doc.: IEEE 802.11-11/xxxxr0

July 2011

Padam Kafle, NokiaSubmission

Simplification of Enablement Procedure for TVWS

Authors:

Date: July 18, 2011

Name Company Address Phone email

Padam Kafle Nokia 6021 Connection Drive, Irving, TX, 75039 +1 214 673 6232 Padam.kafle@nokia.com

Mika Kasslin Nokia Itämerenkatu 11-13, 00180 Helsinki, Finland +358 50 4836294 Mika.kasslin@nokia.com

Prabodh Varshney Nokia6021 Connection Drive, Irving, TX, 75039 +1 469 9512745 Prabodh.varshney@nokia.com

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 2

• There are many comments seeking clarification or changes on DSE enablement for TVWS band. This presentation try to cover the issues raised by the following CIDs on enablement in TVWS band:

CIDs: 3, 136, 138, 162, 321, 322, 326, 492, 502, 503, 505, 510, 511, 512, 513, 528, 529, 545, 553, 578, 579, 614, 905, 982

• Resolution: the resolution text to be provided in Doc: 11-11-0414r5.

Summary

503 DSE enablement and deenablement procedures are not necessary for TVWS band operation, as per the currently available regulations. All that is sufficient is to hear an enabling signal transmitted by an AP before starting any transmissions by client STAs in TVWS band, and continue receiving contact verification signal once a client STA receives available channel map.

Since the "dependent STA" and "Enabling STA" are used in relation to Enabling signal, these terms can still be useful. However, remove the requirements of DSE enablement procedure for a dependent STA while operating in TVWS band. DSE procedures as specified in Clause 10.12 are strictly applicable only for 3650-3700 MHz band operation. There are many conflicting procedures not required in TVWS band.

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 3

Contents

• Introduction• Overview of Terminologies• Enablement Procedure for TVWS band• Discussions and options

• Backup slides– Summary from FCC Rules– Some Remarks on 802.11y Operation

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 4

• The Dynamic Station Enablement (DSE) from 802.11y amendment has been adopted to 802.11af as a basis for controlling client stations

• However, there are many different requirements on network initiation and operation in TVWS band compared to licensed operation in 3650-3700 MHz band for which the existing DSE procedures were first introduced

• To improve the clarity and simplify the operation in TVWS band under the control of a geo-location database, a new clause is proposed instead of amending existing DSE procedures in clause 10.12

Introduction

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 5

What are new terms for TVWS?• GDC: Geo-location Database Control

• The operation of Mode II/Fixed TVBDs are directly controlled• The operation of Mode I TVBDs are indirectly controlled through a Mode II/Fixed

• GDC Enabling STA• A STA that can access a GDB, and is authorized to initiate a network in the TVWS band. A GDC

Enabling STA can enable other GDC dependent STAs to operate in the TVWS band. • GDC Dependent STA

• A STA that is authorized to transmit in TVWS band only after being enabled by a GDC Enabling STA

• GDC Enabling Signal• Beacon or probe response frame containing geodatabase inband enabling signal

• GDC Verification Signal• Contact verification signal in current draft

Terminologies related to Enablement in TVWS band

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 6

• 11-11-414r4 had proposed a new subclause for enablement in TVWS band instead of using DSE procedures (802.11y) , with the following basic steps:

1) GDC dependent STA must hear enabling signal before it can transmit in TVWS band2) GDC dependent STA sends CAQ Request to obtain valid channel list

• The GDC dependent STA may perform secure authentication /association with the GDC enabling STA/AP to meet security requirements in some regulations (FCC)

• The GDC enabling STA/AP sends response to CAQ request with valid channel list3) During operation of GDC dependent STA:

• Continue receiving CVS once at least every 60 s (dot11ContactVerificationSignalInterval)• GDC dependent STA must perform according to all control procedures required by its GDC

enabling STA (e.g. channel and power changes)

• During discussion, there were some suggestions to create separate frame for enablement exchange instead of using CAQ during step (2)• Separate procedures for enablement from channel availability query • CAQ for the purpose of a channel request can happen any time during the operation

Enablement Procedure for TVWS band

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 7

Enablement Procedure from 11-414r4

GDC Enabling STA/APGDC Dependent STA

Enabling Signal Phase

Enablement Phase

GDC Enabling Signal

Verification Phase

Unenabled

AttemptingEnablement

Contact Verification Signal

Channel Availability Query Request

Channel Availability Query Response

Enabled

.

