U.S. patent application number 14/670204 was filed with the patent office on 2015-10-01 for dedicated channel for fast initial link setup in a wireless network.
The applicant listed for this patent is QUALCOMM Incorporated. Invention is credited to Santosh Paul Abraham, George Cherian, Abhishek Pramod Patil.
Application Number | 20150282064 14/670204 |
Document ID | / |
Family ID | 54192379 |
Filed Date | 2015-10-01 |
United States Patent
Application |
20150282064 |
Kind Code |
A1 |
Patil; Abhishek Pramod ; et
al. |
October 1, 2015 |
DEDICATED CHANNEL FOR FAST INITIAL LINK SETUP IN A WIRELESS
NETWORK
Abstract
An access point may advertise (e.g., broadcast) identifying
information (e.g., a neighbor report and access point capability
information) on a dedicated channel in a wireless network. The
identifying information may include information about neighboring
access points in the wireless network. The neighboring access
points may operate on the dedicated channel, a different primary
operating channel, or a combination thereof. A station entering the
wireless network may scan the dedicated channel to detect the
identifying information from the access point to aid relatively
quick discovery of the neighboring access points without scanning
multiple channels.
Inventors: |
Patil; Abhishek Pramod; (San
Diego, CA) ; Cherian; George; (San Diego, CA)
; Abraham; Santosh Paul; (San Diego, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QUALCOMM Incorporated |
San Diego |
CA |
US |
|
|
Family ID: |
54192379 |
Appl. No.: |
14/670204 |
Filed: |
March 26, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61972851 |
Mar 31, 2014 |
|
|
|
Current U.S.
Class: |
370/329 |
Current CPC
Class: |
H04W 48/10 20130101;
H04W 48/14 20130101; H04W 36/0061 20130101; H04W 72/0433 20130101;
H04W 48/20 20130101 |
International
Class: |
H04W 48/20 20060101
H04W048/20; H04W 72/04 20060101 H04W072/04 |
Claims
1. A method comprising: scanning, at a first station, a dedicated
channel in a wireless network to detect broadcasted information
from an access point in the wireless network; and obtaining
identifying information regarding a particular identifiable access
point from the broadcasted information, the broadcasted information
including a neighbor report, access point capability information,
or a combination thereof, and wherein the access point capability
information is carried in a fast initial link setup (FILS)
indication element according to an Institute of Electrical and
Electronics Engineers (IEEE) 802.11ai protocol.
2. The method of claim 1, wherein the neighbor report includes a
reduced neighbor report according to the IEEE 802.11ai
protocol.
3. The method of claim 1, wherein the access point capability
information includes access point security information associated
with the particular identifiable access point and higher layer
capability information indicating higher layer capabilities of the
particular identifiable access point.
4. The method of claim 1, wherein the neighbor report is included
in one of a beacon frame broadcasted from the access point via the
dedicated channel, a FILS discovery frame broadcasted from the
access point via the dedicated channel, or a probe response from
the access point.
5. The method of claim 1, wherein the dedicated channel comprises a
channel in a set of non-overlapping channels.
6. The method of claim 1, wherein the dedicated channel comprises a
common channel that is shared by multiple access points in the
wireless network.
7. The method of claim 1, wherein the access point comprises an
IEEE 802.11ai access point.
8. The method of claim 7, wherein the IEEE 802.11ai access point
comprises a dual-band access point.
9. The method of claim 7, wherein the IEEE 802.11ai access point
comprises a single-band access point.
10. The method of claim 1, wherein the wireless network comprises
an IEEE 802.11 wireless network.
11. The method of claim 1, wherein the broadcasted information
includes a list of nearby access points in the wireless
network.
12. The method of claim 1, further comprising establishing a
communication link with the particular identifiable access point
based on the broadcasted information.
13. The method of claim 12, wherein the establishing the
communication link with the particular identifiable access point
comprises: determining a primary operating channel of the
particular identifiable access point based on the broadcasted
information; transmitting an authentication frame to the particular
identifiable access point via the primary operating channel; and
receiving an acknowledgement frame from the particular identifiable
access point.
14. The method of claim 1, further comprising broadcasting, at the
first station, a probe request via the dedicated channel after a
particular time period has elapsed without detecting the
broadcasted information.
15. The method of claim 14, further comprising receiving a probe
response from the access point via the dedicated channel, wherein
the probe response includes the broadcasted information.
16. An apparatus comprising: a processor; and a memory coupled to
the processor, wherein the memory stores instructions that are
executable by the processor to perform operations comprising:
initiating, at a first station, a scan of a dedicated channel in a
wireless network to detect broadcasted information from an access
point in the wireless network; and obtaining identifying
information regarding a particular identifiable access point from
the broadcasted information, the broadcasted information including
a neighbor report, access point capability information, or a
combination thereof, and wherein the access point capability
information is carried in a fast initial link setup (FILS)
indication element according to an Institute of Electrical and
Electronics Engineers (IEEE) 802.11 ai protocol.
17. The apparatus of claim 16, wherein the neighbor report includes
a reduced neighbor report according to the IEEE 802.11ai
protocol.
18. The apparatus of claim 16, wherein the access point capability
information includes access point security information associated
with the particular identifiable access point and higher layer
capability information indicating higher layer capabilities of the
particular identifiable access point.
19. The apparatus of claim 16, wherein the neighbor report is
included in one of a beacon frame broadcasted from the access point
via the dedicated channel, a FILS discovery frame broadcasted from
the access point via the dedicated channel, or a probe response
from the access point.
20. The apparatus of claim 16, wherein the dedicated channel
comprises a channel in a set of non-overlapping channels.
21. A non-transitory computer-readable medium comprising
instructions that, when executed by a processor, cause the
processor to: initiate, at a first station, a scan of a dedicated
channel in a wireless network to detect broadcasted information
from an access point in the wireless network; and obtain
identifying information regarding a particular identifiable access
point from the broadcasted information, the broadcasted information
including a neighbor report, access point capability information,
or a combination thereof, and wherein the access point capability
information is carried in a fast initial link setup (FILS)
indication element according to an Institute of Electrical and
Electronics Engineers (IEEE) 802.11ai protocol.
22. The non-transitory computer-readable medium of claim 21,
wherein the neighbor report includes a reduced neighbor report
according to the IEEE 802.11ai protocol.
23. The non-transitory computer-readable medium of claim 21,
wherein the access point capability information includes access
point security information associated with the particular
identifiable access point and higher layer capability information
indicating higher layer capabilities of the particular identifiable
access point.
24. An apparatus comprising: means for scanning a dedicated channel
in a wireless network to detect broadcasted information from an
access point in the wireless network; and means for obtaining
identifying information regarding a particular identifiable access
point from the broadcasted information, the broadcasted information
including a neighbor report, access point capability information,
or a combination thereof, and wherein the access point capability
information is carried in a fast initial link setup (FILS)
indication element according to an Institute of Electrical and
Electronics Engineers (IEEE) 802.11ai protocol.
25. The apparatus of claim 24, wherein the neighbor report includes
a reduced neighbor report according to the IEEE 802.11ai
protocol.
26. The apparatus of claim 24, wherein the dedicated channel
comprises a channel in a set of non-overlapping channels.
27. The apparatus of claim 24, wherein the dedicated channel
comprises a common channel that is shared by multiple access points
in the wireless network.
Description
I. CLAIM OF PRIORITY
[0001] The present application claims priority from U.S.
Provisional Patent Application No. 61/972,851 entitled "DEDICATED
CHANNEL FOR FAST INITIAL LINK SETUP IN A WIRELESS NETWORK," filed
Mar. 31, 2014, the contents of which are incorporated by reference
in their entirety.
II. FIELD
[0002] The present disclosure is generally related to a dedicated
channel for fast initial link setup in a wireless network.
III. DESCRIPTION OF RELATED ART
[0003] Advances in technology have resulted in smaller and more
powerful computing devices. For example, there currently exist a
variety of portable personal computing devices, including wireless
computing devices, such as portable wireless telephones, personal
digital assistants (PDAs), and paging devices that are small,
lightweight, and easily carried by users. More specifically,
portable wireless telephones, such as cellular telephones and
Internet protocol (IP) telephones, can communicate voice and data
packets over wireless networks. Further, many such wireless
telephones include other types of devices that are incorporated
therein. For example, a wireless telephone can also include a
digital still camera, a digital video camera, a digital recorder,
and an audio file player. Also, such wireless telephones can
process executable instructions, including software applications,
such as a web browser application, that can be used to access the
Internet. As such, these wireless telephones can include
significant computing capabilities.
