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Keyed IPv6 Tunnel
draft-ietf-l2tpext-keyed-ipv6-tunnel-06

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 8159.
Authors Maciek Konstantynowicz , Giles Heron , Rainer Schatzmayr , Wim Henderickx
Last updated 2016-08-23 (Latest revision 2016-03-21)
Replaces draft-mkonstan-l2tpext-keyed-ipv6-tunnel
RFC stream Internet Engineering Task Force (IETF)
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Stream WG state WG Document
Revised I-D Needed - Issue raised by AD
Document shepherd Carlos Pignataro
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Responsible AD Deborah Brungard
Send notices to draft-ietf-l2tpext-keyed-ipv6-tunnel.all@ietf.org
draft-ietf-l2tpext-keyed-ipv6-tunnel-06
L2TPEXT Working Group                            M. Konstantynowicz, Ed.
Internet-Draft                                             G. Heron, Ed.
Intended status: Standards Track                           Cisco Systems
Expires: September 22, 2016                                R. Schatzmayr
                                                     Deutsche Telekom AG
                                                           W. Henderickx
                                                    Alcatel-Lucent, Inc.
                                                          March 21, 2016

                           Keyed IPv6 Tunnel
                draft-ietf-l2tpext-keyed-ipv6-tunnel-06

Abstract

   This document describes a simple L2 Ethernet over IPv6 tunnel
   encapsulation with mandatory 64-bit cookie for connecting L2 Ethernet
   attachment circuits identified by IPv6 addresses.  The encapsulation
   is based on L2TPv3 over IP.

Requirements Language

   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 [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
   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 September 22, 2016.

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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
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Static 1:1 Mapping Without a Control Plane  . . . . . . . . .   3
   3.  64-bit Cookie . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  Encapsulation . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Fragmentation and Reassembly  . . . . . . . . . . . . . . . .   7
   6.  OAM Considerations  . . . . . . . . . . . . . . . . . . . . .   7
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   9.  Contributing Authors  . . . . . . . . . . . . . . . . . . . .   9
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   9
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     11.1.  Normative References . . . . . . . . . . . . . . . . . .   9
     11.2.  Informative References . . . . . . . . . . . . . . . . .  10
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   L2TPv3, as defined in [RFC3931], provides a dynamic mechanism for
   tunneling Layer 2 (L2) "circuits" across a packet-oriented data
   network (e.g., over IP), with multiple attachment circuits
   multiplexed over a single pair of IP address endpoints (i.e. a
   tunnel) using the L2TPv3 session ID as a circuit discriminator.

   Implementing L2TPv3 over IPv6 [RFC2460] provides the opportunity to
   utilize unique IPv6 addresses to identify Ethernet attachment
   circuits directly, leveraging the key property that IPv6 offers, a
   vast number of unique IP addresses.  In this case, processing of the
   L2TPv3 Session ID may be bypassed upon receipt as each tunnel has one
   and only one associated session.  This local optimization does not
   hinder the ability to continue supporting the multiplexing of

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   circuits via the Session ID on the same router for other L2TPv3
   tunnels.

2.  Static 1:1 Mapping Without a Control Plane

   Local configuration creates a one-to-one mapping between the access-
   side L2 attachment circuit and the IP address used in the network-
   side IPv6 encapsulation.  The L2TPv3 Control Plane defined in RFC3931
   is not used - but rather the management plane is used to create, and
   to maintain, matching configurations at either end of each tunnel.

   The IPv6 L2TPv3 tunnel encapsulating device uniquely identifies each
   Ethernet L2 attachment connection by a port ID or a combination of
   port ID and VLAN ID(s) on the access side, and by a local IPv6
   address on the network side.  The local IPv6 address also identifies
   the tunnel endpoint.  The local IPv6 addresses identifying L2TPv3
   tunnels SHOULD NOT be assigned from connected IPv6 subnets facing
   towards remote tunnel endponts - since that approach would result in
   an IPv6 Neighbor Discovery cache entry per tunnel on the next hop
   router towards the remote tunnel endpoint.  It is RECOMMENDED that
   local IPv6 addresses identifying L2TPv3 tunnels are assigned from
   dedicated subnets used only for such tunnel endpoints.

