U.S. patent application number 14/681007 was filed with the patent office on 2015-07-30 for quality-of-service (qos)-based association with a new network using background network scanning.
This patent application is currently assigned to Broadcom Corporation. The applicant listed for this patent is Broadcom Corporation. Invention is credited to James D. Bennett, Jeyhan Karaoguz, Nambirajan Seshadri.
Application Number | 20150215858 14/681007 |
Document ID | / |
Family ID | 35733005 |
Filed Date | 2015-07-30 |
United States Patent
Application |
20150215858 |
Kind Code |
A1 |
Karaoguz; Jeyhan ; et
al. |
July 30, 2015 |
Quality-Of-Service (QoS)-Based Association With A New Network Using
Background Network Scanning
Abstract
A method and device support the use of background network
scanning to enable association with a first and at least a second
wireless network, for the exchange of exchange of multimedia
information. Representative embodiments of the present invention
may sniff radio frequency spectrum and determine at least one
characteristic of detected wireless networks having capacity for
exchange of the multimedia information. More than one wireless
network may be identified for use in exchanging the multimedia
information, which may be communicated concurrently over the
identified wireless networks. User defined criteria may be employed
in adjusting communication of the multimedia information to meet a
quality of service level desired by a user. A lack of wireless
network capacity may result in adjustments to, for example,
protocols used to represent multimedia information, frame rate, and
spatial or color resolution, in order to maintain or enable
communication.
Inventors: |
Karaoguz; Jeyhan; (Irvine,
CA) ; Bennett; James D.; (Hroznetin, CZ) ;
Seshadri; Nambirajan; (Irvine, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Broadcom Corporation |
Irvine |
CA |
US |
|
|
Assignee: |
Broadcom Corporation
|
Family ID: |
35733005 |
Appl. No.: |
14/681007 |
Filed: |
April 7, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11094048 |
Mar 30, 2005 |
9031568 |
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14681007 |
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60591735 |
Jul 28, 2004 |
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60591847 |
Jul 28, 2004 |
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60591844 |
Jul 28, 2004 |
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60591841 |
Jul 28, 2004 |
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60591845 |
Jul 28, 2004 |
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60591843 |
Jul 28, 2004 |
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60591842 |
Jul 28, 2004 |
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Current U.S.
Class: |
455/434 |
Current CPC
Class: |
H04W 36/28 20130101;
H04W 48/16 20130101; H04W 72/085 20130101; H04N 21/4126 20130101;
H04W 28/24 20130101; H04W 36/26 20130101 |
International
Class: |
H04W 48/16 20060101
H04W048/16; H04W 28/24 20060101 H04W028/24; H04W 72/08 20060101
H04W072/08 |
Claims
1. A method supporting quality of service based association with a
new wireless communication network using background network
scanning, the method comprising: establishing communication via a
first wireless network; detecting at least a second wireless
network by scanning radio frequency spectrum; determining at least
one characteristic of the at least a second wireless network;
identifying network capacity among the first wireless network and
the at least a second wireless network sufficient for exchange of
multimedia information; exchanging multimedia information using
identified network capacity; detecting insufficient capacity for
exchange of the multimedia information; requesting input through a
user interface related to the at least one characteristic in
response to the detecting insufficient capacity; and adjusting
communication of multimedia information according to the input.
2. The method according to claim 1, wherein the requesting input
comprises providing an option to purchase additional bandwidth.
3. The method according to claim 1, wherein the requesting input
comprises providing an option to reduce a quality level of the
multimedia information.
4. The method according to claim 1, wherein the requesting input
comprises providing an option to identify additional communication
paths for exchange of the multimedia information.
5. The method according to claim 1 wherein the first and the at
least a second wireless network comprise one of: a wireless wide
area network, a wireless local area network, and a personal area
network.
6. The method according to claim 1 wherein the at least one
characteristic comprises one of: a radio frequency, an air
interface protocol, a bandwidth, and a parameter used for network
access.
7. The method according to claim 1 wherein multimedia information
comprises one of: streaming video, broadcast video, voice, digital
data, text, digitized audio, digitized still images, digitized
video, and digitized music.
