January 2011
doc.: IEEE 802.11-11/0090r0
Fast Session Transfer Session Setup in TVWS
Date: 2011-01-07
Authors:
Name
Affiliations
Sadeghi, Bahareh Intel Corp.
Srikathyayani,
Srikanteswara
Venkatesan,
Ganesh
Submission
Intel Corp.
Address
Phone
th
2111 NE 25 Ave. 503 712 8367
Hillsboro OR 97229
2111 NE 25th Ave. 503 712 2286
Hillsboro OR 97229
2111 NE 25th Ave. 503 334 6720
Hillsboro OR 97229
Slide 1
email
[email protected]
m
srikanteswara.srikathyayan
[email protected]
[email protected]
om
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
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
Submission
Slide 2
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Definitions
•
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
Submission
Slide 3
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Motivation: When does FST Session Setup comes into play?
Distance from the AP
Across one or more rooms,
to the edge of a large home
a/b/g/n or ac in some cases
Within the
same room
TGac/ad
AP – Mode-II
STA – Mode-1
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.
Submission
Slide 4
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
TGad FST State Machine
•
•
•
TVWS Mode-I STAs
cannot FST ACK or
initiate a frame exchange
in a channel in TVWS
without the TVWS ModeII 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.
Submission
Slide 5
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
TVWS FST Session Setup
Mode-II Device
Mode-I
Submission
Current band
New band
.11a/b/g/n/ac/ad
TVWS
FST session setup
in .11a/b/g/n/ac/ad
TVWS
.11a/b/g/n/ac/ad
FST session setup
in TVWS
.11a/b/g/n/ac/ad
TVWS
Send Start FST
Session Setup
action frame to
Mode-2 device
TVWS
.11a/b/g/n/ac/ad
FST session setup
in TVWS
Slide 6
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Proposal
Start FST Session Setup Request and Response action frames
• 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
Submission
Slide 7
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Proposed Action Frames
Start FST Session Setup Request
Category
= FST
Action =
Start FST
Session
Setup
Request
Dialog
Token
LLT
1
1
1
4
Octets
Session
Transition
Multi-band
(optional)
Wakeup
Schedule
(optional)
Awake
Window
(optional)
Switching
Stream
(optional)
Resource/
capability
related
IEs
Start FST Session Setup Response
Octets
Catego
ry =
FST
Action =
Start FST
Session
Setup
Response
1
1
Dialog
Token
1
Status
Code =
Fail or
Success
2
Expected
time to
initiate
FST
Session
setup
(TUs)
2
LLT
Session
Transitio
n
Multiband
(optional)
Wakeup
Schedule
(optional)
Awake
Window
(optional)
Switchin
g Stream
(optional)
Resource/
capability
related
IEs
4
Exactly the same as in Tgad FST Setup
Request action frame
Submission
Slide 8
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Flow diagrams
TVWS Mode-II device
TVWS Mode-I device
TGad FST Sesssion Setup Procedure
TVWS Mode-II device
TVWS Mode-I device
Submission
Expected time to initiate FST
Session setup (TUs)
Slide 9
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Summary
• 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)
Submission
Slide 10
Bahareh Sadeghi et al, Intel Corp.
January 2011
doc.: IEEE 802.11-11/0090r0
Straw Polls
• 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
Submission
Slide 11
Bahareh Sadeghi et al, Intel Corp.