[0004] The Institute of Electrical and Electronics Engineers (IEEE)
has promulgated various industry specifications related to wireless
networking, many of which are designated with the "IEEE 802.11"
name. Typically, before a specification is drafted, a study group
and/or task group is formed to evaluate the interest and
feasibility of a particular wireless technology. For example, the
"ai" task group (referred to as TGai or IEEE 802.11ai) is related
to fast initial link setup (FILS). The TGai proposes broadcasting
neighborhood information using a reduced neighbor report (RNR)
information element (IE) that can be transmitted by access points
in a beacon, a probe response, or a FILS discovery frame. Once a
station (e.g., wireless telephone or other wireless device)
receives an RNR IE, the station may use information in the RNR IE
to establish a link with a "preferred" access point.
[0005] In order to receive nearby access point capability
information (via an RNR IE) from an 802.11ai access point in an
IEEE 802.11 network, a station entering the IEEE 802.11 network may
scan a randomly selected channel for the RNR IE or broadcast a
probe request via the randomly selected channel to receive a probe
response that includes the RNR IE. However, if an 802.11ai access
point is not operating on the randomly selected channel, the
station may have to scan (or broadcast another probe request on)
another channel to receive the RNR IE. Scanning multiple channels
for an RNR IE may increase the amount of time for establishing the
link with the preferred access point. For example, dual band access
points in an IEEE 802.11 network may operate in a 2.4 Giga-Hertz
(GHz) frequency band and a 5 GHz frequency band. The 2.4 GHz
frequency band may include 11 channels, and the 5 GHz frequency
band may include 12 channels. Thus, in some instances, the station
may scan up to 23 channels prior to receiving an RNR IE from an
802.11ai access point in the IEEE 802.11 network. Scanning and/or
probing multiple channels increases an initial link setup time.
IV. SUMMARY
[0006] The present disclosure presents techniques and protocols
that enable a mobile device to scan a dedicated channel to obtain a
neighbor report (e.g., a reduced neighbor report) from an access
point, such as an Institute of Electrical and Electronics Engineers
(IEEE) 802.11ai compliant access point. For example, the mobile
device may scan a fast initial setup link (FILS) channel for a FILS
frame (e.g., a beacon frame, a FILS discovery frame, and/or a probe
response frame) that includes a reduced neighbor report transmitted
by an IEEE 802.11ai access point.
[0007] To illustrate, upon entering an IEEE 802.11 wireless
network, a mobile device may scan (e.g., tune to) a defined FILS
channel to detect the presence of an IEEE 802.11ai access point.
For example, the FILS channel may be a predetermined channel in
which IEEE 802.11ai access points transmit (e.g., broadcast)
reduced neighbor reports (e.g., a report that includes a list of
nearby access points). The reduced neighbor reports may be
transmitted via beacons, probe response frames and/or FILS
discovery frames. In response to detecting a reduced neighbor
report, the mobile station may obtain information about a
"preferred" access point. The preferred access point may be an
access point provided by a wireless service provider of the mobile
device or an access point of a wireless network that is preferred
by the user of the mobile device. The mobile device may obtain
information regarding the operating class of the preferred access
point, the primary operating channel of the preferred access point,
the basic service set identification (BSSID) of the preferred
access point, the target beacon transmission time (TBTT) of the
preferred access point, etc. The mobile device may use the obtained
information to perform an authentication routine (or handshake)
with the preferred access point (e.g., to establish a communication
link with the preferred access point). In addition, or in the
alternative, the mobile device may broadcast a probe request on the
FILS channel after scanning the FILS channel for a particular
amount of time (e.g., approximately 5 milliseconds (ms)) without
detecting a frame (e.g., beacon, FILS discovery or broadcast probe
response frame) containing a reduced neighbor report. An IEEE
802.11ai access point may transmit a probe response that includes a
reduced neighbor report to the mobile device in response to
detecting the probe request on the FILS channel.
[0008] According to techniques and protocols of the present
disclosure, at least one IEEE 802.11ai access point may maintain a
"light" association with the FILS channel to receive probe
requests, generate FILS frames that include reduced neighbor
reports, and/or transmit the FILS frames to the mobile device via
the FILS channel. To illustrate, IEEE 802.11ai access points may be
dual-band (e.g., dual radio) access points having primary radios
configured to perform standard access point operations and a
secondary radio (e.g., a FILS radio) that is "lightly loaded" and
configured to provide information (e.g., reduced neighbor reports)
to IEEE 802.11ai stations (e.g., mobile devices) accessing the IEEE
802.11 network.
[0009] Alternatively, at least one IEEE 802.11ai access point may
tune out a primary operating channel if the FILS channel is
different from the primary operating channel to receive the probe
request, generate a probe response, and transmit the probe response
to the mobile device via the FILS channel. To illustrate, IEEE
802.11ai access points may be single-band access points that issue
self clear-to-send (CTS) packets to block traffic on the primary
operating channel. The single-band access points may tune to the
FILS channel to receive the probe requests, generate FILS frames
that include reduced neighbor reports, and/or transmit the FILS
frames to the mobile device via the FILS channel.
[0010] The IEEE 802.11ai access points may utilize a coordination
scheme to reduce traffic on the FILS channel. For example, prior to
transmitting (e.g., broadcasting) a FILS frame, an IEEE 802.11ai
access point may "listen on" the FILS channel for a relatively
short amount of time (e.g., 5 ms) to detect FILS frames from other
access points. The IEEE 802.11ai access point may suppress
transmission of the FILS frame if at least one of two criteria has
been satisfied. First, the IEEE 802.11ai access point may suppress
transmission of the FILS frame if at least one other access point
has broadcasted a FILS frame at a short range. For example, if the
IEEE 802.11ai access point detects a FILS frame on the FILS channel
having a relatively high received signal strength indicator (RSSI),
the IEEE 802.11ai access point may suppress transmission of the
FILS frame because the coverage area of the other access point is
most likely similar to the coverage area of the IEEE 802.11ai
access point. Secondly, the IEEE 802.11ai access point may suppress
transmission of the FILS frame if three other access points have
broadcasted a FILS frame at a medium range (e.g., mid-range RSSIs)
on the FILS channel. Three access points broadcasting FILS frames
at medium range may imply that the IEEE 802.11ai access point is
approximately within a triangle formed by the three access points
such that the coverage area of the three access points,
collectively, is similar to the coverage area of the IEEE 802.11ai
access point. However, if either criteria is satisfied and the IEEE
802.11ai access point determines that the reduced neighbor reports
in the FILS frames broadcasted on the FILS channel do not list all
of the neighboring access points in the reduced neighbor report of
the IEEE 802.11ai access point, the IEEE 802.11 access point may
override transmission suppression and broadcast the FILS frame on
the FILS channel.
[0011] According to one example of the techniques described herein,
a method includes generating identifying information at an access
point and broadcasting the identifying information via a dedicated
channel in a wireless network. The identifying information includes
a neighbor report (e.g., a reduced neighbor report), access point
capability information (e.g., access point security information
associated with the access point and higher layer capability
information indicating higher layer capabilities of the access
point), or a combination thereof. The access point capability
information is carried in a fast initial link setup (FILS)
indication element according to an Institute of Electrical and
Electronics Engineers (IEEE) 802.11ai protocol.
[0012] According to another example of the techniques described
herein, an apparatus includes a processor and a memory coupled to
the processor. The memory stores instructions that are executable
by the processor to perform operations. The operations include
generating identifying information at an access point and
broadcasting the identifying information via a dedicated channel in
a wireless network. The identifying information includes a neighbor
report (e.g., a reduced neighbor report), access point capability
information (e.g., access point security information associated
with the access point and higher layer capability information
indicating higher layer capabilities of the access point), or a
combination thereof. The access point capability information is
carried in a fast initial link setup (FILS) indication element
according to an Institute of Electrical and Electronics Engineers
(IEEE) 802.11ai protocol.
[0013] According to another example of the techniques described
herein, a non-transitory computer-readable medium includes
instructions that, when executed by a processor, cause the
processor to generate identifying information at an access point
and initiate a broadcast of the identifying information via a
dedicated channel in a wireless network. The identifying
information includes a neighbor report (e.g., a reduced neighbor
report), access point capability information (e.g., access point
security information associated with the access point and higher
layer capability information indicating higher layer capabilities
of the access point), or a combination thereof. The access point
capability information is carried in a fast initial link setup
(FILS) indication element according to an Institute of Electrical
and Electronics Engineers (IEEE) 802.11ai protocol.