8. The method according to claim 1 wherein adjusting communication
of multimedia information comprises identifying additional network
capacity for communication of the multimedia information, from the
at least a second wireless network.
9. The method according to claim 8 wherein the additional network
capacity is on a wireless network different from those previously
identified.
10. The method according to claim 1 wherein the adjusting
communication of multimedia information comprises one of: changing
a protocol used to represent the multimedia information,
transcoding the multimedia information, and changing a resolution
of the multimedia information.
11. The method according to claim 1 wherein exchanging multimedia
information comprises concurrently exchanging the multimedia
information using the first wireless network and the at least one
second wireless network.
12. The method according to claim 1 wherein exchanging multimedia
information comprises individually exchanging portions of the
multimedia information using each of the first wireless network and
the at least a second wireless network.
13. The method according to claim 1 wherein the first wireless
network and the at least a second wireless network employ different
air interface protocols.
14. A mobile access device supporting quality of service based
association with a new network using background network scanning,
the device comprising: at least one wireless interface capable of
exchanging multimedia information with a first wireless network
while scanning radio frequency spectrum to detect at least a second
wireless network, wherein the first wireless network supports a
first network capacity for exchange of multimedia information and
the at least a second wireless network supports at least a second
network capacity for exchange of multimedia information; storage
comprising at least one user-defined criteria employed in selecting
wireless networks for exchange of multimedia information; software
resident in memory of the device, the software executable for
determining at least one characteristic of the at least a second
wireless network, for identifying network capacity among the first
wireless network and the at least a second wireless network
sufficient for exchange of multimedia information, for requesting
input through a user interface in response to the identified
network capacity; and the device capable of adjusting communication
of multimedia information based upon the input and the identified
network capacity.
15. The device according to claim 14, wherein the requesting input
comprises providing an option to purchase additional bandwidth.
16. The device according to claim 14, wherein the requesting input
comprises providing an option to reduce a quality level of the
multimedia information.
17. The device according to claim 14, wherein the requesting input
comprises providing an option to identify additional communication
paths for exchange of the multimedia information.
18. The device according to claim 14 wherein the first and the at
least a second wireless network comprise one of: a wireless wide
area network, a wireless local area network, and a personal area
network.
19. The device according to claim 14 wherein the adjusting
communication of multimedia information comprises one of: changing
a protocol used to represent the multimedia information,
transcoding the multimedia information, and changing a resolution
of the multimedia information.
20. A method supporting quality of service based association with a
new wireless communication network using background network
scanning, the method comprising: establishing communication via a
first wireless network; detecting at least a second wireless
network by sniffing radio frequency spectrum, wherein the first and
the at least a second wireless network comprise one of: a wireless
wide area network, a wireless local area network, and a personal
area network; determining at least one characteristic of the at
least a second wireless network; identifying network capacity among
the first wireless network and the at least a second wireless
network sufficient for exchange of multimedia information;
exchanging multimedia information using identified network
capacity; detecting insufficient capacity for exchange of the
multimedia information; requesting input through a user interface
in response to the detecting insufficient capacity; and adjusting
communication of multimedia information according to the input and
the identified network capacity.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is a continuation application of
non-provisional application Ser. No. 11/094,048, filed Mar. 30,
2004, and entitled "Quality-Of-Service (QoS)-Based Association With
A New Network Using Background Network Scanning," which makes
reference to, claims priority to, and claims the benefit of the
following United States Provisional Patent Applications, the
complete subject matter of each of which is hereby incorporated
herein by reference, in its entirety.
TABLE-US-00001 Date Serial No. Title Filed 60/591,735 Method and
System for Handoff Through Jul. 28, Simulcasting 2004 60/591,847
Method and System for Handling Calls Through Jul. 28, Simulcasting
2004 60/591,844 Method and System for Handling Multimedia Jul. 28,
Information Through Simulcasting 2004 60/591,841 Method and System
for Simulcasting or Jul. 28, Multicasting Multimedia Information in
a 2004 Broadband Wired and/or Wireless LAN or Personal Area Network
(PAN) Via a Broadband Access Gateway 60/591,845 Method and System
for Consuming Simulcasted Jul. 28, and Multicasted Content in a
PAN/WAN/WLAN 2004 Serviced by a Broadband Access Gateway 60/591,843
Method and System for Handoff of a Multimedia Jul. 28, Stream by
Sniffing 2004 60/591,842 Method and System for Sniffing to Provide
Jul. 28, Association with a New Network 2004
[0002] The present application also makes reference to U.S. patent
application Ser. No. 11/021,294, filed Dec. 23, 2004, and entitled
"Method And System For Extended Network Access Services Advertising
Via A Broadband Access Gateway", the complete subject matter of
which is hereby incorporated herein by reference, in its
entirety.
