OPSAWG                                                           Y. Chen
Internet-Draft                                                    D. Liu
Updates: 5416 (if approved)                                      H. Deng
Intended status: Standards Track                            China Mobile
Expires: August 18, September 5, 2014                                      Lei. Zhu
                                                                  Huawei
                                                       February 14,
                                                           March 4, 2014

    CAPWAP Extension for 802.11n and Power/channel Autoconfiguration
                 draft-ietf-opsawg-capwap-extension-02
                 draft-ietf-opsawg-capwap-extension-03

Abstract

   The CAPWAP binding for 802.11 is specified by RFC5416 and it was
   based on IEEE 802-11.2007 standard.  After RFC5416 was published in 2009,
   there were several  Several new amendments of 802.11
   have been published. published since RFC5416 was published in 2009.  802.11n is
   one of those amendments and it has been widely used in real
   deployment.  This document extends the CAPWAP binding for 802.11 to
   support 802.11n and also defines a power and channel auto
   configuration extension.

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
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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on August 18, September 5, 2014.

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   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . .  Terminology . . . . . . .   3
   3.  Abbreviations . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.
   3.  CAPWAP 802.11n Support  . . . . . . . . . . . . . . . . . . .   3
     4.1.
     3.1.  CAPWAP Extension for 802.11n Support  . . . . . . . . . .   4
       4.1.1.
       3.1.1.  802.11n Radio Capability Information  . . . . . . . .   4
       4.1.2.
       3.1.2.  802.11n Radio Configuration Message Element . . . . .   4
       4.1.3.
       3.1.3.  802.11n Station Information . . . . . . . . . . . . .   6
   5.
   4.  Power and Channel Autoconfiguration . . . . . . . . . . . . .   7
     5.1.
     4.1.  Channel Autoconfiguration When WTP Power On . . . . . . .   7
     5.2.
     4.2.  Power Configuration When WTP Power On . . . . . . . . . .   8
     5.3.
     4.3.  Channel/Power Auto Adjusment  . . . . . . . . . . . . . .   8
       5.3.1.
       4.3.1.  IEEE 802.11 Scan Parameter Parameters Message Element . . . . . . . . . . .   9
       5.3.2.
       4.3.2.  IEEE 802.11 Channel Bind Message Element  . . . . . . . . . . . .  10
       5.3.3.  11
       4.3.3.  IEEE 802.11 Channel Scan Report . . . . . . . . . . . . . . . . .  11
       5.3.4.  12
       4.3.4.  IEEE 802.11 Neighbor WTP Report . . . . . . . . . . . . . . . . .  13
   6.  14
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   7.  14
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   8.  14
   7.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  14
   9.  15
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  14
   10.  15
   9.  Normative References  . . . . . . . . . . . . . . . . . . . .  14  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15  16

1.  Introduction

   IEEE 802.11n

   The 802.11-2009 [IEEE 802.11n.2009] standard was published in 2009 and it is as
   an amendment to the IEEE 802.11-2007 standard. standard to improve network
   throughput.  The maximum data rate increases to 600Mbps.  In the
   physical layer, 802.11n use OFDM uses Orthogonal Frequency Division
   Multiplexing (OFDM) and MIMO Multiple Input/Multiple Output (MIMO) to
   achieve the high throughput. 802.11n also use uses multiple antennas to form
   an antenna array which can be dynamically adjusted to improve the
   signal strength and extend the coverage.

   There are several capabilities

   Capabilities of 802.11n need to be supported by
   CAPWAP control message, such as radio capability, radio configuration
   and station information etc.  This document specifies the 802.11n and
   power/channel auto-configuration need to be supported by CAPWAP control
   messages.  The necessary extensions for CAPWAP.

   For the AC/WTP that does not support the extensions defined by this
   document, it can simply ignore the extensions purpose are introduced
   in Section 3 and will not cause any
   incompatible issue.

2.  Conventions used specified in Section 4.

   For IEEE 802.11 in general, it is desirable to be able to support
   power and channel auto reconfiguration.  Extensions for this document purpose
   are specified in Section 5.

2.  Terminology

   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 [RFC2119].