   Certain deployment scenarios may require using a single IPv6 address
   (typically a globally routable unicast or anycast address assigned to
   a virtual interface) to identify a tunnel endpoint for multiple IPv6
   L2TPv3 tunnels.  For such cases the tunnel encapsulating device
   identifies each tunnel by a unique combination of local and remote
   IPv6 addresses.

   As mentioned above Session ID processing is not required as each
   keyed IPv6 tunnel has one and only one associated session.  However
   for compatibility with existing RFC3931 implementations, the packets
   need to be sent with Session ID.  Routers implementing L2TPv3
   according to RFC3931 can be configured with multiple L2TPv3 tunnels,
   with one session per tunnel, to interoperate with routers
   implementing the keyed IPv6 tunnel as specified by this document.
   Note that as Session ID processing is not enabled for keyed IPv6
   tunnels that there can only be a single keyed IPv6 tunnel between two
   IPv6 addresses.

   Note that a previous IETF draft [I.D.ietf-pppext-l2tphc] introduced
   the concept of an L2TP tunnel carrying a single session and hence not
   requiring session ID processing.

   There are various advantages to this approach when compared to the
   "traditional" L2TPv3 approach of using a loopback address to
   terminate the tunnel and then carrying multiple sessions over the

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   tunnel.  These include better ECMP load-balancing (since each tunnel
   has a unique source/destination IPv6 address pair), and finer-grained
   control when advertising tunnel endpoints using a routing protocol.

3.  64-bit Cookie

   In line with RFC3931, the 64-bit cookie is used for an additional
   tunnel endpoint context check.  This is the largest cookie size
   permitted in RFC3931.  All packets MUST carry the 64-bit L2TPv3
   cookie field.  The cookie MUST be 64 bits long in order to provide
   sufficient protection against spoofing and brute force blind
   insertion attacks.  The cookie values SHOULD be randomly selected.

   In the absence of the L2TPv3 Control Plane, the L2TPv3 encapsulating
   router MUST be provided with local configuration of the 64-bit cookie
   for each local and remote IPv6 endpoint.  Note that cookies are
   asymmetric, so local and remote endpoints may send different cookie
   values, and in fact SHOULD do so.  The value of the cookie MUST be
   able to be changed at any time in a manner that does not drop any
   legitimate tunneled packets - i.e. the receiver MUST be configurable
   to accept two discrete cookies for a single tunnel simultaneously.
   This enables the receiver to hold both the 'old' and 'new' cookie
   values during a change of cookie value.  Cookie values SHOULD be
   changed periodically by the management plane.

   Note that mandating a 64-bit cookie is a change from the optional
   variable-length cookie of RFC3931, and that this requirement
   constrains interoperability with existing RFC3931 implementations to
   those supporting a 64-bit cookie.

4.  Encapsulation

   The ingress router encapsulates the entire Ethernet frame, without
   the preamble and frame check sequence (FCS) in L2TPv3 as per RFC4719
   [RFC4719].  The L2-specific sublayer MAY be carried if VCCV and/or
   frame sequencing is required, but SHOULD NOT be carried otherwise.
   The L2TPv3 packet is encapsulated directly over IPv6 (i.e. no UDP
   header is carried).

   The ingress router MAY retain the FCS as per section 4.7 of
   [RFC4720].  Support for retaining the FCS and for receiving packets
   with a retained FCS is OPTIONAL, and if present MUST be configurable.
   In the absence of the L2TPv3 control plane such configuration MUST be
   consistent for the two endpoints of any given tunnel - i.e. if one
   router is configured to retain the FCS then the other router MUST be
   configured to receive packets with the retained FCS.  Any router
   configured to retain FCS for a tunnel MUST retain FCS for all frames
   sent over that tunnel.  All routers implementing this specification

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   MUST support the ability to send frames without retaining the FCS and
   to receive such frames.

   Any service-delimiting IEEE 802.1Q [IEEE802.1Q] or IEEE 802.1ad
   [IEEE802.1ad] VLAN IDs - S-tag, C-tag or tuple (S-tag, C-tag) - are
   treated with local significance within the Ethernet L2 port and MUST
   NOT be forwarded over the IPv6 L2TPv3 tunnel.

   Note that the same approach may be used to transport protocols other
   than Ethernet.

