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Versions: 00 01 02                                                      
GSMP Working Group Internet Draft                    Jun Kyun Choi(ICU)
Document: draft-ietf-gsmp-optical-spec-00.txt         Min Ho Kang(ICU)
Expiration Date: April 2003                          Jung Yul Choi(ICU)
                                                    Gyu Myoung Lee(ICU)
                                                          Joo Uk Um(KT)
                                                           October 2002


    General Switch Management Protocol (GSMP) v3 for Optical Support


Status of this Memo

  This document is an Internet-Draft and is in full conformance with
  all provisions of Section 10 of RFC-2026.

  Internet-Drafts are working documents of the Internet Engineering
  Task Force (IETF), its areas, and its working groups. Note that other
  groups MAY also distribute working documents as Internet-Drafts.

  Internet-Drafts are draft documents valid for a maximum of six months
  and MAY be updated, replaced, or obsolete 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."

  The list of current Internet-Drafts can be accessed at
  http://www.ietf.org/ietf/1id-abstracts.txt

  The list of Internet-Draft Shadow Directories can be accessed at
  http://www.ietf.org/shadow.html.


Abstract

  This document describes the GSMPv3 for the support of optical switching.
  GSMP controller SHOULD control optical label switches and manage optical
  resources on them. This document describes the extended functions of
  GSMP for optical switching and explains operational mechanisms to
  implement them. It SHOULD be referred with [1] for the complete
  implementation.


Conventions

  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.


Table of Contents


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              GSMPv3 for Optical Support                  October 2002

  1. Introduction.....................................................3
  2. Common Definition and Procedures for Optical Support.............3
  2.1 Labels..........................................................3
  2.1.1 Label for Wavelength and Fiber................................3
  2.1.2 Label for Waveband............................................4
  2.1.3 Label for optical burst ......................................4
  2.1.4 Label Range...................................................4
  2.2 Protection and Restoration Capability in GSMP...................4
  2.2.1 Dedicated and shared recovery mechanisms......................5
  2.2.2 Revertible and Non-revertible mode............................5
  2.3 GSMP support for optical switching systems......................6
  2.3.1 Capability of GSMP for optical burst switching................6
  3. Connection Management Messages...................................7
  3.1 General Message Definitions.....................................7
  3.2 Add Branch Message..............................................7
  3.3 Move Output Branch Message......................................7
  3.4 Move Input Branch Message.......................................7
  4. Reservation Management Messages..................................7
  5. State and Statistics Messages....................................8
  5.1 Statistics Messages.............................................8
  6. Configuration Messages...........................................8
  6.1 Switch Configuration Message....................................9
  6.2 Port Configuration Message......................................9
  6.3 Service Configuration Message...................................9
  7. Event Messages...................................................9
  8. Failure Response Codes...........................................10
  9. Security Consideratons...........................................10
  References..........................................................10
  Acknowledgement.....................................................11
  Author's Addresses..................................................11
  Full Copyright Statement............................................13



1. Introduction

  This document describes the extended functions and requirements of
  GSMPv3 for the support of optical switching. GSMPv3 is an asymmetric
  protocol to control and manage the label switch. The label switches
  that are used for optical switching are all optical cross-connects
  (optical-optical-optical), transparent optical cross connects
  (optical-electrical-optical, frame independent).

  In order for GSMP to operate between the controller and optical
  switched and cross connects, optical labels, services for optical
  switching, and resource abstractions MUST be defined and added to


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             GSMPv3 for Optical Support                  October 2002

  GSMP, since the basic optical resources which are used in connection
  setup are different with them of the legacy networks.

  One of the main roles of GSMP is to support restoration capabilities
  of optical switches and the connection. By extending the management
  messages of GSMP, this function MUST be implemented.

  For the complete implementation this document MUST be referred with
  [1].


2. Common Definitions and Procedures for Optical Support.

  Common definitions and procedures which are not mentioned in this
  document follow [1].