[0014] According to another example of the techniques described
herein, an apparatus includes means for determining a signal
strength of at least one broadcasted neighbor report on a dedicated
channel in a wireless network and means for broadcasting
identifying information via the dedicated channel in response to a
determination that the signal strength fails to satisfy a
threshold. The identifying information includes a neighbor report
(e.g., a reduced neighbor report), access point capability
information (e.g., access point security information associated
with the access point and higher layer capability information
indicating higher layer capabilities of the access point), or a
combination thereof. The access point capability information is
carried in a fast initial link setup (FILS) indication element
according to an Institute of Electrical and Electronics Engineers
(IEEE) 802.11ai protocol.
[0015] According to another example of the techniques described
herein, a method includes scanning, at a first station, a dedicated
channel in a wireless network to detect broadcasted information
from an access point in the wireless network. The method also
includes obtaining identifying information regarding a particular
identifiable access point from the broadcasted information. The
broadcasted information includes a neighbor report (e.g., a reduced
neighbor report), access point capability information (e.g., access
point security information associated with the particular
identifiable access point and higher layer capability information
indicating higher layer capabilities of the particular identifiable
access point), or a combination thereof. The access point
capability information is carried in a fast initial link setup
(FILS) indication element according to an Institute of Electrical
and Electronics Engineers (IEEE) 802.11ai protocol.
[0016] According to another example of the techniques described
herein, an apparatus includes a processor and a memory coupled to
the processor. The memory stores instructions that are executable
by the processor to perform operations. The operations include
scanning, at a first station, a dedicated channel in a wireless
network to detect broadcasted information from an access point in
the wireless network. The operations also include obtaining
identifying information regarding a particular identifiable access
point from the broadcasted information. The broadcasted information
includes a neighbor report (e.g., a reduced neighbor report),
access point capability information (e.g., access point security
information associated with the particular identifiable access
point and higher layer capability information indicating higher
layer capabilities of the particular identifiable access point), or
a combination thereof. The access point capability information is
carried in a fast initial link setup (FILS) indication element
according to an Institute of Electrical and Electronics Engineers
(IEEE) 802.11ai protocol.
[0017] According to another example of the techniques described
herein, a non-transitory computer-readable medium includes
instructions that, when executed by a processor, cause the
processor to initiate, at a first station, a scan of a dedicated
channel in a wireless network to detect broadcasted information
from an access point in the wireless network. The instructions are
also executable to cause the processor to obtain identifying
information regarding a particular identifiable access point from
the broadcasted information. The broadcasted information includes a
neighbor report (e.g., a reduced neighbor report), access point
capability information (e.g., access point security information
associated with the particular identifiable access point and higher
layer capability information indicating higher layer capabilities
of the particular identifiable access point), or a combination
thereof. The access point capability information is carried in a
fast initial link setup (FILS) indication element according to an
Institute of Electrical and Electronics Engineers (IEEE) 802.11ai
protocol.
[0018] According to another example of the techniques described
herein, an apparatus includes means for scanning a dedicated
channel in a wireless network to detect broadcasted information
from an access point in the wireless network. The apparatus also
includes means for obtaining identifying information regarding a
particular identifiable access point from the broadcasted
information. The broadcasted information includes a neighbor report
(e.g., a reduced neighbor report), access point capability
information (e.g., access point security information associated
with the particular identifiable access point and higher layer
capability information indicating higher layer capabilities of the
particular identifiable access point), or a combination thereof.
The access point capability information is carried in a fast
initial link setup (FILS) indication element according to an
Institute of Electrical and Electronics Engineers (IEEE) 802.11ai
protocol.
[0019] One advantage provided by at least one of the disclosed
aspects is a reduction in initial scan for a station (e.g., a
mobile device) to find a preferred access point of the station. For
example, the station may obtain information (e.g., a reduced
neighbor report) about the preferred access point by scanning
and/or probing a dedicated channel as opposed to selectively
scanning/probing random channels that may or may not have
information about the preferred access point. Other aspects,
advantages, and features of the present disclosure will become
apparent after review of the entire application, including the
following sections: Brief Description of the Drawings, Detailed
Description, and the Claims.
V. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a diagram of a system that is operable to enable
fast initial link setup via a dedicated channel;
[0021] FIG. 2 is a diagram of another system that is operable to
enable fast initial link setup via a dedicated channel;
[0022] FIG. 3 is a flow diagram of an illustrative method for
enabling fast initial link setup via a dedicated channel;
[0023] FIG. 4 is a flow diagram of another illustrative method for
enabling fast initial setup via dedicated channel;
[0024] FIG. 5 is a flow diagram of another illustrative method for
enabling fast initial link setup via a dedicated channel;
[0025] FIG. 6 is a flow diagram of another illustrative method for
enabling fast initial setup via dedicated channel; and
[0026] FIG. 7 is a diagram of a wireless device that is operable to
support various techniques of one or more methods, systems,
apparatuses, and/or computer-readable media disclosed herein.
VI. DETAILED DESCRIPTION
[0027] Particular techniques of the present disclosure are
described with reference to the drawings. In the description,
common features are designated by common reference numbers
throughout the drawings.
[0028] Institute of Electrical and Electronics Engineers (IEEE)
802.11 task group (TG) ai (hereinafter "TGai") is a task group
involved in the study of fast initial link setup (FILS). In
accordance with TGai submission(s), a neighbor report, such as a
reduced neighbor report (RNR) information element (IE) may be
included in a beacon response, a probe response, or a FILS
discovery frame. For example, an access point may provide an RNR IE
to a mobile device (e.g., a mobile station (STA)) that is not
associated with the access point. The RNR IE may identify or
reference one or more access points neighboring (e.g., surrounding)
the access point and may aid the unassociated mobile device to find
a "preferred" access point (e.g., an access point provided by a
particular wireless service provider). For each access point
identified in an RNR IE, the RNR IE may include information that
identifies a channel (e.g., an operating channel) of the access
point and a target beacon transmission time (TBTT) for the access
point. The TBTT may be represented as an offset from a time
associated with the RNR IE. Thus, a mobile device may be able to
identify a particular (e.g., preferred) access point based on the
information in the RNR IE.
[0029] Moreover, the mobile device may determine the operating
channel and target beacon transmission time of the access point
from the RNR IE, and the mobile device may therefore be able to
receive a beacon from the access point, and initiate an
authentication/association process with the access point without
having to scan multiple channels and without having to scan for an
extended period of time. The mobile device may also be able to
gather additional capability information regarding the access point
via FILS field(s) included in the beacon. The mobile device may use
the operating channel information in the RNR IE to send a probe
request to the particular (e.g., preferred) access point to solicit
a probe response. The probe response may include additional
capability information (e.g., in one or more FILS fields) regarding
the access point. A FILS Indication IE (included in a beacon, a
FILS discovery frame, and/or a probe response frame) may also
include additional information regarding access points, such as a
subnet identifier (ID), security information, etc. Accordingly, the
RNR IE and the FILS Indication IE may enable the mobile device to
quickly select an available access point to associate with while
reducing a scan time and/or a probing overhead. The RNR IE may
include a service set identifier (SSID). For example, a SSID may be
more advantageous than a basic service set identifier (BSSID) to
stations that have never associated with an access point
previously. For example, the SSID may be more useful because
different access points in the same extended service set
identification (ESSID) may have the same SSID.
[0030] The disclosed systems, devices, and methods may enable a
mobile device to receive an RNR IE via a dedicated channel to
reduce a scan time and/or probing overhead. For example, each
access point in a wireless network (e.g., an IEEE 802.11 wireless
network) may transmit (e.g., broadcast) beacons, probe responses,
and FILS discovery frames on the dedicated channel. A station
within the wireless network may tune to the dedicated channel to
receive an RNR IE from a beacon, probe response, or FILS discovery
frame. Based on the received RNR IE, the station may find its
preferred access point in the wireless network.
[0031] Referring to FIG. 1, a system 100 that is operable to enable
fast initial link setup via a dedicated channel is shown. The
system 100 includes a first access point (AP) 110, designated
AP.sub.A in FIG. 1, a mobile device 120 (alternately referred to
herein as a station (STA) and designated STA.sub.A in FIG. 1), and
a second access point 130 (designated AP.sub.B). It should be noted
that additional (or fewer) access points may be present in the
system 100. For example, as described below, the system 100 also
includes a home access point 160. Additionally, it should be noted
that although FIG. 1 depicts a single mobile device 120, any number
of mobile devices may be present in the system 100. The first
access point 110, the mobile device 120, and the second access
point 130 may operate in compliance with one or more IEEE 802.11
standards, such as 802.11ai, as an illustrative, non-limiting
example.