[0003] The present application also makes reference to U.S. patent
application Ser. No. 11/094,045, filed Mar. 30, 2005, entitled
"Handling Of Multimedia Call Sessions And Attachments Using
Multi-Network Simulcasting", the complete subject matter of which
is hereby incorporated herein by reference, in its entirety.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0004] [Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[0005] [Not Applicable]
BACKGROUND OF THE INVENTION
[0006] One major common problem faced by cellular and landline
service providers is market competition. In today's climate of
competitive markets, cellular service providers have found that one
way for them to grow market share and defend their businesses is to
be proactive and form alliances, and to partner with landline
service providers. In addition, cellular service providers seek to
differentiate their service offerings, and to capture the largest
portion of market revenue by meeting an ever increasing demand for
access to a wide range of media forms such as MP3 encoded audio,
still and video imaging, data, instant messaging, and email. In a
similar manner, the landline service providers have found that to
grow market share and ward off competition, they too must be
proactive and form alliances, and to partner with cellular service
providers. Support for broad economical access to these converging
forms of communication is needed to enable unfettered market
growth, and to support the development and use of new handheld
devices needed to provide increasing levels of mobile multimedia
communication functionality.
[0007] Although the formation of alliances and partnerships between
cellular service providers and landline service providers may help
to ward off competition, such alliances and partnerships are faced
with other problems. For example, the erection of cellular
infrastructure such as cellular towers may be an expensive venture
since this may require acquisition of real estate, whether in the
form of outright purchases or through leasing. Cellular
infrastructure also requires the establishment of one or more
expensive backbone links to handle core network traffic. Another
cellular-related problem is that the cellular signals do not
penetrate and propagate in buildings such as homes and offices very
well. This is especially true with the frequencies that are
typically utilized in the United States, which may vary between 800
MHz and 1900 MHz or 1.9 GHz.
[0008] As users of wireless communication devices move about, the
quality of the wireless communication path may change drastically.
In some cases, conditions degrade to the point that the wireless
communication path is dropped, when the wireless access device or
the network determines that satisfactory communication is no longer
possible. The decision to end the call is normally made without
user input, and is generally based upon criteria determined by the
maker of the wireless access device and/or the network
infrastructure equipment. Although their current wireless network
may be impaired, users of wireless access devices may migrate
within the coverage areas of a number of other wireless networks
without knowing of their existence.
[0009] In other circumstances, a user may be aware of the existence
of the other wireless networks, and may take advantage of such
networks when in a geographic location served by a known wireless
network. Many more wireless networks may exist than those of which
the user is aware, and the user of a wireless access device may
therefore be unaware of the opportunity to make use of those other
networks for communication. Some of the available networks may be
suitable for the communication activities of a particular access
device user, while others may not. In addition, wireless service
providers are continually adding new network capabilities and
features, and new wireless service providers enter the market each
day. Depending upon the number of active subscribers and/or users,
and the activities of each subscriber and/or user, a wireless
network that one day provides satisfactory quality of service may,
on another day or at another time, be unable to meet a particular
wireless access device user's needs.
[0010] Further limitations and disadvantages of conventional and
traditional approaches will become apparent to one of skill in the
art, through comparison of such systems with some aspects of the
present invention as set forth in the remainder of the present
application with reference to the drawings.
BRIEF SUMMARY OF THE INVENTION
[0011] A method and device supporting quality of service based
association with a new network using background network scanning,
substantially as shown in and/or described in connection with at
least one of the figures, as set forth more completely in the
claims.