2.1 Labels

  Labels are the basic identifier for a connection. In order to setup
  connections in optical switch, new labels MUST be defined. The newly
  defined labels identify the entities that are to be switched in the
  optical switches. GMPLS defines packet switching capable, TDM
  switching capable, lambdas switching capable, fiber switching capable
  interfaces, and it introduces the needs of generalized labels to
  support them [3][4]. So far, GMPLS does not defined the labels to be
  used for optical switching (label formats and encoding schemes), but
  GSMP MUST support the all types of label that to be defined in GMPLS.
  The following lists are the labels to be supported in the optical
  switching [2][3][4].

     - a single fiber in a bundle
     - a single waveband within a fiber
     - a single wavelength within a waveband (or a fiber)
     - an optical burst within a wavelength

2.1.1 Labels for Wavelength and Fiber

  The label indicates a fiber or a wavelength to be used for a
  connection establishment in optical switching. Value of the label
  only has significance between two neighbors, and the receiver MAY
  need to convert the received value into a value that has local
  significance.

2.1.2 Labels for Waveband

  A Waveband is a set of contiguous wavelengths which can be switched
  together to a new waveband [3][4]. It MAY be desirable for an optical
  cross connect to optically switch multiple wavelengths as a unit
  since it MAY reduce the distortion on the individual wavelengths and
  MAY allow tighter separation of the individual wavelengths. The
  Waveband Label is defined to support such a waveband switching. The
  waveband label can be encoded in three parts; waveband ID, start
  label, and end label. The start label and the end label represent the


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             GSMPv3 for Optical Support                  October 2002

  lowest value wavelength and the highest value wavelengths.

2.1.3 Labels for optical burst

  The label for optical burst represents the label for switching optical
  burst data in time domain in a wavelength. However, this label is not
  defined yet.

2.1.4 Label Range

  The basic label range to be used in each port is specified by the
  Port Configuration or All Port Configuration message. The Label Range
  message allows the range of labels supported by a specified port to
  be changed. The controller MUST allocate the label range with
  consideration of optical characteristics when assigning the labels
  for a connection because the connection is established per optical
  burst, wavelength, waveband, and fiber in optical domain. Since the
  basic label range varies in switches and the labels for the
  connections can be different due to the optical characteristics, GSMP
  does not treat them. However, the following lists SHOULD be
  considered and the available label ranges can be applied in the Label
  Range message.

     - When allocating a label for a wavelength, the label SHOULD be
     allocated for it with consideration of wavelength continuity. For
     satisfying the requirement of wavelength continuity in a
     connection, the label SHOULD be allocated to maintain the same
     wavelength for it. The controller MUST manage the available labels
     and support the constraint.

     - The labels to be used for waveband switching MUST be contiguous,
     because the waveband switching is possible only in the set of
     contiguous wavelengths. The decision mechanism for the available
     label range is out of scope of GSMPv3.

2.2 Protection and Restoration Capability in GSMP

  The GSMP controller MUST support the protection and restoration
  capabilities because the optical switch delivers several Gbps data
  traffic in a single wavelength. To achieve fast protection and
  restoration, the optical switch is capable of taking an action
  independent of the GSMP controller, then it informs the controller
  after completing the restoration [2]. This differs from the master-
  slave relationship in GSMP. Therefore, the GSMP port configuration
  command MUST be extended to allow autonomous protection mechanism.
  The current GSMP connection management also MUST be extended to
  support this function.

2.2.1 Dedicated and shared recovery mechanisms

  In the dedicated protection, both working and backup path deliver the
  traffic simultaneously from an ingress node to an egress node. The


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             GSMPv3 for Optical Support                  October 2002

  egress node of the path selects one of them as a working path
  according to the received signal status from the previous node. Since
  the backup path also delivers the traffic it MUST be established by
  using the Add Branch message. When any link in the working path fails,
  the egress node switches over from the failed working path to the
  backup path without noticing the GSMP controller automatically.