[0032] The mobile device 120 may be an electronic device that is
operable to send and receive data via a wireless network. For
example, the mobile device 120 may be a wireless phone, a personal
digital assistant (PDA), a portable computing device, a tablet
computing device, a portable media player, or a combination
thereof. The mobile device 120 may be configured to perform an
authentication routine, such as a handshake and key exchange
routine, with one or more access points. For example, the mobile
device 120 may perform an authentication routine with the first
access point 110 to establish an authenticated session (e.g., an
associated session) with the first access point 110. For example,
the authenticated session may enable secure (e.g., encrypted)
communication between the mobile device 120 and the access point
110. When the mobile device 120 communicates with the first access
point 110 during an associated session, the mobile device 120 is
considered to be configured in an associated state with the first
access point 110. When the mobile device 120 is not in an
associated session with a particular access point, the mobile
device is considered to be configured in an unassociated state
(e.g., a pre-associated state) with the particular access point.
When the mobile device 120 is in the unassociated state with a
particular access point, the mobile device 120 and the particular
access point may communicate using unsecured messages, such as
probe response messages, beacons, FILS discovery frames, or control
messages.
[0033] Each of the access points 110, 130 may be a node of a
wireless network. For example, each of the access points 110, 130
may be an IEEE 802.11 access point that supports (e.g., manages) a
corresponding wireless data network. For example, the first access
point 110 may support a first network 112 and the second access
point 130 may support a second network 132. Each of the access
points 110, 130 may include (e.g., store) a corresponding neighbor
report. A particular neighbor report of a particular access point
may identify neighboring (e.g., surrounding) access points in
relation to the particular access point. For example, the first
access point 110 may include (e.g., store) a first neighbor report
114 that identifies neighboring access points of the first access
point 110, and the second access point 130 may include (e.g.,
store) a second neighbor report 134 that identifies neighboring
access points of the second access point 130.
[0034] The first access point 110 may generate first identifying
information (e.g., the first neighbor report 114, first access
point capability information, or a combination thereof) and the
second access point 130 may generate second identifying information
(e.g., the second neighbor report 134, second access point
capability information, or a combination thereof). Thus, the
techniques described herein support generating identifying
information at an access point. The identifying information
includes a neighbor report, access point capability information, or
a combination thereof. In one example, the neighbor report includes
a reduced neighbor report according to the IEEE 802.11ai protocol.
In one example, the access point capability information includes
access point security information associated with the access point
and higher layer capability information indicating higher layer
capabilities of the access point. To illustrate, the access point
security information may include information associated with "built
in" access point encryption schemes (e.g., Wi-Fi Protected Access
(WPA), Wi-Fi Protected Access II (WPA2)). The higher layer
capability information may indicate an access point's ability to
process higher protocol layers in IEEE 802.11 data packets.
[0035] For each neighboring access point identified or referenced
in a neighbor report, such as the first neighbor report 114 or the
second neighbor report 134, the neighbor report may also identify
an operating channel of the neighboring access point, a media
access control (MAC) address of the neighboring access point, a
signal strength (e.g., a received signal strength indication
(RSSI)) of the neighboring access point, one or more other
parameters related to the neighboring access point, or a
combination thereof, as illustrative, non-limiting examples. For
example, the first neighbor report 114 and/or the second neighbor
report 134 may include or correspond to a reduced neighbor report
(RNR) compliant with 802.11ai, such as an RNR that includes one or
more information elements (IEs) defined by the IEEE 802.11ai
standard. The first neighbor report 114 and/or the second neighbor
report 134 may include information regarding neighboring access
points. For example, the neighbor reports 114, 134 may include
information regarding operating classes of neighboring access
points, primary operating channels of neighboring access points,
target beacon transmission times (TBTTs) of neighboring access
points, and basic service set identifications (BBSIDs) of
neighboring access points.
[0036] During operation, the mobile device 120 may enter within
transmission range of the first network 112 of the first access
point 110 and/or the second network 132 of the second access point
130. The first access point 110 may be configured to broadcast
identifying information (e.g., the first neighbor report 114 and/or
first access point capability information) to stations (e.g., the
mobile device 120) and other access points within transmission
range of the first network 112 via a dedicated channel 150. Thus,
the techniques described herein support broadcasting the
identifying information via a dedicated channel in a wireless
network. The first access point capability information may include
first access point security information associated with the first
access point 110 and higher layer capability information indicating
higher layer capabilities of the first access point 110. In one
example, the access point capability information is carried in a
fast initial link setup (FILS) indication element according to an
Institute of Electrical and Electronics (IEEE) 802.11ai
protocol.
[0037] The dedicated channel 150 is a common channel shared by
multiple access points to broadcast RNRs. Although one dedicated
channel 150 is depicted in FIG. 1, the dedicated channel 150 may be
a particular channel in a list (e.g., set) of dedicated channels.
As a non-limiting example, the list of dedicated channels may
include three non-overlapping channels in a 2.4 GHz frequency band.
Thus, the dedicated channel 150 comprises a particular channel in a
set of non-overlapping channels. The first access point 110 may
broadcast a beacon frame that includes the identifying information
(e.g., the first neighbor report 114 and/or the first access point
capability information) via the dedicated channel 150. For example,
the first access point 110 may broadcast a beacon frame
approximately once every 100 milliseconds (ms). Beacon
transmissions on the dedicated channel 150 may be synchronized to a
global time source to reduce power drain during scanning operations
at the mobile device 120, as described below. For example, beacon
transmissions on the dedicated channel 150 may be synchronized to a
global positioning system (GPS) or to cellular time. Alternatively,
or in addition, the first access point 110 may broadcast a FILS
discovery frame that includes the information (e.g., the first
neighbor report 114 and/or the first access point capability
information) via the dedicated channel 150. For example, the first
access point 110 may broadcast a FILS discovery frame approximately
once every 20 ms. As explained below, the first access point 110
may also broadcast a probe response frame that includes the first
neighbor report 114 in response to receiving a probe request 124
from the mobile device 120. The first access point capability
information may be carried in a FILS Indication element according
to an IEEE 802.11ai protocol.
[0038] In a similar manner, the second access point 130 may be
configured to broadcast information (e.g., the second neighbor
report 134 and/or second access point capability information) to
stations (e.g., the mobile device 120) and other access points
within transmission range of the second network 132 via the
dedicated channel 150. The second access point capability
information may include security information associated with the
second access point 130 and information indicating higher layer
capabilities of the second access point 130). The second access
point 130 may broadcast a beacon frame (e.g., approximately once
every 100 ms) that includes the information (e.g., the second
neighbor report 134 and/or the second access point capability
information) via the dedicated channel 150. Alternatively, or in
addition, the second access point 130 may broadcast a FILS
discovery frame (e.g., approximately once every 20 ms) that
includes the second neighbor report 134 via the dedicated channel
150. As explained below, the second access point 130 may also
broadcast a probe response frame that includes the second neighbor
report 134 in response to receiving the probe request 124 from the
mobile device 120. The second access point capability information
may be carried in a FILS Indication element according to an IEEE
802.11ai protocol.
[0039] FILS discovery frames transmitted from the access points
110, 130 may enable relatively quick access point discovery. For
example, FILS discovery frames may include a service set
identification (SSID) number, an access point configuration change
count, the transmitting access point's next TBTT, a neighboring
access point's next TBTT, an RNR (e.g., the first neighbor report
114 and/or the second neighbor report 134), access point capability
(e.g., operating channel bandwidth, supported data rates, etc.),
security/internet protocol (IP) address type capabilities, etc.
Transmitting FILS discovery frames on the dedicated channel 150 may
increase data throughput on primary operating channels of the
access points 110, 130. For example, transmitting FILS discovery
frames on the dedicated channel 150 (as opposed to the primary
operating channels) may enable additional data frames to be
transmitted on the primary operating channels.
[0040] The FILS discovery frames transmitted on the dedicated
channel 150 may also include information corresponding to the
transmitting access point's primary operating channel. The FILS
discovery frames may include a subset of information in a standard
802.11ai FILS discovery frame to enable quick access point
discovery. For example, in some scenarios, the access point
capability, SSIDs, and the access point configuration change count
may be omitted from the FILS discovery frames such that the mobile
device 120 may process information at a faster rate. Additionally,
the FILS discovery frames may be transmitted at a relatively high
data rate to reduce congestion (e.g., "air occupancy") on the
dedicated channel 150.