   The full encapsulation is as follows:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      +                   IPv6 Header (320 bits)                      +
      ~                                                               ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                    Session ID (32 bits)                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Cookie (0:31)                          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Cookie (32:63)                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          (Optional) L2-specific Sublayer (32 bits)            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Payload (variable)                       |
      |                              ?                                |
      |                              ?                                |
      |                              ?                                |
      |                              ?                                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The combined IPv6 and Keyed IP Tunnel header contains the following
   fields:

   o  IPv6 Header.  Note that:

      *  The traffic class may be set by the ingress router to ensure
         correct PHB treatment by transit routers between the ingress
         and egress, and correct QoS disposition at the egress router.

      *  The flow label, as defined in [RFC6437] may be set by the
         ingress router to indicate a flow of packets from the client

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         which may not be reordered by the network (if there is a
         requirement for finer grained ECMP load balancing than per-
         circuit load balancing).

      *  The next header will be set to 0x73 to indicate that the next
         header is L2TPv3.

      *  In the "Static 1:1" case the IPv6 source address may correspond
         to a port or port/VLAN being transported as an L2 circuit, or
         may correspond to a virtual interface terminating inside the
         router (e.g. if L2 circuits are being used within a multipoint
         VPN, or if an anycast address is being terminated on a set of
         data center virtual machines.)

      *  As with the source address the IPv6 destination address may
         correspond to a port or port/VLAN being transported as an L2
         circuit, or to a virtual interface.

   o  Session ID.  In the "Static 1:1 mapping" case described in
      Section 2, the IPv6 address identifies an L2TPv3 session directly,
      thus at endpoints supporting one-stage resolution (IPv6 Address
      only) the Session ID SHOULD be ignored upon receipt.  It is
      RECOMMENDED that the remote endpoint is configured to set the
      Session ID to all ones (0xFFFFFFFF) for easy identification in
      case of troubleshooting.  For compatibility with other tunnel
      termination platforms supporting only two-stage resolution (IPv6
      Address + Session ID), this specification recommends supporting
      explicit configuration of Session ID to any value other than zero
      (including all ones).  The Session ID of zero MUST NOT be used, as
      it is reserved for use by L2TP control messages as specified in
      RFC3931.  Note that the Session ID is unidirectional - the sent
      and received Session IDs at an endpoint may be different.

   o  Cookie.  64-bit cookie, configured and described as in Section 3.
      All packets for a destined L2 circuit (or L2TPv3 Session) MUST
      match one of the cookie values configured for that circuit.  Any
      packets that do not contain a valid cookie value MUST be discarded
      (see RFC3931 for more details).

   o  L2-specific sublayer (optional).  As noted above this will be
      present if VCCV and/or frame sequencing is required.  If VCCV is
      required then any frames with bit 0 (the "V-bit") set are VCCV
      messages.  If frame sequencing is required then any frames with
      bit 1 (the "S-bit") set have a valid frame sequence number in bits
      8 - 31.

   o  Payload (variable length).  As noted above the preamble and any
      service-delimiting tags MUST be stripped before encapsulation and

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      the FCS MUST be stripped unless FCS retention is configured at
      both ingress and egress routers.  Since a new FCS is added at each
      hop when the encapsulating IP packet is transmitted the payload is
      protected against bit errors.

5.  Fragmentation and Reassembly

   Using tunnel encapsulation, Ethernet L2 datagrams in IPv6 in this
   case, will reduce the effective MTU of the encapsulated traffic.

   The recommended solution to deal with this problem is for the network
   operator to increase the MTU size of all the links between the
   devices acting as IPv6 L2TPv3 tunnel endpoints to accommodate both
   the IPv6 L2TPv3 encapsulation header and the Ethernet L2 datagram
   without fragmenting the IPv6 packet.

   It is RECOMMENDED that routers implementing this specification
   implement IPv6 PMTU discovery as defined in [RFC1981] to confirm that
   the path over which packets are sent has sufficient MTU to transport
   a maximum length Ethernet frame plus encapsulation overhead.

   Routers implementing this specification MAY implement L2TPv3
   fragmentation (as defined in section 5 of [RFC4623]).  In the absence
   of the L2TPv3 control plane, it is RECOMMENDED that fragmentation (if
   implemented) is locally configured on a per-tunnel basis.
   Fragmention configuration MUST be consistent between the two ends of
   a tunnel.