  After completing the recovery of the failed path, the switch reports
  the fact of configuring a new connection to the controller. When the
  failed original path is repaired the controller determines how to
  deal with the path according to the revertible or nonrevertible mode.
  In the revertible mode, the currently used backup path is changed to
  the repaired original path by using the Move Input Branch message
  which includes the new port and label of which values are used for
  the original connection. In the nonrevertible mode, the controller
  deletes the repaired original working path by using the Delete Branch
  message, or uses it as a new backup path for the currently used
  backup path by using the Add Branch message.

  In 1:N shared protection, N working paths share the one backup path.
  In a different way of the dedicated protection, the shared path does
  not deliver any traffic since the controller does not know which
  working paths will use it. The controller uses the Reservation
  message to reserve a connection for the backup path. When a link
  fails among the N working paths, the controller issues the Add Branch
  message to restore the traffic through the failed working path into
  the new backup path

2.2.2 Revertible and Non-revertible mode

  In the revertible mode, when the failed working path is repaired, the
  controller restores the currently used backup path to the original
  working path. The GSMP controller MUST keep the information for the
  working path. The controller issues the Move Input/Output Branch
  messages with the new port and label of which values are that of the
  working path to restore it. After restoring, the backup path is
  deleted by using the Delete message or continuously used as a backup
  purpose.

  In non-revertible mode, the working path is not restored from the
  currently used backup path even though it is repaired. The original
  working path can be used as a new backup path by using the Add Branch
  message (1+1 dedicated protection), or the Reservation message (1:N
  shared protection)

2.3 GSMP support for optical switching systems

  GSMP SHOULD control and manage the optical cross-connect systems as
  label switches. The optical cross-connect (OXC) is a space division
  switch that can switch an optical data stream on an input port to an
  output port.


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  The OXC system can be consist of switching fabric,
  multiplexer/demultiplexer, wavelength converter, and optical-
  electrical/electrical-optical converter. Multiple wavelengths are
  multiplexed or demultiplexed into a fiber. Multiple fibers belongs to
  a fiber bundle. A wavelength, a waveband, and a fiber can be used to
  establish a connection in an optical switch. They SHOULD be
  recognized at a port in the OXC since they are connection entities.
  When the OXC has optical-electrical conversion at the input port and
  electrical-optical conversion at the output port it is called as
  opaque OXC. Or, when it processes optical data stream all optically
  it is called as transparent OXC. Wavelength converter SHOULD be used
  to resolve output port contention when two different connections try
  to be established in a same output port. Since the wavelength
  converter can work only within a limited operating range, the limited
  numbers of wavelengths are used at the output port. It limits the
  available wavelengths at the output port.

  In order to control and manage the OXC systems, GSMP SHOULD be
  located as a subset of functions for it and MUST know the current
  switch, port and service configuration information. GSMP controller
  SHOULD identify the connection entities at the OXC and match them
  with the optical labels.

2.3.1 Capability of GSMP for optical burst switching

  GSMPv3 SHOULD also support data burst switching as a new connection
  entity in optical domain. As described in [9],[10], connection setup
  for optical burst includes reserving time on the transport medium for
  the client.

  This time is characterized by two parameters: a start time and the
  duration of data burst. These values MAY define a fast one-way
  reservation. Upon a request for setup of a burst connection, the GSMP
  controller MUST perform appropriate Connection Admission Control for
  the time and duration specified. If the connection is allowed, it
  MUST signal these parameters to the burst switching device to reserve
  the exact bandwidth required [9],[10]. The burst switch MUST perform
  the switching operation autonomously, using the synchronization
  methods prescribed for the burst network it is operating in.



3. Connection Management Messages

3.1 General Message Definitions

  Connection management messages, which are used for establishing,
  releasing, modifying, and verifying connections across the switch by
  the controller, can operate in the optical domain, as the same
  mechanisms. However, it is not possible to process each packet in
  optical domain so that such a traffic parameter can not be used to
  specify the connection. Connection management messages also SHOULD
  support the OXC restoration capabilities.