.

.

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 8

Proposed alternative # 1GDC Enabling STA/APGDC Dependent STA

Enabling Signal Phase

Enablement Phase

GDC Enabling Signal

Verification Phase

Unenabled

AttemptingEnablement

Contact Verification Signal

Enabled

.

.

.

GDC Enablement Request

GDC Enablement Response

Public action frame with device ID info

Success if device ID verification is okay

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 9

Proposed alternative # 2GDC Enabling STA/APGDC Dependent STA

Enabling Signal Phase

Enablement Phase

GDC Enabling Signal

Verification Phase

Unenabled

AttemptingEnablement

Contact Verification Signal

Enabled

.

.

.

GDC Enablement Request

GDC Enablement Response

Public action frame with device ID info

Success if device ID verification is okay

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 10

Proposed alternative # 3GDC Enabling STA/APGDC Dependent STA

Enabling Signal Phase

Enablement Phase

GDC Enabling Signal

Verification Phase

Unenabled

AttemptingEnablement

Contact Verification SignalEnabled

.

.

.

GDC Enablement Request

GDC Enablement Response

Public action frame with device ID info

Success with WSM information if device ID verification is okay

.

.

.

CAQ is transmitted if WSM change is indicated or GDC-D

STA wants to obtain current WSM for any other reasons (e.g. after

PS)

The GDC Dependent STA need to maintain a timer (dot11GDCEnablementValidityTimer) to continue in Enabled state, by receiving CVS periodically, and transmitting CAQ to obtain valid channel list

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 11

Unenabled

AttemptingEnablement

Enabled

Receive GDC Enabling Signal

Failure to receive valid CVS from its GDC enabling STAwithin ContactVerificationSignalInterval during awake state

Receive CAQ response with request declined or not successful

GDC Enablement response with request declined or not successful

GDC enablement response with Device ID Verification Failure, or Failed enablement attempt

within dot11GDCEnablementTimeLimit

Wait fordot11GDCEnablementFailHoldTime

GDC enablement response with WSM for Success result

CVS with changed MAP ID or became awake after PS ?

Y

N

Transmit CAQ Request

Success with valid channel list result ?

Y

GDC-D STA state diagram for proposed alternative # 3

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 12

GDC-D STA state diagram for proposed alternative # 3 (in 11-11-414r5)

Unenabled

AttemptingGDCEnablement

GDCEnabled

Receive GDC Enabling Signal

dot11GDCEnablementValidityTimer has expired

Receive GDC Enablement Response frame with Status code set to 78 (Authorization Deenabled )

Receive GDC Enablement Response with Status code 1 or 38

Receive GDC Enablement Response with Status code Set to 77, or Failed enablement attempt within

dot11GDCEnablementTimeLimit

Wait fordot11GDCEnablementFailHoldTime

Receive GDC Enablement Response with Status

code set to 0 ( Successful)

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 13

Backup Slides

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 14

• What are the security requirements relevant to 802.11 air interface for FCC ID validation and channel query exchange?

Security (15.711 (f) (iii) Communications between a Mode I device and a fixed or Mode II device for

purposes of obtaining a list of available channels shall employ secure methods that ensure against corruption or unauthorized modification of the data. When a Mode I device makes a request to a fixed or Mode II device for a list of available channels the receiving device shall check with TV bands database that the Mode I device has a valid FCC Identified before providing a list of available channels. Contact verification signals transmitted for Mode I devices are to be encoded with encryption to secure the identity of the transmitting device. Mode I devices using contact verification signals shall accept as valid for authorization only the signals of the device from which they obtained their list of available channels.

