Fast Session Transfer Session Setup in TVWS

1. Fast Session Transfer Session Setup in TVWS Authors: Date: 2011-01-07 Bahareh Sadeghi et al, Intel Corp.

2. Abstract • Devices supporting TVWS radio in most cases will also support other Wi-Fi radios (2.4GHz, 5GHz and 60GHz) • Depending on the operating environment there is a need to be able to switch between these radios causing little or no impact to higher layer application performance. • Critical when the device is portable • This submission proposes a method to have a peer device start the TGad Fast Session Transfer Setup protocol to be usable in TVWS Bahareh Sadeghi et al, Intel Corp.

3. Mode I Device • Can Tx in a TVWS frequency if it sees a Mode II device on that channel • Cannot Tx until it sees an enabling signal from Mode II device • Needs to see a beacon or contact verification signal every 60 seconds to maintain Tx • Mode II Device • Inputs its location to the database and acquires allowed frequencies • Can pass on this frequency information to Mode I device that it is in communication with • Can initiate network with other Mode I devices Definitions Bahareh Sadeghi et al, Intel Corp.

4. Motivation: When does FST Session Setup comes into play? Distance from the AP Within the same room TGac/ad Across one or more rooms, to the edge of a large home a/b/g/n or ac in some cases Far edges of the yard, > 300m from the AP (a large church or auditorium); TGaf As the user moves between the room there is a need to keep the display application (~ 20Mbps goodput) work without any interruption. This means we need FST from .11ac/ad to .11a/b/g/n/ac to .11af and back. AP – Mode-II STA – Mode-1 Bahareh Sadeghi et al, Intel Corp.

5. TGad FST State Machine • TVWS Mode-I STAs cannot FST ACK or initiate a frame exchange in a channel in TVWS without the TVWS Mode-II device transitioning to operating in the selected TVWS channel and beaconing in it. • Need a mechanism to ensure that the FST session setup is initiated by the TVWS Mode-II device all the time. • Define a new action frame for TVWS Mode-I device to request TVWS Mode-II device to initiate FST Session setup Need a mechanism to ensure that the FST session setup is initiated by the TVWS Mode-II device all the time. Bahareh Sadeghi et al, Intel Corp.

6. TVWS FST Session Setup Bahareh Sadeghi et al, Intel Corp.

7. If the Mode-I device decides to transition to TVWS band, it sends the “Start FST Session Setup Request action frame” with the same parameter set that it would have used if it were to initiate FST Session Setup to the Mode-II device. Mode-2 devices responds with a success or failure using a Start FST Session Setup Response action frame If the Mode-2 device responds with a success, it also initiates the FST Session Setup ProposalStart FST Session Setup Request and Response action frames Bahareh Sadeghi et al, Intel Corp.

8. Proposed Action Frames Start FST Session Setup Request Start FST Session Setup Response Exactly the same as in Tgad FST Setup Request action frame Bahareh Sadeghi et al, Intel Corp.

9. Flow diagrams TVWS Mode-II device TVWS Mode-I device Start FST Session Setup Request Start FST Session Setup Response: Success Expected time to initiate FST Session setup (TUs) TGad FST Sesssion Setup Procedure TVWS Mode-II device TVWS Mode-I device Start FST Session Setup Request Start FST Session Setup Response: Fail Bahareh Sadeghi et al, Intel Corp.

10. FST Session Setup is critical to end user experience TGad FST Session Setup state machine does not change New Start FST Session Setup Request/Response action frames are defined Non TVWS implementations could use this mechanism to simplify FST Session Setup implementation, i.e. devices that choose never to be FST Session Setup initiators (as defined in TGad) Summary Bahareh Sadeghi et al, Intel Corp.

11. Do you agree that FST Session Setup is required for TVWS? • Y/N/Abstain • Do you support the proposed method to trigger FST Session Setup initiation at the peer device? • Y/N/Abstain Straw Polls Bahareh Sadeghi et al, Intel Corp.