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3.2 Add Branch Message

  The Add Branch message is used to setup a connection. Especially, it
  MUST support restoration capabilities in the optical domain.  For 1+1
  dedicated protection, it is required to make an additional connection
  as a backup path to protect an original connection against failure.
  Additional fields are not required in the Add Branch message to
  support the restoration capabilities since the two connections are
  used for data traffic and an egress node selects one between them so
  that they functions same. However, the controller SHOULD know the
  whole statues of the switch.

3.3 Move Output Branch Message

  The Move Output Branch message is used to change the current output
  port label to the new output port label for re-establishing the
  existing connection. It can be used to support restoration
  capabilities. Since to re-establish output port of a switch at an
  ingress node is to change a start point of the current connection, it
  can be used for 1:1 protection or 1:N shared protection where an
  ingress node begins a connection. Upon a fault occurring, in order to
  setup a new backup path instead of the failed working path, the new
  port in upstream node SHOULD be connected to the current connection
  by using this message. Because, the ingress node also takes
  responsibility for recovery, as well as the egress node.

3.4 Move Input Branch Message

  The Move Input Branch message is used to change the current input
  port label to the new input port label for re-establishing the
  existing connection. It is also used to support restoration
  capabilities. It is used for the revertible mode that is to move back
  to the original connection from a backup connection after a recovery
  completed. The new port/label in this message uses that of the
  original connection.


4. Reservation Management Messages

  The Reservation Management message that reserves resources for a
  connection before establishing a connection SHOULD reserve optical
  resources, such as data burst, wavelengths, a set of wavelengths for
  waveband switching, and fibers. In order to use the reservation
  management messages, optical resources which the OXC supports SHOULD
  be defined. It can be used to support restoration capabilities for
  reserving backup connections. Especially, 1:N shared protection
  scheme reserves a spare connection which is reserved for N working
  connections so that this MUST use the reservation request messages
  for reserving a backup connection. The reserved connection identified
  by the reservation ID SHOULD be informed to N working connections. In
  the reservation request message, the input label and output label of
  the reserving branch SHOULD be assigned. After a fault occurs, the


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  recovery procedure to make a backup connection just follows the
  ordinary connection setup procedure in [1].


5. State and Statistics Messages

  The State and Statistics messages can be used to monitor the
  statistics related to ports and connection for optical transmission.
  It allows the controller to request the state and statistics of the
  switch.

5.1 Statistics Messages

  The statistics messages are used to query the performance statistics
  related to ports and connections for optical transmission. Since the
  current statistics messages in [1] report the statistics related to
  traffic states per cells, or frames, the new fields SHOULD be added
  into the message for querying the optical support. The Port
  Statistics message requests the statistics for the ports of the
  switch. The Connection Statistics message allows the controller to
  report the performances and statistics of the connection itself. The
  statistics elements to monitor in the OXC are following.

     - signal degradation
     - loss of signal

  As a result of performance analysis through the statistics messages,
  the new connection can be requested when the controller finds the
  much degraded performance on the connection. Therefore, the
  statistics message to detect a fault SHOULD be defined, but the fault
  detection mechanism is out of scope of this document.


6. Configuration Messages

  The configuration messages allow the controller to discover the
  capabilities of optical switch. Switch configuration, port
  configuration, and service configuration messages are defined for
  these functions.

6.1 Switch Configuration Message

  Since an optical switch MAY be able to provide connection services at
  multiple transport layers, and not all switches are expected to
  support the same transport layers, the switch will need to notify the
  controller of the specific layers it can support. Therefore, the
  switch configuration message MUST be extended to provide a list of
  the transport layers for which an optical switch can perform
  switching. The following lists are the possible switching layers.