• Data protection against corruption and interception• Certified devices (FCC ID): integrity or authenticity of a device may need

certificate based device authentication• Can existing 802.11 authentication be sufficient?

Impact due to FCC’s Security Requirements

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 15

Enabling Signal Rules • Enabling signal/control signal/contact seeking signal look very similar

• In § 15.202 Certified operating frequency range. “ For the purposes of this section, a master device is defined as a device operating in a mode in which it has the capability to transmit without receiving an enabling signal. In this mode it is able to select a channel and initiate a network by sending enabling signals to other devices.”

• In § 15.703 (c) Fixed devices “ A fixed TVBD may select channels for operation itself from a list of available channels provided by a TV bands database, initiate and operate a network by sending enabling signals to one or more fixed TVBDs and/or personal/portable TVBDs.”

• In § 15.703 (g) Network initiation. “The process by which a fixed or Mode II TVBD sends control signals to one or more fixed TVBDs or personal/portable TVBDs and allows them to begin communications”

• In § 15.711 (b) (3) (iv), “To initiate contact with a fixed or Mode II device, a Mode I device may transmit on an available channel used by the fixed or Mode II TVBD or on a channel the fixed or Mode II TVBD indicates is available for use by a Mode I device on a signal seeking such contacts.”

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 16

• Contact Verification Signal: • In § 15.703 (b) Contact verification signal: “An encoded signal broadcast by a fixed or Mode II device

for reception by Mode I devices to which the fixed or Mode II device has provided a list of available channels for operation. Such signal is for the purpose of establishing that the Mode I device is still within the reception range of the fixed or Mode II device for purposes of validating the list of available channels used by the Mode I device and shall be encoded to ensure that the signal originates from the device that provided the list of available channels. A Mode I device may respond only to a contact verification signal from the fixed or Mode II device that provided the list of available channels on which it operates. A fixed or Mode II device shall provide the information needed by a Mode I device to decode the contact verification signal at the same time it provides the list of available channels.”

• § 15.711 (b) (3) (iv) Mode I Operation: “At least once every 60 seconds, except when in sleep mode, i.e., a mode in which the device is inactive but is not powered-down, a Mode I device must either receive a contact verification signal from the Mode II or fixed device that provided its current list of available channels or contact a Mode II or fixed device to re-verify/re-establish channel availability. A Mode I device must cease operation immediately if it does not receive a contact verification signal or is not able to re-establish a list of available channels through contact with a fixed or Mode II device on this schedule.”

• § 15.711 (f) (iii) Security: “Contact verification signals transmitted for Mode I devices are to be encoded with encryption to secure the identity of the transmitting device. Mode I devices using contact verification signals shall accept as valid for authorization only the signals of the device from which they obtained their list of available channels.”

Contact Verification Signal Rules ..

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 17

Some Remarks on 802.11y Operation

• In 3650-3700 MHz band, the operation requires licensing:– Licensing fee to each operator for nationwide permission to operate – Additional fee for each high powered base station to be installed

• The enabling STA is a licensed base station that can transmit enabling signals to dependent STA or dependent AP over 3650 MHz or any other band

- The enablement requests and grants can also be exchanged through Internet or any other connectivity

- No concept of a dependent AP transmitting enabling signal (can not be relayed)• Interference resolution is possible by means of unique identifiers assigned to each

dependent STA and location of the enabling STA. Dependent STA only broadcast the location of the station that enabled it, plus the unique id they obtain from the enabling STA

• DSE service area boundary is controlled to the area where enabling signal can be received (initially, as well as, during operation)

doc.: IEEE 802.11-11/xxxxr0

July 2011

Submission Padam Kafle, NokiaSlide 18

Some Remarks on 802.11y Operation

• Dependent STA state machine from 802.11y