[0012] These and other advantages, aspects and novel features of
the present invention, as well as details of an illustrated
embodiment thereof, will be more fully understood from the
following description and drawings.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1 is a block diagram illustrating an architecture of an
exemplary communications system in which a representative
embodiment of the present invention may be practiced.
[0014] FIG. 2 shows a block diagram illustrating an exemplary
communication system that may be utilized for quality of service
based association with a new network using background network
scanning of radio frequency spectrum in, for example, a broadband
wireless local area network (WLAN) or personal area network (PAN),
in accordance with a representative embodiment of the present
invention.
[0015] FIG. 3A shows an exemplary display of a wireless access
device that may correspond to, for example, the wireless access
device of FIG. 2 upon encountering wireless network impairments, in
accordance with a representative embodiment of the present
invention.
[0016] FIG. 3B shows another exemplary display of a wireless access
device that may correspond to, for example, the wireless access
device of FIG. 2 upon encountering wireless network impairments in
which a user is prompted to choose a remedy, in accordance with a
representative embodiment of the present invention.
[0017] FIG. 4 shows an exemplary display of a wireless access
device that may correspond to, for example, the wireless access
device of FIG. 2 following a user attempt to engage in a multimedia
exchange while in a service area subject to wireless network
impairments, in accordance with a representative embodiment of the
present invention.
[0018] FIGS. 5A and 5B show message exchange diagrams that
illustrate the use of background network scanning in the
association of a mobile access device that may correspond to the
mobile access device of FIG. 2 with wireless networks during the
establishment and progression through an exemplary multimedia
information exchange, in accordance with a representative
embodiment of the present invention.
[0019] FIG. 6 is a flowchart illustrating an exemplary method of
supporting association of a mobile access device such as, for
example, the mobile access device of FIG. 2 using background
network scanning, in accordance with a representative embodiment of
the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Aspects of the present invention relate to communication
over hybrid wired and wireless networks. More specifically, certain
embodiments of the present invention relate to a method and system
for quality of service based association with a new network using
background network scanning of a wireless network environment. In a
representative embodiment of the present invention, scanning may
comprise sniffing of radio frequency spectrum. A representative
embodiment of the present invention allows a user of a wireless
access device greater freedom of movement, and a wider variety of
communication options than is available using conventional
technology.
[0021] An aspect of the invention provides seamless merging of wide
area networks (WANs), from any kind of wired and/or wireless wide
area networks, to pockets of wired and/or wireless local area
networks (WLANs) and personal area network (PANs), which may be
located in homes or other environment such as an office or
business. The merging of these various types of networks enables
transparent communication of all types of media between access
devices, which may be wired or wirelessly coupled to one or more of
these networks. Seamless communication may be provided to access
devices as they transition from one type of network to another type
of network. In a representative embodiment of the present
invention, a user of a wireless access device engaged in a
communication session may be kept aware of other wireless networks
providing service at their present location, and may elect to make
use of one of those other networks to continue their current
communication activity.
[0022] FIG. 1 is a block diagram illustrating an architecture of an
exemplary communications system in which a representative
embodiment of the present invention may be practiced. Referring to
FIG. 1, there is shown a first location 102, a second location 104,
a broadband access provider (BAP) 106, a public switched telephone
network (PSTN) 108, a transport network 110, wireless service
provider networks including a CDMA network 112 and a GSM/EDGE/GPRS
network 114, and access devices 122, 124, 126, and 128. The first
location 102 comprises a gateway 118 having a modem 116, a wireless
interface(s) block 120, and the access devices 122, 124. The access
devices 122, 124, 126, 128 may comprise, for example, a mobile
multimedia handset having a high level of functionality such as,
for example, that of one or more of a digital video or still
camera, a portable audio (MP3) player, a personal digital
assistant, and a voice handset. The access devices 122, 124, 126,
128 may be capable of operating using, for example, a personal area
network and/or wireless local area network compliant with, for
example, Bluetooth, IEEE 802.11 a/b/g/n, and/or IEEE 802.15.3a
ultra-wideband standards. The second location 104 comprises a
router 130 having a modem 132, and a plurality of wireless access
devices. The plurality of wireless access devices at the second
location 104 may comprise a personal computer (PC) 138, a laptop
136 and a wireless personal digital assistant (PDA) 134. A
peripheral such as a digital camera 142 may be coupled to the
personal computer 138. Other peripherals such as printers, digital
scanners, speakers, and the like, which are not shown, may also be
coupled to the personal computer 138 and/or laptop 136. The
wireless interface block 120 may comprise a plurality of interfaces
such as a Bluetooth interface, an IEEE 802.15.3a ultra-wideband
interface, and any combination of an IEEE 802.11 a, b, g and/or n
interface.