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             GSMPv3 for Optical Support                  October 2002

     - switching per optical burst
     - switching per a single wavelength
     - switching per a waveband
     - switching per a single fiber
     - switching per a fiber bundle

6.2 Port Configuration Message

  The port configuration message supplies the controller with the
  configuration information related to a single port. In the OXC, the
  new port types SHOULD be defined in GSMP. Port types MUST be added to
  support the mix of optical signals that can operate over a single
  fiber. Basically the port can be used per wavelength, per fiber, and
  per fiber bundle. Moreover, the OXC can have many bays which contain
  hundreds of shalves which have tens of thousands of port. Therefore,
  physical bay and shelve identifiers also SHOULD be defined and
  encoded in port configuration message. The port configuration
  information that MAY need to be conveyed includes:

     - available wavelengths per interface
     - bit rate per wavelength (port)
     - type of fiber

6.3 Service Configuration Message

  The Service Configuration message requests the optical switch for the
  configuration information of the supported services. The requested
  services are identified in the service ID in the Add Branch message
  or the Reservation message. The service model is defined with traffic
  parameter, QoS parameter, and traffic control elements in [1], but
  these parameters can not be used to specify the optical services.
  Therefore this message SHOULD be modified to support optical services
  with newly defined capability sets. The services supported at optical
  switches SHOULD be defined for dealing with optical burst, wavelength,
  waveband, and fiber connection.


7. Event Messages

  The Event messages allow the switch to inform the controller of
  certain asynchronous events. The asynchronous events include mainly
  port states indication. The indication of these asynchronous events
  related to ports can provide a port failure to the controller and it
  can initiate a fault recovery mechanism.


8. Failure Response Codes

  This chapter describes the failure and warning states which can occur
  in setup optical connections. The following lists are the codes that
  SHOULD be defined and added in the Failure Response messages. These
  codes MAY be added when the services for optical switching are
  defined. The code numbers will be assigned in IANA.


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             GSMPv3 for Optical Support                  October 2002

     - no available wavelength at a port
     - no available backup link for protection
     - waveband connection setup fails
     - reservation for optical burst fails


9. Security Considerations
  This document does not have any security concerns. The security
  requirements using this document are described in the referenced
  documents


References

  [1] Doria, A, Sundell, K, Hellstrand, F, Worster, T, "General Switch
  Management Protocol V3," RFC 3292, June 2002.

  [2] Georg Kullgren, et. al., "Requirements For Adding Optical Support
  To GSMPv3",draft-ietf-gsmp-reqs-03.txt, Sept. 2002

  [3] Mannie, E., et. al., "Generalized Multi-Protocol Label Switching
  (GMPLS) Architecture," draft-ietf-ccamp-gmpls-architecture-03.txt,
  August 2002.

  [4] Ashwood-Smith, D., et. al., "Generalized MPLS - Signaling
  Functional Description," Internet Draft draft-ietf-mpls-generalized-
  signaling-08.txt, April 2002.

  [5] Rajagopalan, B., et. al., _IP over Optical Networks: A Framework,
  draft-ietf-ipo-framework-02.txt (work in progress), June 2002.

  [6] N. Chandhok, et. al., "IP over WDM Networks; A Summary Issue",
  draft-osu-ipo-mpls-issues-00,txt, July 2000

  [7] Jin Ho Hahm, Kwang-il Lee, Mark Carson, "Control Mechanisms for
  Traffic Engineering in Optical Networks", drafh-hahm-te-optical-
  00.txt, July 2000

  [8] Daniel Awduche, WYakov Rekhter, "Multiprotocol Lambda Switching:
  Combining MPLS Traffic Engineering Control with Optical
  Crossconnects", IEEE Comm. Mag., March 2001

  [9] C. Qiao, M. Yoo, "Choice, and Feature and Issues in Optical Burst
  Switching", Optical Net. Mag., vol.1, No.2, Apr.2000, pp.36-44.

  [10] OBS Ilia Baldine, George N. Rouskas, Harry G. Perros, Dan
  Stevension, "JumpStart: A Just-in-time Signaling Architecture for WDM
  Burst-Switching Networks", IEEE Comm. Mag., Fab. 2002.

  [11] Angela Chiu, John Strans, et. al., "Impairments And Other
  Constraints On Optical Layer Routing", draft-ietf-ipo-impairments-
  02.txt, Feb. 2002.

  [12] Luc Ceuppens, et. al., "Performance Monitoring in Photonic
  Networks in support of MPL(ambda)S", draft-ceuppens-mpls-optical-
  00.txt, Jung 2000.


