (work in progress), October 2015.

   [RFC1701]  Hanks, S., Li, T., Farinacci, D., and P. Traina, "Generic
              Routing Encapsulation (GRE)", RFC 1701,
              DOI 10.17487/RFC1701, October 1994,
              <http://www.rfc-editor.org/info/rfc1701>.

   [RFC1928]  Leech, M., Ganis, M., Lee, Y., Kuris, R., Koblas, D., and
              L. Jones, "SOCKS Protocol Version 5", RFC 1928,
              DOI 10.17487/RFC1928, March 1996,
              <http://www.rfc-editor.org/info/rfc1928>.

   [RFC2473]  Conta, A. and S. Deering, "Generic Packet Tunneling in
              IPv6 Specification", RFC 2473, DOI 10.17487/RFC2473,
              December 1998, <http://www.rfc-editor.org/info/rfc2473>.

   [RFC2827]  Ferguson, P. and D. Senie, "Network Ingress Filtering:
              Defeating Denial of Service Attacks which employ IP Source
              Address Spoofing", BCP 38, RFC 2827, DOI 10.17487/RFC2827,
              May 2000, <http://www.rfc-editor.org/info/rfc2827>.

   [RFC4908]  Nagami, K., Uda, S., Ogashiwa, N., Esaki, H., Wakikawa,
              R., and H. Ohnishi, "Multi-homing for small scale fixed
              network Using Mobile IP and NEMO", RFC 4908,
              DOI 10.17487/RFC4908, June 2007,
              <http://www.rfc-editor.org/info/rfc4908>.

   [RFC6967]  Boucadair, M., Touch, J., Levis, P., and R. Penno,
              "Analysis of Potential Solutions for Revealing a Host
              Identifier (HOST_ID) in Shared Address Deployments",
              RFC 6967, DOI 10.17487/RFC6967, June 2013,
              <http://www.rfc-editor.org/info/rfc6967>.

Authors' Addresses









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Internet-Draft         Plain MPTCP Transport Mode          December 2015


   Mohamed Boucadair
   France Telecom
   Rennes  35000
   France

   Email: mohamed.boucadair@orange.com


   Christian Jacquenet
   France Telecom
   Rennes
   France

   Email: christian.jacquenet@orange.com


   Denis Behaghel
   OneAccess

   Email: Denis.Behaghel@oneaccess-net.com


   Stefano Secci
   Universite Pierre et Marie Curie (UPMC)
   Paris
   France

   Email: stefano.secci@lip6.fr


   Wim Henderickx
   Alcatel-Lucent
   Belgium

   Email: wim.henderickx@alcatel-lucent.com


   Robert Skog
   Ericsson

   Email: robert.skog@ericsson.com










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