   It is NOT RECOMMENDED for routers implementing this specification to
   enable IPv6 fragmentation (as defined in section 4.5 of RFC2460) for
   keyed IP tunnels.  IP fragmentation issues for L2TPv3 are discussed
   in section 4.1.4 of RFC3931.

6.  OAM Considerations

   OAM is an important consideration when providing circuit-oriented
   services such as those described in this document, and all the more
   so in the absence of a dedicated tunnel control plane, as OAM becomes
   the only way to detect failures in the tunnel overlay.

   Note that in the context of keyed IP tunnels, failures in the IPv6
   underlay network can be detected using the usual methods such as
   through the routing protocol, potentially including the use of
   single-hop Bidirectional Forwarding Detection ( BFD ) [RFC5881] to
   rapidly detect link failures.  Multi-Hop BFD MAY also be enabled
   between tunnel endpoints as per [RFC5883].

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   Since keyed IP tunnels always carry an Ethernet payload, and since
   OAM at the tunnel layer is unable to detect failures in the Ethernet
   service processing at the ingress or egress router, or on the
   Ethernet attachment circuit between the router and the Ethernet
   client, it is RECOMMENDED that Ethernet OAM as defined in
   [IEEE802.1ag] and/or [Y.1731] is enabled for keyed IP tunnels.  More
   specifically the following Connectivity Fault Management ( CFM ) and/
   or Ethernet continuity check ( ETH-CC ) configurations are to be used
   in conjunction with keyed IPv6 tunnels:

   o  Connectivity verification between the tunnel endpoints across the
      tunnel - use an Up MEP located at the tunnel endpoint for
      transmitting the CFM PDUs towards, and receiving them from the
      direction of the tunnel.

   o  Connectivity verification from the tunnel endpoint across the
      local attachment circuit - use a Down MEP located at the tunnel
      endpoint for transmitting the CFM PDUs towards, and receiving them
      from the direction of the local attachment circuit.

   o  Intermediate connectivity verification - use a MIP located at the
      tunnel endpoint to generate CFM PDUs in response to received CFM
      PDUs.

   In addition Pseudowire Virtual Circuit Connectivity Verification (
   VCCV ) [RFC5085] MAY be used.  Furthermore BFD MAY be enabled over
   the VCCV channel [RFC5885].

7.  IANA Considerations

   None.

8.  Security Considerations

   Packet spoofing for any type of Virtual Private Network (VPN)
   tunneling protocol is of particular concern as insertion of carefully
   constructed rogue packets into the VPN transit network could result
   in a violation of VPN traffic separation, leaking data into a
   customer VPN.  This is complicated by the fact that it may be
   particularly difficult for the operator of the VPN to even be aware
   that it has become a point of transit into or between customer VPNs.

   Keyed IPv6 encapsulation provides traffic separation for its VPNs via
   use of separate 128-bit IPv6 addresses to identify the endpoints.
   The mandatory use of the 64 bit L2TPv3 cookie provides an additional
   check to ensure that an arriving packet is intended for the
   identified tunnel.

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   In the presence of a blind packet spoofing attack, the 64-bit L2TPv3
   cookie provides security against inadvertent leaking of frames into a
   customer VPN, as documented in section 8.2 of RFC3931.

   For protection against brute-force, blind, insertion attacks, the 64-
   bit cookie MUST be used with all tunnels.

   Note that the cookie provides no protection against a sophisticated
   man-in-the-middle attacker who can sniff and correlate captured data
   between nodes for use in a coordinated attack.

   The L2TPv3 64-bit cookie must not be regarded as a substitute for
   security such as that provided by IPsec when operating over an open
   or untrusted network where packets may be sniffed, decoded, and
   correlated for use in a coordinated attack.

9.  Contributing Authors

   Peter Weinberger
   Cisco Systems

   Email: peweinbe@cisco.com

   Michael Lipman
   Cisco Systems

   Email: mlipman@cisco.com

   Mark Townsley
   Cisco Systems

   Email: townsley@cisco.com

10.  Acknowledgements

   The authors would like to thank Carlos Pignataro, Stewart Bryant,
   Karsten Thomann, Qi Sun and Ian Farrer for their insightful
   suggestions and review.

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>.