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              GSMPv3 for Optical Support                  October 2002

  [13] Doria, A. and K. Sundell, "General Switch Management Protocol
  Applicability", RFC 3294, June 2002.


Acknowledgement

  This work was supported in part by the Korean Science and Engineering
  Foundation (KOSEF) through OIRC project


Author's Addresses

  Jun Kyun Choi
  Information and Communications University (ICU)
  58-4 Hwa Ahm Dong, Yusong, Daejon
  Korea 305-732
  Phone: +82-42-866-6122
  Email: jkchoi@icu.ac.kr

  Min Ho Kang
  Information and Communications University (ICU)
  58-4 Hwa Ahm Dong, Yusong, Daejon
  Korea 305-732
  Phone: +82-42-866-6136
  Email: mhkang@icu.ac.kr

  Jung Yul Choi
  Information and Communications University (ICU)
  58-4 Hwa Ahm Dong, Yusong, Daejon
  Korea 305-732
  Phone: +82-42-866-6208
  Email: passjay@icu.ac.kr

  Gyu Myung Lee
  Information and Communications University (ICU)
  58-4 Hwa Ahm Dong, Yusong, Daejon
  Korea 305-732
  Phone: +82-42-866-6231
  Email: gmlee@icu.ac.kr

  Young Wook Cha
  Andong National University (ANU)
  388 Song-Chon Dong, Andong, Kyungsangbuk-do
  Korea 760-749
  Phone: +82-54-820-5714
  Email: ywcha@andong.ac.kr

  Jeong Yun Kim
  Electronics and Telecommunications Research Institute (ETRI)
  161 KaJong-Dong, Yusong-Gu, Daejeon


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              GSMPv3 for Optical Support                  October 2002

  Korea 305-309
  Phone: +82-42-866-5311
  Email: jykim@etri.re.kr

  Hormuzd Khosravi
  Intel
  2111 NE 25th Avenue
  Hillsboro, OR 97124 USA
  Phone: +1 503 264 0334
  Email: hormuzd.m.khosravi@intel.com

  Georg Kullgren
  Nortel Networks AB
  S:t Eriksgatan 115 A
  P.O. Box 6701
  SE-113 85 Stockholm Sweden
  Email: geku@nortelnetworks.com

  Jonathan Sadler
  Tellabs Operations, Inc.
  1415 West Diehl Road
  Naperville, IL 60563
  Phone: +1 630-798-6182
  Email: Jonathan.Sadler@tellabs.com

  Stephen Shew
  Nortel Networks
  PO Box 3511 Station C
  Ottawa, ON
  K1Y 4H7
  Email: sdshew@nortelnetworks.com

  Kohei Shiomoto
  Email: Shiomoto.Kohei@lab.ntt.co.jp

  Atsushi Watanabe
  Nippon Telegraph and Telephone Corporation
  807A 1-1 Hikari-no-oka, Yokosuka-shi
  Kanagawa 239-0847, Japan
  Email: atsushi@exa.onlab.ntt.co.jp

  Satoru Okamoto
  Nippon Telegraph and Telephone Corporation
  9-11 Midori-cho 3-chome, Musashino-shi
  Tokyo 180-8585, Japan
  Email: okamoto@exa.onlab.ntt.co.jp

  Avri Doria
  Div. of Computer Communications
  Lulea University of Technology
  S-971 87 Lulea
  Sweden


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              GSMPv3 for Optical Support                  October 2002

  Phone: +1 401 663 5024
  EMail: avri@acm.org

  Fiffi Hellstrand
  Nortel Networks AB
  S:t Eriksgatan 115 A
  SE-113 85 Stockholm Sweden
  EMail: fiffi@nortelnetworks.com

  Kenneth Sundell
  Nortel Networks AB
  S:t Eriksgatan 115 A
  SE-113 85 Stockholm Sweden
  EMail: ksundell@nortelnetworks.com

  Tom Worster
  Phone: +1 617 247 2624
  EMail: fsb@thefsb.org


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