[0041] The access points 110, 130 may be IEEE 802.11ai access
points. For example, the neighbor reports 114, 134 generated by the
access points 110, 130 may be in compliance (e.g., include
information in compliance) with the IEEE 802.11ai standard. The
access points 110, 130 may be dual-band access points or
single-band access points. A dual-band access point may have a
first operating frequency channel in a first frequency band (e.g.,
a 5 Giga-Hertz (GHz) frequency band) and a second operating
frequency channel in a second frequency band (e.g., a 2.4 GHz
frequency band). A single-band access point may have an operating
frequency channel in the second frequency band. The second
frequency band may include 11 channels, and the first frequency
band may include 12 channels. Thus, the dedicated channel 150 may
be a channel within the second frequency band such that single-band
access points and dual-band access points may broadcast on the
dedicated channel 150. The dedicated channel 150 may be the sixth
channel (e.g., channel 6) of the second frequency band. For
example, the sixth channel of the second frequency band may be a
FILS common channel.
[0042] Thus, according to the techniques described herein, the
access point comprises an IEEE 802.11ai access point, and the
wireless network comprises an IEEE 802.11 wireless network. In one
example, the IEEE 802.11ai access point comprises a dual-band
access point. In another example, the IEEE 802.11ai access point
comprises a single-band access point.
[0043] The mobile device 120 may be configured to scan the
dedicated channel 150 to detect an RNR from the first access point
110 or to detect an RNR from the second access point 130. For
example, upon entering a transmission range of the first network
112 and/or the second network 132, the mobile device 120 may scan
the dedicated channel 150 (e.g., channel 6) to detect beacons or
FILS discovery frames that are broadcasted on the dedicated channel
150 via the access points 110, 130. The mobile device 120 may scan
the dedicated channel 150 at particular times that are synchronized
to a global time source to reduce power drain associated with
scanning operations. For example, if the access points 110, 130
broadcast beacons according to the global time source, the mobile
device 120 may reduce an effective amount of scans on the dedicated
channel 150 for beacons by synchronizing scanning operations with
the global time source. Reducing the effective amount of scans may
conserve power at the mobile device 120. Beacons and FILS discovery
frames broadcasted from the first access point 110 may include the
first neighbor report 114, and beacons and FILS discovery frames
broadcasted from the second access point 130 may include the second
neighbor report 134.
[0044] When the mobile device 120 detects a beacon and/or a FILS
discovery frame on the dedicated channel 150, the mobile device may
obtain information about a "preferred" access point from the
neighbor report 114, 134 in the detected beacon and/or FILS
discovery frame. As a non-limiting example, the preferred access
point may be an access point provided by a particular wireless
service provider of the mobile device 120 or an access point for a
particular wireless network associated with the mobile device 120.
According to one implementation, the preferred access point is
defined by the mobile device 120. According to another
implementation, the preferred access point is defined by a service
provider of the mobile device 120. To illustrate, in FIG. 1, a home
access point 160 may be a preferred access point of the mobile
device 120. The home access point 160 may support a "home" network
162 of the mobile device 120, and the first network 112 may be
another wireless network (e.g., a wireless network of a coffee
shop). Thus, the mobile device 120 may attempt to obtain
information about the home access point 160 to establish a
connection with the home network 162 of the mobile device 120
(e.g., perform an authentication routine or handshake with the home
access point 160). The home access point 160 may operate on the
dedicated channel 150 (e.g., broadcast neighbor reports to stations
(e.g., the mobile device 120) and other access points within
transmission range of the home network 162 via a dedicated channel
150) and a primary operating channel 164. The home access point 160
may not operate on the dedicated channel 150 and may maintain all
operations on the primary operating channel 164.
[0045] During scanning operations, if the mobile device 120 detects
the first neighbor report 114 broadcasted from the first access
point 110, the mobile device 120 may obtain information about the
second access point 130 from the first neighbor report 114. For
example, the mobile device 120 may obtain an operating class of the
second access point 130, a primary operating channel of the second
access point 130, a TBTT of the second access point 130, and/or a
basic service set identification (BSSID) of the second access point
130 from the first neighbor report 114. Based on the obtained
information, the mobile device 120 may establish a communication
link (e.g., initiate an authentication/association process) with
the second access point 130.
[0046] After scanning the dedicated channel 150 for a particular
time period, the mobile device 120 may generate and transmit (e.g.,
broadcast) the probe request 124 via the dedicated channel 150 if
the mobile device has not detected an RNR from at least one of the
access points 110, 130. The probe request 124 may indicate to the
access points 110, 130 that the mobile device 120 needs to obtain
information (e.g., an RNR) to establish a connection with a
particular access point.
[0047] Upon receiving the probe request 124, each access point 110,
130 may respond to the probe request 124 (e.g., generate and
broadcast a probe response) via the dedicated channel 150. To
illustrate, each access point 110, 130 may respond to the probe
request 124 (e.g., transmit a probe response that includes an RNR)
by operating on the dedicated channel 150 (e.g., channel 6).
Alternatively, each access point 110, 130 may maintain a "light"
network on the dedicated channel 150. For example, each access
point 110, 130 may operate on the first channel (channel 1) or the
eleventh channel (channel 11) of the 2.4 GHz frequency band in a 40
Mega-Hertz (MHz) mode to maintain a light network (e.g., a light
connection) on the dedicated channel 150 to respond to the probe
request 124.
[0048] In response to broadcasting the probe request 124, the
mobile device 120 may receive a probe response from at least one of
the access points 110, 130. For example, the mobile device 120 may
receive a probe response including the first neighbor report 114
from the first access point 110, a probe response including the
second neighbor report 134 from the second access point 130, or a
combination thereof. Based on the obtained information in the
neighbor report(s) 114, 134, the mobile device 120 may establish a
communication link (e.g., perform an authentication routine or
handshake) with the home access point 160. For example, the mobile
device 120 may determine the primary operating channel 164 of the
home access point 160 based on the obtained information in the
neighbor report(s) 114, 134, transmit an authentication frame to
the home access point 160 via the primary operating channel 164,
receive an acknowledgment frame from the home access point 160 via
the primary operating channel 164, etc. The mobile device 120 may
select the home access point 160 from a plurality of access points.
The preferred access point of the mobile device 120 may correspond
to an access point that transmits an RNR (or probe response) that
is detected by the mobile device 120.
[0049] The initial link setup time to establish a communication
link between the mobile device 120 and a preferred access point may
be reduced by utilizing the dedicated channel 150 to obtain RNRs.
For example, the mobile device 120 may scan and/or probe the
dedicated channel 150 to receive RNRs from the access points 110,
130 as opposed to scanning and/or probing multiple channels before
detecting an 802.11ai access point. Thus, utilizing the dedicated
channel 150 for RNR detection reduces the likelihood of the mobile
device 120 scanning a channel that is not actively being used by an
802.11ai access point.
[0050] Referring to FIG. 2, another system 200 that is operable to
enable fast initial link setup via a dedicated channel is shown.
The system 200 includes the first access point 110, the mobile
device 120, the second access point 130, a third access point
(designated AP.sub.C) 260, a fourth access point (designated
AP.sub.D) 270, a fifth access point (designated AP.sub.E) 280, and
a sixth access point (designated AP.sub.F) 290. It should be noted
that although FIG. 2 depicts six access points 110, 130, 260, 270,
280, 290, any number of access points may be present in the system
200. Additionally, it should be noted that although FIG. 2 depicts
a single mobile device 120, any number of mobile devices may be
present in the system 200. Each of the access points 110, 130, 260,
270, 280, 290 and the mobile device 120 may operate in compliance
with one or more IEEE 802.11 standards, such as 802.11ai.
[0051] Each of the access points 110, 130, 260, 270, 280, 290 may
be a node of a wireless network. For example, each of the access
points 110, 130, 260, 270, 280, 290 may be an IEEE 802.11 access
point that is associated with a corresponding network (e.g., a
wireless network). For example, the first access point 110 may
support the first network 112, the second access point 130 may
support the second network 132, the third access point 260 may
support a third network 262, the fourth access point 270 may
support a fourth network 272, the fifth access point 280 may
support a fifth network 282, and the sixth access point 290 may
support a sixth network 292. Each of the access points 110, 130,
260, 270, 280, 290 may include (e.g., store) a corresponding
neighbor report. Each neighbor report may include, or correspond
to, an RNR. Each access point's neighbor report may identify one or
more neighboring access points and may be included in one or more
beacon frames, one or more neighbor reports, or a combination
thereof.
[0052] During operation, each access point 110, 130, 260, 270, 280,
290 may determine whether to suppress the broadcast of a FILS frame
based on the received signal strength of at least one neighboring
access point's FILS frame on the dedicated channel 150. As used
herein, a FILS frame may correspond to any broadcast from an access
point that includes an RNR or any other information used to
facilitate an initial link setup between the mobile station 120 and
an access point. For example, a FILS frame may include a beacon
frame, a FILS discovery frame, a probe response, etc. Each access
point 110, 130, 260, 270, 280, 290 may scan the dedicated channel
to detect FILS frames from neighboring access points and measure
the received signal strength of the detected FILS frames. If the
received signal strength of at least one neighboring point's FILS
frame on the dedicated channel 150 satisfies a threshold, an access
point may suppress transmission of a FILS broadcast to reduce
traffic on the dedicated channel 150.