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   [RFC2460]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", RFC 2460, DOI 10.17487/RFC2460,
              December 1998, <http://www.rfc-editor.org/info/rfc2460>.

   [RFC3931]  Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed.,
              "Layer Two Tunneling Protocol - Version 3 (L2TPv3)",
              RFC 3931, DOI 10.17487/RFC3931, March 2005,
              <http://www.rfc-editor.org/info/rfc3931>.

   [RFC4719]  Aggarwal, R., Ed., Townsley, M., Ed., and M. Dos Santos,
              Ed., "Transport of Ethernet Frames over Layer 2 Tunneling
              Protocol Version 3 (L2TPv3)", RFC 4719,
              DOI 10.17487/RFC4719, November 2006,
              <http://www.rfc-editor.org/info/rfc4719>.

11.2.  Informative References

   [I.D.ietf-pppext-l2tphc]
              Valencia, A., "L2TP Header Compression", December 1997.

   [IEEE802.1ad]
              IEEE, "802.1ad-2005 - IEEE Standard for Local and
              Metropolitan Area Networks - Virtual Bridged Local Area
              Networks - Amendment 4: Provider Bridges", 2005.

   [IEEE802.1ag]
              IEEE, "IEEE Standard for Local and metropolitan area
              networks - Virtual Bridged Local Area Networks, Amendment
              5: Connectivity Fault Managements", 2007.

   [IEEE802.1Q]
              IEEE, "802.1Q-2014 - IEEE Standard for Local and
              metropolitan area networks - Bridges and Bridged
              Networks", 2014.

   [RFC1981]  McCann, J., Deering, S., and J. Mogul, "Path MTU Discovery
              for IP version 6", RFC 1981, DOI 10.17487/RFC1981, August
              1996, <http://www.rfc-editor.org/info/rfc1981>.

   [RFC4623]  Malis, A. and M. Townsley, "Pseudowire Emulation Edge-to-
              Edge (PWE3) Fragmentation and Reassembly", RFC 4623,
              DOI 10.17487/RFC4623, August 2006,
              <http://www.rfc-editor.org/info/rfc4623>.

   [RFC4720]  Malis, A., Allan, D., and N. Del Regno, "Pseudowire
              Emulation Edge-to-Edge (PWE3) Frame Check Sequence
              Retention", RFC 4720, DOI 10.17487/RFC4720, November 2006,
              <http://www.rfc-editor.org/info/rfc4720>.

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   [RFC5085]  Nadeau, T., Ed. and C. Pignataro, Ed., "Pseudowire Virtual
              Circuit Connectivity Verification (VCCV): A Control
              Channel for Pseudowires", RFC 5085, DOI 10.17487/RFC5085,
              December 2007, <http://www.rfc-editor.org/info/rfc5085>.

   [RFC5881]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
              DOI 10.17487/RFC5881, June 2010,
              <http://www.rfc-editor.org/info/rfc5881>.

   [RFC5883]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD) for Multihop Paths", RFC 5883, DOI 10.17487/RFC5883,
              June 2010, <http://www.rfc-editor.org/info/rfc5883>.

   [RFC5885]  Nadeau, T., Ed. and C. Pignataro, Ed., "Bidirectional
              Forwarding Detection (BFD) for the Pseudowire Virtual
              Circuit Connectivity Verification (VCCV)", RFC 5885,
              DOI 10.17487/RFC5885, June 2010,
              <http://www.rfc-editor.org/info/rfc5885>.

   [RFC6437]  Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
              "IPv6 Flow Label Specification", RFC 6437,
              DOI 10.17487/RFC6437, November 2011,
              <http://www.rfc-editor.org/info/rfc6437>.

   [Y.1731]   ITU, "ITU-T Recommendation G.8013/Y.1731 - OAM functions
              and mechanisms for Ethernet based networks", 2011.

Authors' Addresses

   Maciek Konstantynowicz (editor)
   Cisco Systems

   Email: maciek@cisco.com

   Giles Heron (editor)
   Cisco Systems

   Email: giheron@cisco.com

   Rainer Schatzmayr
   Deutsche Telekom AG

   Email: rainer.schatzmayr@telekom.de

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   Wim Henderickx
   Alcatel-Lucent, Inc.

   Email: wim.henderickx@alcatel-lucent.com

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