3.  Abbreviations

      AC:

   This document uses the following abbreviations:

      AC Access Controller
      A-MSDU:Aggregate
      A-MSDU Aggregate MAC Service Data Unit
      A-MPDU:Aggregate
      A-MPDU Aggregate MAC Protocol Data Unit
      MIMO: Multi-input Multi-output
      MSDU:
      AC Access Controller
      GI Guard Interval
      MCS Maximum Modulation and Coding Scheme
      MIMO Multiple Input/Multiple Output
      MPDU MAC Service Protocol Data Unit
      MPDU:
      MSDU MAC Protocol Service Data Unit
      MCS: Maximum Modulation and Coding Scheme
      OFDM:
      OFDM Orthogonal Frequency-Division Frequency Division Multiplexing
      WTP:
      TSF timing synchronization function
      WTP Wireless Termination Points.

4. Point

3.  CAPWAP 802.11n Support

   [IEEE-802.11.2009] standard was published in 2009 and it is an
   amendment of the IEEE 802.11-2007 standard to improve throughput.
   The maximum data rate increases to 600Mbps.  In the physical layer,
   802.11n use OFDM and MIMO to achieve high throughput. 802.11n use
   multiple antennas to form antenna array which can be dynamically
   adjusted to improve the signal strength and extend the coverage.

   802.11n support three modes

   802.11n supports three modes of channel usage: 20MHz mode, 40MHz mode
   and mixed mode. 802.11n has a new feature called channel binding.  It
   can bind two adjacent 20MHz channel to one 40MHz channel to improve
   the throughput.If using 40MHz channel configuration there will be
   only one non-overlapping channel in 2.4GHz. the 2.4GHz band.  In the large
   scale deployment scenario, the operator need needs to use 20MHz channel
   configuration in the 2.4GHz band to allow more non-overlapping
   channels.

   In the MAC layer, a new feature of 802.11n is Short Guard
   Interval(GI). 802.11a/g uses an 800ns guard interval between the
   adjacent information symbols.  In 802.11n, the GI can be configured
   to 400nm under good wireless condition. conditions.

   Another feature in the 802.11 MAC layer is Block ACK. 802.11n can use
   one ACK frame to acknowledge several MPDU MAC Protocol Data Unit (MPDU)
   receiving event. events.

   CAPWAP needs to be extended to support the above new 802.11n
   features.  For example,  CAPWAP should allow the access controller to know the
   supported 802.11n features of WTP and the access controller should be able
   to configure the different channel binding modes for
   WTP.

4.1. modes.  This document
   defines extensions of the CAPWAP 802.11 binding to support 802.11n
   features.

3.1.  CAPWAP Extension for 802.11n Support

   There are three

   Three 802.11n features need to be supported by CAPWAP 802.11 binding:
   802.11n radio capability, 802.11n radio configuration and station
   information.  This section defines the extension of the current
   CAPWAP 802.11 binding to support the 802.11n features.

4.1.1.

3.1.1.  802.11n Radio Capability Information

   [RFC5416] defines the IEEE 802.11 binding for the CAPWAP protocol.
   It defines the IEEE 802.11 Information Element (Type 1029) Element, which is used to
   communicate any IE information element (IE) defined in the IEEE 802.11
   protocol.  The detail
   definition of  This document specifies that the IEEE 802.11 Information
   Element is defined in section 6.6 of
   [RFC5416].  The [RFC5416] SHALL be used to
   transport the IEEE 802.11 HT information element is defined in section
   8.4.2.58 of [IEEE-802.11.2012].  It contains the 802.11n
   radio capability information.  This document specifies use of the
   IEEE 802.11 Information Element (Type 1029) transporting the IEEE
   802.11  The HT information element to carry the 802.11n radio capability
   information.  802.11n radio capability information IE MAY in this way be
   included in
   the CAPWAP Configuration Status Request/Response messages.

4.1.2.

3.1.2.  802.11n Radio Configuration Message Element

   The 802.11n Radio Configuration Information Element message element is used by the AC to configure
   provide IEEE 802.11n-specific configuration for a Radio on the WTP WTP,
   and by the WTP to deliver its radio configuration to the AC.  This
   supplements the IEEE 802.11 WTP WLAN Radio Configuration message
   element defined in [RFC5416].  The format of the 802.11n Radio
   Configuration Information Element message element is defined shown in figure Figure 1.  The 802.11n
   Radio Configuration Message Element message element MAY be included in the CAPWAP
   Configuration Update Request/Response 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Radio ID   |S|P|N|G|B|     |    MaxSup MCS | Max MandMCS   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    TxAntenna  |    RxAntenna  |         Reserved              |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 1: 802.11n Radio Configuration Message Element

   Type: TBD TBD1 for 802.11n Radio Configuration Message Element.