[0053] As an illustrative example, prior to broadcasting a FILS
frame (e.g., the first neighbor report 114), the first access point
110 may scan (e.g., "listen in on") the dedicated channel 150 for a
particular time period to detect one or more broadcasted FILS
frames from one or more access points. The first access point 110
may scan the dedicated channel 150 for approximately 5 ms to detect
one or more RNRs from one or more access points. Based on the scan,
the first access point 110 may determine whether an access point
within a close proximity has broadcasted a FILS frame on the
dedicated channel 150. In response to a determination that an
access point within a relatively close proximity has broadcasted a
FILS frame on the dedicated channel 150, the first access point 110
may suppress broadcast transmission of the first neighbor report
114. For example, the third access point 260 may broadcast a first
FILS frame via the dedicated channel 150, and the first access
point 110 may detect the first FILS frame during scanning
operations. The first access point 110 may measure a first received
signal strength of the first FILS frame. For example, the first
access point 110 may determine a proximity of the third access
point 260 based on a received signal strength indicator (RSSI) 250
associated with the first FILS frame. A relatively high RSSI 250
may indicate that the third access point 260 is in close proximity
to the first access point 110, and a relatively low RSSI 250 may
indicate that the third access point 260 is not in close proximity
to the first access point 110.
[0054] In response to a determination that the first received
signal strength of the first FILS frame satisfies a first threshold
(e.g., is greater than or equal to a first threshold signal
strength or has a relatively high RSSI 250), the first access point
110 may suppress the broadcast of the first neighbor report 114 via
the dedicated channel 150. For example, the first access point 110
may determine that the third access point's 260 coverage area is
substantially similar to the coverage area of the first access
point 110 when the first received signal strength satisfies the
first threshold. However, if the first access point 110 determines
that the first FILS frame does not reference each of the
neighboring access points in the first neighbor report 114, the
first access point 110 may broadcast the first neighbor report 114
via the dedicated channel 150.
[0055] The first threshold may correspond to a suppression range
(e.g., a maximum range between the first access point 110 and the
third access point 260 that results in the first access point 110
suppressing the broadcast of the first neighbor report 114). For
example, the suppression range increases as the first threshold
decreases. The suppression range may be preprogrammed into each
access point 110, 130, 260, 270, 280, 290 according to an industry
standard, such as an IEEE 802.11 standard. A short suppression
range may improve reliability by increasing the number of
broadcasters. However, a short suppression range may also increase
overhead (e.g., generate a relatively large amount of redundant
traffic on the dedicated channel 150) and increase broadcast
contention.
[0056] Additionally, the first access point 110 may determine
whether three or more access points within a relatively close
proximity have broadcast a FILS frame during scanning operations.
For example, during a scanning operation of the first access point
110, the third access point 260 may broadcast the first FILS frame
via the dedicated channel 150, the fourth access point 270 may
broadcast a second FILS frame via the dedicated channel 150, and
the fifth access point 280 may broadcast a third FILS frame via the
dedicated channel 150. The first access point 110 may detect the
first FILS frame, the second FILS frame, and the third FILS frame
on the dedicated channel 150. In addition, the first access point
110 may measure the first received signal strength of the first
FILS frame, the second received signal strength of the second FILS
frame, and the third received signal strength of the third FILS
frame. The first access point 110 may determine the proximity of
each access point 260-280 based on RSSIs 250 associated with the
received FILS frames.
[0057] In response to a determination that the each received signal
strength satisfies a second threshold (e.g., is greater than or
equal to a second threshold signal strength or has a mid-range RSSI
250), the first access point 110 may suppress the broadcast of the
first neighbor report 114. For example, the first access point 110
may determine that the coverage areas of the third, fourth, and
fifth access points 260-280, collectively, have a relatively high
probability of covering the stations in the coverage area of the
first access point 110 when each received signal strength satisfies
the second threshold. The first access point 110 may be within a
triangle formed by the third, fourth, and fifth access points
260-280. Thus, any stations in the coverage area of the first
access point 110 would most likely receive at least one of the
first FILS frame from the third access point 260, the second FILS
frame from the fourth access point 270, or the third FILS frame
from the fifth access point 280. For example, the mobile device 120
may have a high probability of receiving at least one of the first
FILS frame, the second FILS frame, or the third FILS frame.
However, if the first access point 110 determines that the neighbor
reports in the FILS frames from the access points 260-280 do not
list each access point in the first neighbor report 114, the first
access point 110 may broadcast the first neighbor report 114 via
the dedicated channel 150.
[0058] The first access point 110 may reduce overhead (e.g.,
congestion) on the dedicated channel 150 by suppressing the
broadcast of the first neighbor report 114 when the received signal
strength of one or more neighboring access point's FILS frames on
the dedicated channel 150 satisfies a threshold. Implementing the
coordination scheme described above may enable FILS frames to be
spread in time and coverage area. It will be appreciated that the
coordination scheme does not require any messaging between access
points because the access points may scan the dedicated channel 150
(e.g., the common channel shared by each access point) to determine
received signal strengths of FILS frames.
[0059] Referring to FIG. 3, a method 300 for enabling fast initial
link setup via a dedicated channel is described. The method 300 may
be performed using the mobile device 120 of FIGS. 1-2.
[0060] The method 300 includes scanning, at a first station, a
dedicated channel in a wireless network to detect information
(e.g., a neighbor report and/or access point capability
information) from an access point in the wireless network, at 302.
For example, referring to FIG. 1, the mobile device 120 may scan
the dedicated channel 150 to detect an RNR from the first access
point 110 or to detect an RNR from the second access point 130. For
example, upon entering transmission range of the first network 112
and/or the second network 132, the mobile device 120 may scan the
dedicated channel 150 (e.g., channel 6) to detect beacons or FILS
discovery frames that are broadcasted on the dedicated channel 150
via the access points 110, 130. Beacons or FILS discovery frames
broadcasted from the first access point 110 may include the first
neighbor report 114, and beacons and FILS discovery frames
broadcasted from the second access point 130 may include the second
neighbor report 134.
[0061] After scanning the dedicated channel 150 for a particular
time period, the mobile device 120 may generate and transmit (e.g.,
broadcast) the probe request 124 via the dedicated channel 150 if
the mobile device has not detected an RNR from at least one of the
access points 110, 130. The probe request 124 may indicate to the
access points 110, 130 that the mobile device 120 needs to obtain
information (e.g., an RNR) to establish a connection with a
particular access point. In response to broadcasting the probe
request 124, the mobile device 120 may receive a probe response
from at least one of the access points 110, 130. For example, the
mobile device 120 may receive a probe response including the first
neighbor report 114 from the first access point 110, a probe
response including the second neighbor report 134 from the second
access point 130, or a combination thereof.
[0062] Information about a particular access point may be obtained
from the broadcasted information, at 304. For example, referring to
FIG. 1, the mobile device 120 may detect the first neighbor report
114 broadcasted from the first access point 110. The mobile device
120 may obtain information about the second access point 130 from
the first neighbor report 114. For example, the mobile device 120
may obtain an operating class of the second access point 130, a
primary operating channel of the second access point 130, a TBTT of
the second access point 130, and/or a BSSID of the second access
point 130 from the first neighbor report 114.
[0063] A communication link with the particular access point may be
established based on the obtained information, 306. For example,
referring to FIG. 1, the mobile device 120 may establish a
communication link (e.g., initiate an authentication/association
process) with a preferred access point based on the obtained
information from the first neighbor report 114. To illustrate, the
mobile device 120 may determine the primary operating channel 164
of the home access point 160 (e.g., the preferred access point)
based on the obtained information in the neighbor report(s) 114,
134, transmit an authentication frame to the home access point 160
on the primary operating channel 164, and receive an acknowledgment
frame from the home access point 160 on the primary operating
channel 164, etc. The preferred access point may be an access point
of a network dedicated to the mobile device 120 (e.g., a "home"
network) or a network selected by a user of the mobile device
120.
[0064] The method 300 of FIG. 3 may decrease the initial link setup
time to establish a communication link between the mobile device
120 and a preferred access point may be reduced by utilizing the
dedicated channel 150 to obtain RNRs. For example, the mobile
device 120 may scan and/or probe the dedicated channel 150 to
receive RNRs from the access points 110, 130 as opposed to scanning
and/or probing multiple channels before detecting an 802.11ai
access point. Thus, utilizing the dedicated channel 150 for RNR
detection may reduce the likelihood of the mobile device 120
scanning a channel that is not actively being used by an 802.11ai
access point.