[0023] FIG. 1 also comprises an "other broadband access provider"
block 144, an "other cellular/PCS service provider" block 146, a
central control and management block 148, and content provider 150.
The "other broadband access provider block 144" may be, for
example, a cable, DSL, or other type of broadband access provider.
The central control and management block 148 may comprise suitable
logic, circuitry and/or code that may be adapted to handle content
delivery and security functions such as authentication, validation,
key or certificate management, and authorization. The central
control and management block 148 may also be adapted to handle
provisioning, service management, and accounting. In a
representative embodiment of the present invention, the central
control and management block 148 may establish communications links
with, for example, the gateway 118, the broadband access provider
106, the other broadband access provider 144, the other
cellular/PCS service provider 146, the CDMA network 112, and the
GSM/EDGE/GPRS network 114 using actual or virtual connections.
[0024] The broadband access provider 106 may be, for example, a
cable operator, telephone company, or satellite operator providing
Internet access along with other communication services. In
instances where BAP 106 is a telephone company, broadband service
to locations 102, 104 may be provided via DSL or other broadband
access technology. Accordingly, the modems 116, 132 may be DSL
modems. In instances where BAP 106 is a cable operator, broadband
service to locations 102, 104 may be provided via cable.
Accordingly, the modems 116, 132 may be DOCSIS compliant or other
type of cable modem. Given the rapid decrease in the cost of leased
telephone lines over the past decade or more, the connection to the
location 102, 104 may also be T1 or T3 connections. For example, a
switch located at a central office (CO) (not shown) may be utilized
to couple a T1 or T3 connection between the second location 104 and
the PSTN 108.
[0025] The gateway 118 may comprise an integrated DSL modem, cable
modem or other high-speed modem that may be required for handling a
connection such as a T1 or T3 connection. Alternatively, the
gateway 118 may be coupled to an external DSL modem, cable modem or
other high-speed modem that may be capable of handling connections
such as a T1 or a T3 connection. The gateway 118 may be adapted so
that it has access to protocol stack information that may be
related to the GSM and/or CDMA networks 114, 112, respectively. The
gateway 118 may also be adapted to provide protocol support for
communication with "other cellular/PCS service provider" block
146.
[0026] Each of the CDMA and GSM/EDGE/GPRS networks 112, 114 may
comprise a plurality of cell sites (a/k/a cellular towers) that are
located in geographical cells within each of the networks. Within
the GSM/EDGE/GPRS network 114, each of the cell sites such as, for
example, cell site 114a may comprise a base transceiver station
(BTS), and one or more base transceiver stations (BTSs) may be
coupled to wireless carrier central office 114b. The wireless
carrier central office 114b may comprise a base station
controller/radio network controller (BSC/RNC) such as BSC/RNC 114d.
One or more base station controllers/radio network controllers
(BSCs/RNCs) may be coupled to the core network 114e, that comprises
a network edge switch called a mobile switching center (MSC), such
as MSC 114g, and a serving GPRS support node (SGSN)/packet data
serving node (PDSN) 114f, of the GSM/EDGE/GPRS network 114. The
mobile switching center may be coupled to, for example, the PSTN
108 via the transport network 110. As an access device moves out of
range of a first cell site to within range of a second cell site,
the decrease signal power received from the first cell site and the
increase in signal power received from the second cell site causes
initiation of handoff of a call from the first cell site to the
second cell site. In cases where there is no second cell site to
handoff to, the call may be maintained by the first cell site power
until it is attenuated to a threshold where it is no longer
feasible to maintain the call. At the point where the power reaches
or falls below this threshold, the call may drop and any related
call resources may be relinquished. In a home and/or office
environment, it may be desirable to have a second network to which
the call may be handed off.