   Length: 16.

   Radio ID: An 8-bit value representing the radio, whose value is
   between one (1) and 31.

   S bit: A-MSDU Cfg: configuration: Enable/disable Aggregate MAC Service
   Data Unit (A-MSDU).  Set to 0 if disabled.  Set to 1 if enabled.

   P bit: A-MPDU Cfg: configuration: Enable/disable Aggregate MAC Protocol
   Data Unit (A-MPDU).  Set to 0 if disabled.  Set to 1 if enabled.

   N bit: 11n Only Cfg: configuration: Whether to allow only 11n user access.
   Set to 0 if allow non-802.11n user access. access is allowed.  Set to 1 if do not allow
   non-802.11n user access. access is not allowed.

   G bit: Short GI Cfg: configuration: Set to 0 if Short Guard Interval is
   disabled.  Set to 1 if enabled.

   B bit: Bandwidth Cfg: Bandwidth binding mode. mode configuration: Set to 0 if 40MHz
   binding mode.  Set to 1 if 20MHz binding mode.

   MaxSup

   Maximum supported MCS: Maximum Modulation and Coding Scheme (MCS)
   index.  It indicates the maximum MCS index that the WTP or the STA
   can support.

   Max Mandatory MCS: Maximum Mandatory Modulation and Coding Scheme
   (MCS) index.  Mandatory rates must be supported by the WTP and the
   STA that want to associate with the WTP.

   TxAntenna: Transmitting antenna configuration.  Each TxAntenna bit
   represent
   represents a certain number of antennas.  Set to 1 if enabled, set to
   0 if disabled.

   RxAntenna: Receiving antenna configuration.  Each RxAntenna bit
   represent
   represents a certain number of antennas.  Set to 1 if enabled, set to
   0 if disabled.

   The detail definition of TxAntenna/RxAntenna is as follows:

                        0 1 2 3 4 5 6 7
                       +-+-+-+-+-+-+-+-+
                       |8|7|6|5|4|3|2|1|
                       +-+-+-+-+-+-+-+-+

   Figure 2: Definition of TxAntenna/RxAntenna
   Each bit when enabled will represent the number of antennas
   correspondent to that bit.  Only one bit is allowed to be set to 1.
   For example, when the first bit is enabled,it represents 8 antennas.

4.1.3.

3.1.3.  802.11n Station Information

   The 802.11n Station Information message element is used to deliver
   IEEE 802.11n station policy from the AC to the WTP.  The definition
   of the 802.11n Station Information message element is in figure 3.
   The format of 802.11n Station Information MAY be included in the
   CAPWAP Station Configuration Request 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                          MAC Address                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |            MAC Address        |S| P |T|F|H|M| |  Max RxFactor |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Min StaSpacing|       HiSuppDataRate          | AMPDUBufSize  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | AMPDUBufSize  |    HtcSupp    |           MCS Set             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   MCS Set                                                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   MCS Set                                                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 3: 802.11n Station Information

   MAC Address: The station's MAC Address.

   Type: TBD TBD2 for 802.11 Station Information.

   Length: 24.

   S bit: SupChanl width: Supporting bandwidth mode.  0x00: 20MHz bandwidth mode.  0x01:
   40MHz bandwidth binding mode.

   P flag: Power Save: Saving mode: 0x00: Static power saving mode. Static.  0x01: Dynamic
   power saving mode. Dynamic.  0x03: Do
   not support power saving mode.

   T bit: ShortGi20: Whether to support short GI in 20MHz bandwidth mode.  0x00: Do
   not support short GI.  ox01:  0x01: Support short GI.

   F bit: ShortGi40: Whether to support short GI in 40MHz bandwidth
   mode.  0x00: Do not support short GI.  ox01:  0x01: Support short GI.

   H bit: HtDelyBlkack: Whether block Block Ack support supports delay mode.  0x00: Do not support
   delay mode.  0x01: Support delay mode.

   M bit: Max Amsdu: The maximal AMSDU A-MSDU length.  0x00: 3839 bytes.  0x01: 7935
   bytes.

   Max RxFactor: The maximal receiving AMPDU A-MPDU factor.

   Min StaSpacing: Minimum MPDU Start Spacing.