[0065] Referring to FIG. 4, another method 400 for enabling fast
initial link setup via a dedicated channel is described. The method
400 may be performed using the first access point 110 of FIGS. 1-2,
the second access point 130 of FIGS. 1-2, the third access point
260 of FIG. 2, the fourth access point 270 of FIG. 2, the fifth
access point 280 of FIG. 2, the sixth access point 290 of FIG. 2,
or a combination thereof.
[0066] The method 400 includes scanning, at an access point, a
dedicated channel for a particular time period to detect one or
more broadcasted neighbor reports from one or more corresponding
access points, at 402. For example, referring to FIG. 2, prior to
broadcasting the first neighbor report 114, the first access point
110 may scan the dedicated channel 150 for a particular time period
to detect one or more broadcasted FILS frames (including reduced
neighbor reports) from one or more corresponding access points. The
first access point 110 may scan the dedicated channel 150 for
approximately 5 ms to detect one or more RNRs from one or more
corresponding access points.
[0067] Information (e.g., a neighbor report and/or access point
capability information) may be selectively broadcast via the
dedicated channel based on the scan, at 404. For example, referring
to FIG. 2, the first access point 110 may determine whether an
access point within a close proximity has broadcasted a FILS frame
on the dedicated channel 150. In response to a determination that
an access point within a relatively close proximity has broadcasted
a FILS frame on the dedicated channel 150, the first access point
110 may suppress broadcast transmission of the first neighbor
report 114.
[0068] For example, the first access point 110 may detect and
measure the first received signal strength of the first FILS frame
from the third access point 260 during scanning operations. A
relatively high RSSI 250 indicates that the third access point 260
is in close proximity to the first access point 110. In response to
a determination that the first received signal strength of the
first FILS frame satisfies a first threshold (e.g., is greater than
or equal to a first threshold signal strength or has a relatively
high RSSI 250), the first access point 110 may suppress the
broadcast of the first neighbor report 114 via the dedicated
channel 150.
[0069] Additionally, the first access point 110 may determine
whether three or more access points within a relatively close
proximity have broadcast a FILS frame during scanning operations.
For example, the first access point 110 may detect the second FILS
frame from the fourth access point 270 and the third FILS frame
from the fifth access point 280 on the dedicated channel 150. In
addition, the first access point 110 may measure the second
received signal strength of the second FILS frame and the third
received signal strength of the third FILS frame. In response to a
determination that the each received signal strength satisfies a
second threshold (e.g., is greater than or equal to a second
threshold signal strength or has a mid-range RSSI 250), the first
access point 110 may suppress the broadcast of the first neighbor
report 114.
[0070] However, in response to a determination that there are not
any access points that have broadcasted a FILS frame on the
dedicated channel 150 with a received signal strength satisfying
the first threshold and there are not three or more access points
that have broadcasted FILS frames on the dedicated channel 150 with
a received strength satisfying the second threshold, the first
access point 110 broadcasts the first neighbor report 114 on the
dedicated channel 150. In addition, if the first access point 110
determines that the neighbor reports in the FILS frames from the
neighboring access points do not list each access point in the
first neighbor report 114, the first access point 110 may broadcast
the first neighbor report 114 via the dedicated channel 150.
[0071] The method 400 of FIG. 4 may reduce overhead (e.g.,
congestion) on the dedicated channel 150 by suppressing the
broadcast of the first neighbor report 114 when the received signal
strength of one or more neighboring access point's FILS frames on
the dedicated channel 150 satisfies a threshold. Implementing the
coordination RNR broadcast scheme described above may enable FILS
frames to be spread in time and coverage area. It will be
appreciated that the coordination scheme does not require any
messaging between access points because the access points may scan
the dedicated channel 150 (e.g., the common channel shared by each
access point) to determine received signal strengths of FILS
frames.
[0072] Referring to FIG. 5, another method 500 for enabling fast
initial link setup via a dedicated channel is described. The method
500 may be performed using the first access point 110 of FIGS. 1-2,
the second access point 130 of FIGS. 1-2, the third access point
260 of FIG. 2, the fourth access point 270 of FIG. 2, the fifth
access point 280 of FIG. 2, the sixth access point 290 of FIG. 2,
or a combination thereof.
[0073] The method 500 includes generating identifying information
at an access point, at 502. For example, referring to FIG. 1, the
first access point 114 may generate identifying information. The
identifying information may include a neighbor report (e.g., a
reduced neighbor report according to the IEEE 802.11ai protocol),
access point capability information, or a combination thereof. The
access point capability information may be carried in a FILS
indication element according to the IEEE 802.11ai protocol. In one
example, the access point capability information includes access
point security information associated with the access point and
higher layer capability information indicating higher layer
capabilities of the access point.
[0074] The identifying information may be broadcasted via a
dedicated channel in a wireless network, at 504. For example,
referring to FIG. 1, the first access point 110 may broadcast the
information via the dedicated channel 150. The dedicated channel
according to the method 500 may include a channel (e.g., a
particular channel) in a set of non-overlapping channels. For
example, the dedicated channel may include a common channel that is
shared by multiple access points in the wireless network to
broadcast neighbor reports.
[0075] According to the method 500, the access point may include an
IEEE 802.11ai access point and the wireless network may include an
IEEE 802.11 wireless network. In one example, the IEEE 802.11ai
access point includes a dual-band access point. In another example,
the IEEE 802.11ai access point includes a single-band access point.
The neighbor report may include a list of nearby access points in
the wireless network. In one example, each access point in the list
of nearby access points is operating on a distinct channel. In one
example, the neighbor report is included in a one of a beacon frame
broadcasted from the access point via the dedicated channel, a FILS
discovery frame broadcasted from the access point via the dedicated
channel, or a probe response from the access point.
[0076] The method 500 may also include scanning the dedicated
channel for a particular time period to detect one or more
broadcasted neighbor reports from one or more corresponding access
points prior to broadcasting the identifying information. The
access point determines whether to suppress the broadcast of the
identifying information based on corresponding signal strengths of
the one or more broadcasted neighbor reports. For example, a
broadcast of a particular neighbor report from the access point may
be suppressed when a received signal strength of another neighbor
report broadcasted from another access point satisfies a first
threshold. As another example, a broadcast of a particular neighbor
report from the access point may be suppressed when signal
strengths of corresponding neighbor reports broadcasted from other
access points satisfy a second threshold. In one example, the
signal strengths of corresponding neighbor reports correspond to at
least three signal strengths of three corresponding neighbor
reports. The method 500 may also include broadcasting a second
neighbor report and second access point capability information on a
primary operating channel of the access point.
[0077] Referring to FIG. 6, another method 600 for enabling fast
initial link setup via a dedicated channel is described. The method
600 may be performed using the mobile device 120 of FIGS. 1-2.
[0078] The method 600 includes scanning, at a first station, a
dedicated channel in a wireless network to detect broadcasted
information from an access point in the wireless network, at 602.
For example, referring to FIG. 1, the first station 120 may scan
the dedicated channel 150 to detect broadcasted information from
one of the access points 110, 130.
[0079] Identifying information regarding a particular identifiable
access point may be obtained from the broadcasted information, at
604. For example, referring to FIG. 1, the first station 120 may
obtain identifying information regarding a particular identifiable
access point in the wireless network based on the broadcasted
information. The broadcasted information may include a neighbor
report (e.g., a reduced neighbor report according to an IEEE
802.11ai protocol), access point capability information, or a
combination thereof. The access point capability information may be
carried in a FILS indication element according to the IEEE 802.11ai
protocol. The access point capability information may include
access point security information associated with a particular
identifiable access point and higher layer capability information
indicating higher layer capabilities of the particular identifiable
access point. The neighbor report may be included in one of a
beacon frame broadcasted from the access point via the dedicated
channel, a FILS discovery frame broadcasted from the access point
via the dedicated channel, or a probe response from the access
point.
[0080] According to the method 600, the dedicated may include a
channel (e.g., a particular channel) in a set of non-overlapping
channels. In one example, the dedicated channel comprises a common
channel that is shared by multiple access points in the wireless
network to broadcast neighbor reports. The access point may include
an IEEE 802.11ai access point and the wireless network may include
an IEEE 802.11 wireless network. In one example, the IEEE 802.11ai
access point includes a dual-band access point. In another example,
the IEEE 802.11ai access point includes a single-band access point.
The neighbor report according to the method 600 may include a list
of nearby access points in the wireless network. Each access point
in the list of nearby access points may operate on a distinct
channel.