   HiSuppDataRate: Maximal transmission speed (Mbps).

   AMPDUBufSize: AMPDU A-MPDU buffer size. size (Byte).

   HtcSupp: Whether the packet have to place HT header. headers on the packets forwarded from
   this station.

   MCS Set: The MCS bitmap that the station supports.

5.

4.  Power and Channel Autoconfiguration

   Power and channel autoconfiguration could avoid potential radio
   interference and improve the WLAN performance.  In general, the auto-
   configuration of radio power and channel could occur at two stages:
   when the WTP power on or during the WTP running time.

5.1.

4.1.  Channel Autoconfiguration When WTP Power On

   When the

   Power and channel auto reconfiguration avoids potential radio
   interference and improves the WLAN performance.  In general, the
   auto- configuration of radio power and channel can occur at two
   stages: when the WTP powers on or while the WTP is power-on, it in running state.
   When the WTP is of necessity powered-on, it needs to configure a proper
   channel to the WTP in order to achieve best status of radio links. channel.
   IEEE 802.11 Direct Sequence Control elements or IEEE 802.11 OFDM
   Control element defined in RFC5416 SHOULD be carried in the Configure
   Status Response message to offer WTP a channel at this stage.  If the
   channel field of those information element is zero, set to 0, the WTP will
   need to determine its channel by itself, otherwise the WTP SHOULD be
   configured according to the provided information element.

   When the WTP determines its own channel configuration, it should
   first scan the channel information, then determine which channel it
   will work on and form a channel quality scan report.  As shown in
   Figure 3, the AC can control the scanning process by sending the IEEE
   802.11 Scan Parameters message element defined in Section 5.1 to the
   WTP in a Configure Status Response message or in a WTP Configure
   Update Request message.  The WTP will send the channel quality report will be sent
   to the AC using the WTP Event Request message
   by the WTP. message.

   AC will determine whether to change the channel configuration based
   on the received channel quality report.  The AC can MAY use a IEEE 802.11
   Direct Sequence Control or IEEE 802.11 OFDM Control information message element
   carried by the configure Update Request message to configure a new
   channel for the WTP.

5.2.

4.2.  Power Configuration When WTP Power On

   The IEEE 802.11 Tx Power information message element defined in section 6.18 of
   [RFC5416] is used by the AC to control the transmission power of the
   WTP.  The 802.11 Tx Power information element is carried in the
   Configure Status Response message or in the Configure Update Request
   message.

5.3.

4.3.  Channel/Power Auto Adjusment

   The Channel Scan Procedure is illustrated by the figure 4.

                  WTP              Configure Status Req                 AC
                  ------------------------------------------------------->
    Configure Status Res(Scan Parameter Message Element, Channel Bind Message Element)
                  <------------------------------------------------------
                or

                WTP                                                     AC
    Configure Update Req(Scan Parameter Message Element, Channel Bind Message Element )
                  <-----------------------------------------------------
                                  Configure Update Res
                  ----------------------------------------------------->

   Figure 4: Channel Scan Procedure

   The WTP has two working modes, the first one is work modes: normal working mode and scan only mode.  In
   this
   normal mode, the WTP can provide service for station access and scan
   channels at the channel while providing the service
   to STA. same time.  Whether the WTP will provide scanning service scan a given set of
   channels is determined by the Max Cycles value of field in the IEEE 802.11
   Channel Bind Message Element.  If message element defined in Section 5.2.  When this value
   equls field
   is set to zero, 0, the WTP will not perform scanning. scan the channel.  If this value
   equls field is set
   to 255, the WTP will scan the channel continuously until
   getting notification from AC.  Otherwise, continuously.  The type of the
   scan is determined by the Scan Type field.  With the passive scan
   type, the WTP monitors the air interface, using the received beacon
   frames to determine the nearby WTPs.  With the active scan type, the
   WTP will perform
   scanning with send a probe message and receive probe response messages.

   In the number that specified normal scan mode, the value of Max Cycles.  The
   second working mode WTP behaviour is scan only mode. controlled by three
   parameters: PrimeChlSrvTime, OnChannelScanTIme, and
   OffChannelScnTIme.  These are provided by the IEEE 802.11 Scan
   Parameters message element defined in Section 5.1.  The WTP will not
   provide access service for stations for the duration given by
   PrimeChlSrvTime.  It then scans the working channel for the duration
   given by OnChannelScnTime.  It returns to STA in this case.  In this mode, WTP will scan servicing station access
   requests on the working channel
   continuously. for another period of length
   PrimeChlSrvTime, then moves to a different channel and scans it for
   duration OffChannelScnTIme.  It repeats this cycle, scanning a new
   non-working channel each time, until all the channels have been
   scanned.

   When the WTP work works in the scan only mode, there is no difference it does not distinguish between
   the working channel and scan channel.  Every channel's scan duration
   will be OffChannelScnTime and the PrimeChlSrvTime and OnChannelScanTime is
   MUST be set to 0.

   There are two

   As shown in Figure 4, the AC can control the scan types which is determined behaviour at the
   WTP by including the IEEE 802.11 Scan Type value.
   The first type is passive scan.  The Parameters and IEEE 802.11
   Channel Bind message elements in a Configure Status Response or WTP will listen
   Configure Update Request message.

   Scan Report.  After completing its scan, the channel
   passively in this case.  The other type is active scan.  The WTP will MAY send probe for the scan.  There are three parameters that will
   determine scan
   report to the working mode of scan: PrimeChlSrvTime, On Channel
   ScanTime, Off Channel ScanTime.  The AC using a WTP will provide service for the
   period of "PrimeChlSrvTime" time then start channel Event Request message.  The scan for report
   information is carried in the
   period of "On IEEE 802.11 Channel ScanTime" time; then continue to provide
   service for the period of "PrimeChlSrvTime" time; then leave the
   current working channel Scan Report message
   element (Section 5.3) and scan next channel for the period an instance of "Off
   Channel ScanTime" time; then provide service on the next channel for the period IEEE 802.11 Information
   Element message element carrying a copy of "PrimeChlSrvTime"..until finishing the scan procedure.

5.3.1. theIEEE 802.11 Neighbor
   WTP Report information element (Section 5.4).

4.3.1.  IEEE 802.11 Scan Parameter Parameters Message Element

   The definition format of the IEEE 802.11 Scan Para Parameters Message Element is as follows:
   shown in Figure 5:

             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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |    Radio ID   |M|S|L|D|       |         Report Time           |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |      PrimeChlSrvTime          |     On Channel ScanTime       |
            +-------------------------------+-------------------------------+
            |   Off Channel ScanTime        |
            +-------------------------------+

   Figure 5: IEEE 802.11 Scan Parameter Parameters Message Element

   Type: TBD TBD3 for IEEE 802.11 Scan Parameter Parameters Message Element.

   Length: 10.

   Radio ID: An 8-bit value representing the radio, whose value is
   between one (1) and 31.

   M bit: AP oper mode: the work Work mode of the WTP. 0x01:normal 0x00:normal mode.
   0x02: 0x01: monitor only
   mode, no service is provided in this mode.ss mode.

   S bit: Scan Type: 0x01: 0x00: active scan; 0x02: 0x01: passive scan.

   L bit: L=1: Open Load Balance Scan.  L=0: Disable Load Balance Scan.

   D bit: D=1: Open Rogue WTP detection scan.  D=0: Disable Rouge WTP
   detection scan.

   Report Time: Channel quality report time (unit: second).

   PrimeChlSrvTime: Service time (unit: millisecond) on the working scan
   channel.  This segment is invalid(set to 0) when WTP oper mode is set
   to 2. 1.  The maximum value of this segment is 10000, the minimum value
   of this segment is 5000, the default value is 5000.

   On Channel ScanTime: The scan time (unit: millisecond) of the working
   channel.  When the WTP oper mode is set to 2, this segment is
   invalid(set to 0).  The maximum value of this segment is 120, the
   minimum value of this segment is 60, the default value is 60.

5.3.2.

   Off Channel ScanTime: The scan time (unit: millisecond) of the
   working channel.  When the WTP operating mode is set to 2, this
   segment MUST be set to 0.  The maximum value of this segment is 120,
   the minimum value of this segment is 60, the default value is 60.

4.3.2.  IEEE 802.11 Channel Bind Message Element

   The definition format of the IEEE 802.11 Channel Bind Message ELement Element 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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |   Radio ID   Flag        |   Max Cycles  |Channel Count  |ScanChannelSet.|
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 6: IEEE 802.11 Channel Bind Message Element

   Type: TBD TBD4 for IEEE 802.11 Channel Bind Message Element.