[0081] The method 600 may also include establishing a communication
link with the particular identifiable access point based on the
broadcasted information. For example, the method 600 may include
determining a primary operating channel of the particular
identifiable access point based on the broadcasted information. The
method 600 may also include transmitting an authentication frame to
the particular identifiable access point via the primary operating
channel. The method 600 may also include receiving an
acknowledgment frame from the particular identifiable access
point.
[0082] The method 600 may also include broadcasting, at the first
station, a probe request via the dedicated channel after a
particular time period has elapsed without detecting the
broadcasted information. The method 600 may also include receiving
a probe response from the access point via the dedicated channel in
response to broadcasting the probe request. The probe response may
include the broadcasted information according to the method
600.
[0083] The method 600 of FIG. 6 may decrease the initial link setup
time to establish a communication link between the mobile device
120 and a preferred access point may be reduced by utilizing the
dedicated channel 150 to obtain neighbor reports and access point
capability information. For example, the mobile device 120 may scan
and/or probe the dedicated channel 150 to neighbor reports and
access point capability information from the access points 110, 130
as opposed to scanning and/or probing multiple channels before
detecting an 802.11ai access point. Thus, utilizing the dedicated
channel 150 for neighbor report detection may reduce the likelihood
of the mobile device 120 scanning a channel that is not actively
being used by an 802.11ai access point.
[0084] Referring to FIG. 7, a block diagram of a wireless
communication device is depicted and generally designated 700. The
device 700 includes a processor 710, such as a digital signal
processor, coupled to a memory 732. In one example, the device 700,
or components thereof, may correspond to the access points 110, 130
of FIGS. 1-2, the access points 260, 270, 280, 290 of FIG. 2, or
components thereof. In another example, the device 700 may
correspond to the mobile device 120 of FIGS. 1-2 or components
thereof.
[0085] The processor 710 may be configured to execute software
(e.g., a program of one or more instructions 768) stored in the
memory 732. Additionally or alternatively, the processor 710 may be
configured to implement one or more instructions stored in a memory
of a wireless interface 740 (e.g., an IEEE 802.11 wireless
interface). In one example (e.g., when the wireless device 700
corresponds to an access point), the processor 710 may be
configured to operate in accordance with the method 400 of FIG. 4
and/or the method 500 of FIG. 5. For example, the processor 710 may
include neighbor query/neighbor report logic 764 to execute the
method 400 of FIG. 4 and/or the method 500 of FIG. 5.
[0086] In another example (e.g., when the wireless device 700
corresponds to the mobile device 120), the processor 710 may be
configured to operate in accordance with the method 300 of FIG. 3
and/or the method 600 of FIG. 6. For example, the processor 710 may
include neighbor query/neighbor report logic 764 to execute the
method 300 of FIG. 3 and/or the method 600 of FIG. 6. The processor
710 may also be configured to receive, determine, and/or store one
or more neighbor reports 770 and/or one or more probe requests 772.
For example, the one or more neighbor reports 770 and/or one or
more probe requests 772 may be stored in the memory 732. One or
more neighbor reports 770 may include the first neighbor report 114
and/or the second neighbor report 134, as illustrative,
non-limiting examples. The one or more probe requests 772 may
include a probe request generated by a mobile device, such as the
mobile device 120 of FIGS. 1-2.
[0087] The wireless interface 740 may be coupled to the processor
710 and to an antenna 742. For example, the wireless interface 740
may be coupled to the antenna 742 via a transceiver 746, such that
wireless data received via the antenna 742 may be provided to the
processor 710.
[0088] When the wireless device 700 corresponds to the mobile
device 120, a coder/decoder (CODEC) 734 can also be coupled to the
processor 710. A speaker 736 and a microphone 738 can be coupled to
the CODEC 734. A display controller 726 can be coupled to the
processor 710 and to a display device 728. The processor 710, the
display controller 726, the memory 732, the CODEC 734, and the
wireless interface 740, are included in a system-in-package or
system-on-chip device 722. An input device 730 and a power supply
744 are coupled to the system-on-chip device 722. Moreover, as
illustrated in FIG. 7, the display device 728, the input device
730, the speaker 736, the microphone 738, the antenna 742, and the
power supply 744 are external to the system-on-chip device 722.
However, each of the display device 728, the input device 730, the
speaker 736, the microphone 738, the antenna 742, and the power
supply 744 can be coupled to one or more components of the
system-on-chip device 722, such as one or more interfaces or
controllers.
[0089] In conjunction with the described techniques, an apparatus
includes means for scanning a dedicated channel in a wireless
network to detect broadcasted information from an access point in
the wireless network. For example, the means for scanning may
include the wireless interface 740 of FIG. 7, the transceiver 746
of FIG. 7, the processor 710 programmed to execute the instructions
768 of FIG. 7, one or more other devices, circuits, modules, or
instructions to scan the dedicated channel, or a combination
thereof.
[0090] The apparatus also includes means for obtaining identifying
information regarding a particular access point from the
broadcasted information. For example, the means for obtaining the
identifying information may include the wireless interface 740 of
FIG. 7, the processor 710 programmed to execute the instructions
768 of FIG. 7, one or more other devices, circuits, modules, or
instructions to obtain information of the particular access point,
or a combination thereof. The broadcasted information includes a
neighbor report (e.g., a reduced neighbor report), access point
capability information (e.g., access point security information
associated with the particular identifiable access point and higher
layer capability information indicating higher layer capabilities
of the particular identifiable access point), or a combination
thereof. The access point capability information is carried in a
FILS indication element according to an IEEE 802.11ai protocol.
[0091] In conjunction with the described techniques, an apparatus
includes means for determining a signal strength of at least one
broadcasted neighbor report on a dedicated channel in a wireless
network. For example, the means for determining the signal strength
may include the processor 710 programmed to executed the
instructions 768 of FIG. 7, one or more other devices, circuits,
modules, or instructions to determine the signal strength of at
least one broadcasted reduced neighbor report on the dedicated
channel, or a combination thereof.
[0092] The apparatus also includes means for broadcasting
identifying information via the dedicated channel in response to a
determination that the signal strength fails to satisfy a
threshold. For example, the means for broadcasting may include the
wireless interface 740 of FIG. 5, the transceiver 746 of FIG. 7,
the antenna 742 of FIG. 7, the processor 710 programmed to executed
the instructions 768 of FIG. 7, one or more other devices,
circuits, modules, or instructions to broadcast the reduced
neighbor report, or a combination thereof. The identifying
information includes a neighbor report (e.g., a reduced neighbor
report), access point capability information (e.g., access point
security information associated with the access point and higher
layer capability information indicating higher layer capabilities
of the access point), or a combination thereof. The access point
capability information is carried in a FILS indication element
according to an IEEE 802.11ai protocol.
[0093] Those of skill in the art would further appreciate that the
various illustrative logical blocks, configurations, modules,
circuits, and algorithm steps described in connection with the
techniques disclosed herein may be implemented as electronic
hardware, computer software executed by a processor, or
combinations of both. Various illustrative components, blocks,
configurations, modules, circuits, and steps have been described
above generally in terms of their functionality. Whether such
functionality is implemented as hardware or processor executable
instructions depends upon the particular application and design
constraints imposed on the overall system. Skilled artisans may
implement the described functionality in varying ways for each
particular application, but such implementation decisions should
not be interpreted as causing a departure from the scope of the
present disclosure.
[0094] The steps of a method or algorithm described in connection
with the techniques disclosed herein may be embodied directly in
hardware, in a software module executed by a processor, or in a
combination of the two. A software module may reside in random
access memory (RAM), flash memory, read-only memory (ROM),
programmable read-only memory (PROM), erasable programmable
read-only memory (EPROM), electrically erasable programmable
read-only memory (EEPROM), registers, hard disk, a removable disk,
a compact disc read-only memory (CD-ROM), or any other form of
non-transient (e.g., non-transitory) storage medium known in the
art. An exemplary storage medium is coupled to the processor such
that the processor can read information from, and write information
to, the storage medium. In the alternative, the storage medium may
be integral to the processor. The processor and the storage medium
may reside in an application-specific integrated circuit (ASIC).
The ASIC may reside in a computing device or a user terminal. In
the alternative, the processor and the storage medium may reside as
discrete components in a computing device or user terminal.
[0095] The previous description of the disclosed techniques is
provided to enable a person skilled in the art to make or use the
disclosed techniques. Various modifications to these techniques
will be readily apparent to those skilled in the art, and the
principles defined herein may be applied to other techniques
without departing from the scope of the disclosure. Thus, the
present disclosure is not intended to be limited to the embodiments
shown herein but is to be accorded the widest scope possible
consistent with the principles and novel features as defined by the
following claims.
* * * * *