   Length: 4.

   Radio ID: An 8-bit value representing the radio, whose value is
   between one (1) and 31.

   Flag: bitmap, reserved.

   Max Cycles: Scan repeat times. Number of times the scanning cycle is repeated for the
   set of channels identified by this message element. 255 means
   continuous scan.

   Channel Count: The number of channel channels will be scanned.

   Scan Channel Set: The channel information. identifies the members of the set of channels to
   which this message element instance applies.  The format for each
   channel 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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |            Channel ID          |              Flag            |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 7: Channel Information Format

   Channel ID: the channel ID of the channel which will be scanned.

   Flag: Bitmap, reserved for future use.

5.3.3.

4.3.3.  IEEE 802.11 Channel Scan Report

   There are two types of scan report: Channel Scan Reprot and Neighbor
   STA Reprot.  Channel Scan Report is used to channel autoconfiguration
   while Neighbor WTP Report is used to power autoconfiguration.  The
   WTP send the scan report to the AC through WTP Event Request message.
   The information element that used to carry the scan report is Channel
   Scan Report Message Element and Neighbor WTP Report Message Element.

   The definition format of the IEEE 802.11 Channel Scan Report Message Element message element is
   in
   figure Figure 8.

             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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            | Radio ID     | Report Count    |    Channel Scan Report       |
            +---------------------------------------------------------------+

   Figure 8: IEEE 802.11 Channel Scan Report Message Element

   Type: TBD TBD5 for IEEE 802.11 Channel Scan Report Message Element. message element.

   Length: >=29.

   Radio ID: An 8-bit value representing the radio, whose value is
   between one (1) and 31.

   Report Count: The channel number will be reported. of channels for which a report is provided.

   Channel Scan Report: The definition format of the each Channel Scan Report is shown
   in
   figure Figure 9.  It complies with the IEEE 802.11 Beacon report that
   defined in section 8.4.2.24.7 of [IEEE-802.11.2012].

             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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |Operating Class|Channel Number |Actual Measurement Start Time..|
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |        ...Actual Measurement Start Time                       |
            |-------------------------------+-------------------------------+
            |..Actual Measurement Start Time|    Measurement Duration       |
            +---------------+---------------+-------------------------------+
            |Reported Frame |    RCPI       |      BSSID...                 |
            +---------------+---------------+-------------------------------+
            |                         ...BSSID                              |
            +---------------+-----------------------------------------------+
            | Antena Antenna ID    |          Parent TSF...                        |
            +---------------+-----------------------------------------------+
            |...Parent TSF  | Optional Subelements(variable) Sub-elements(variable)               |
            +---------------+-----------------------------------------------+

   Figure 9: Channel Scan Report

   Operating Class: Indicates the channel set for which the measurement
   request applies.  The definition of this field complies with the
   definition in section 8.4.2.24.7 of [IEEE-802.11.2012].

   Channel Number: Indicates the channel number for which the
   measurement report applies.  The definition of this field complies
   with the definition in section 8.4.2.24.7 of [IEEE-802.11.2012].

   Actual Measurement Start Time: Is set to the value of the measuring
   STA's
   station's TSF timer at the time the measurement started.

   Measurement Duration: Is set to the duration over which the Beacon
   Report was measured.  The definition of this field complies with the
   definition in section 8.4.2.24.7 of [IEEE-802.11.2012].

   Reported Frame Information: This field contains two subfields as
   defined in [IEEE-802.11.2012].

   RCPI: Indicates the received channel power of the Beacon, Measurement
   Pilot, or Probe Response frame.

   RSNI:Indicates the received signal to noise indication for the
   Beacon, Measurement Pilot, or Probe Response frame.

   BSSID: This field contains the BSSID from the Beacon,Measurement
   Pilot, or Probe Response frame being reported.

   Antenna ID: This field contains the identifying number for the
   antennas used for this measurement.

   Parent TSF: This field contains the lower 4 octets of the measuring
   STA's
   station's TSF timer value at the start of reception of the first
   octet of the timestamp field of the reported Beacon, Measurement
   Pilot, or Probe Response frame at the time the Beacon frame being
   reported was received.

   Optional Subelements: This field contains zero or more subelements.

5.3.4.

4.3.4.  IEEE 802.11 Neighbor WTP Report

   The neighbor

   This document specifies that the WTP report message element is composed MAY include an instance of the
   IEEE 802.11 Information Element that defined in section 6.6 of [RFC5416]
   and IEEE 802.11 Neighbor Report Element that defined in section 8.4.2.39 of [IEEE-802.11.2012].  The Neighbor Report Element is
   carried by the
   [IEEE-802.11.2012]  within IEEE 802.11 Information Element message
   element defined in section 6.6 of [RFC5416] to form the neighbor
   WTP report message element.

6. neighbouring
   WTP information to the AC.

5.  Security Considerations

   This document is based on RFC5415/RFC5416 and it doesn't increase any
   security risk.  The adds no new security considerations of this document aligns
   with RFC5415/5416.

7.
   considerations.

6.  IANA Considerations

   The extension defined in this document need to extend CAPWAP IEEE
   802.11 binding message element which is defined in section 6 of
   [RFC5416].  The following IEEE 802.11 specific message element type
   need to be defined by IANA.

   TBD1: 802.11n Radio Configuration Message Element type value
   described in section 4.1.2.

   TBD2: 802.11n Station Message Element type value described in section
   4.1.3.

   TBD3: 802.11 Scan Parameter Message Element type value described in
   section 5.3.1.

   TBD4: 802.11 Channel Bind Message Element type value described in
   section 5.3.2.

   TBD5: Channel Scan Report Message Element type value described in
   section 5.3.3.

8.

7.  Contributors

   This draft is a joint effort from the following contributors:

   Gang Chen: China Mobile chengang@chinamobile.com

   Naibao Zhou: China Mobile zhounaibao@chinamobile.com

   Chunju Shao: China Mobile shaochunju@chinamobile.com

   Hao Wang: Huawei3Come hwang@h3c.com

   Yakun Liu: AUTELAN liuyk@autelan.com

   Xiaobo Zhang: GBCOM

   Xiaolong Yu: Ruijie Networks

   Song zhao: ZhiDaKang Communications

   Yiwen Mo: ZhongTai Networks

9.

   Dorothy Stanley: dstanley1389@gmail.com

   Tom Taylor: tom.taylor.stds@gmail.com

8.  Acknowledgements

   The authors would like to thanks Ronald Bonica,Romascanu Dan, Benoit
   Claise, Melinda Shore and Margaret Wasserman for their useful
   suggestions.  The authors also thanks Dorothy Stanley and Tom Taylor
   for their review and useful comments.

10.

9.  Normative References

   [IEEE-802.11.2009]
              "IEEE Standard for Information technology -
              Telecommunications and information exchange between
              systems Local and metropolitan area networks - Specific
              requirements Part 11: Wireless LAN Medium Access Control
              (MAC) and Physical Layer (PHY) Specifications", 2009.

   [IEEE-802.11.2012]
              "IEEE Standard for Information technology -
              Telecommunications and information exchange between
              systems Local and metropolitan area networks - Specific
              requirements Part 11: Wireless LAN Medium Access Control
              (MAC) and Physical Layer (PHY) Specifications", March
              2012.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4564]  Govindan, S., Cheng, H., Yao, ZH., Zhou, WH., and L. Yang,
              "Objectives for Control and Provisioning of Wireless
              Access Points (CAPWAP)", RFC 4564, July 2006.

   [RFC5415]  Calhoun, P., Montemurro, M., and D. Stanley, "Control And
              Provisioning of Wireless Access Points (CAPWAP) Protocol
              Specification", RFC 5415, March 2009.

   [RFC5416]  Calhoun, P., Montemurro, M., and D. Stanley, "Control and
              Provisioning of Wireless Access Points (CAPWAP) Protocol
              Binding for IEEE 802.11", RFC 5416, March 2009.

Authors' Addresses

   Yifan Chen
   China Mobile
   No.32 Xuanwumen West Street
   Beijing  100053
   China

   Email: chenyifan@chinamobile.com

   Dapeng Liu
   China Mobile
   No.32 Xuanwumen West Street
   Beijing  100053
   China

   Email: liudapeng@chinamobile.com
   Hui Deng
   China Mobile
   No.32 Xuanwumen West Street
   Beijing  100053
   China

   Email: denghui@chinamobile.com

   Lei Zhu
   Huawei
   No. 156, Shi-Chuang-Ke-Ji-Shi-Fan-Yuan Beiqing Road, Haidian District
   Beijing 100095
   China

   Email: lei.zhu@huawei.com