[0027] As an illustration, a user may be on their way home and as
the user approaches their home, the signal may fall below a minimum
signal power threshold that is required to maintain a call.
However, instead of dropping the call, the call may be handed off
to, for example, a PAN or a wireless local area network (WLAN) that
may be located within the user's home or an unlicensed wireless
access system that may be located in the user's home. For example,
with reference to FIG. 1, as access device 126 migrates from the
vicinity of the serving cell site 114a in GSM/EDGE/GPRS network 114
towards the wireless interface 120 in the first location 102, the
call may be handed off from the cell site 114a of the GSM/EDGE/GPRS
network 114 to the wireless interface 120 coupled to the gateway
(GW) 118 at the first location 102. Accordingly, instead of the
call being dropped, the call has been seamlessly handed off and is
now being handled by the gateway 118 via the wireless interface
120. The resulting wireless data may then be communicated to the
GSM/EDGE/GPRS network 114 via the broadband connection to the BAP
106 which is connected to the broadband wireless local area network
controller (BWC) 114c.
[0028] In a representative embodiment of the present invention, a
number of wireless performance prediction parameters (WPPP) or
attributes may be employed during the operation of a communication
network such as, for example, an Institute of Electrical and
Electronics Engineers (IEEE) 802.11 communication network. These
wireless link attributes may be exchanged by an infrastructure
transceiver device such as, for example, a wireless access point
(WAP) or a broadband access gateway such as the broadband access
gateway 118, for example, and a mobile communication device such as
the mobile access device 124, for example. Such an exchange of
parameters or attributes may permit the endpoints of a wireless
communication link in a representative embodiment of the present
invention to decide, for example, whether to make adjustments to
the current level of service being provided, or to switch from use
of a first communication network to add or switch to a second
communication network. The wireless performance prediction
attributes used in such a decision may be based on a
signal-to-noise ratio (SNR), a frame error rate, a fading
characteristic of the communication link, and a measure of
throughput, to name only a few examples. If the wireless
performance prediction parameters or attributes indicate that the
level of service offered by a current serving communication network
is below an expected and/or acceptable level, then an access point
or broadband access gateway of the network may, for example,
decrease the bandwidth required of the communication link by, for
example, decreasing the resolution of the multimedia information
transferred to the serviced mobile access device such as the mobile
access device 124, for example. A user of the mobile access device,
however, may not be satisfied with a reduced resolution, that may
not meet the quality of service (QoS) expectations of the user.
Accordingly, in a representative embodiment of the present
invention, a user of a mobile access device may be offered an
option to purchase additional bandwidth to attain the expected
and/or acceptable level of service. Given this option, the user of
the mobile access device may opt to pay the cost for the additional
bandwidth.
[0029] In another representative embodiment of the present
invention, an access device may determine the QoS that is being
received from its serving communication network based on these
wireless performance prediction parameters, and may compare the QoS
currently being provided, with the QoS that a newly detected or
"sniffed" communication network may be able to provide. During
operation, the wireless access device may observe and analyze
(sniff) portions of the radio frequency spectrum for which it is
equipped, and may derive wireless performance prediction parameters
with the sniffed network(s). If the wireless performance prediction
parameters indicate that the newly sniffed communication network
may provide a better QoS than the current serving communication
network, the mobile access device may switch from the current
serving communication network to the newly sniffed communication
network. However, if the wireless performance prediction parameters
indicate that the newly sniffed communication network would provide
a lower QoS than the current serving communication network, then
the access device may not initiate a switch from the current
serving communication network to the newly sniffed communication
network. In this regard, the mobile access device may continue
receiving service from the current servicing communication network
and may also continue scanning and/or sniffing to locate other
compatible networks. The decision to switch between wireless
communication networks may be initiated in hardware (e.g., in a
hardware circuit such as an integrated circuit) or it may be
initiated from an application layer by software or firmware.
[0030] In yet another representative embodiment of the present
invention, based on the wireless performance prediction parameters,
a decision may be made by the mobile access device to communicate
using multiple wireless networks. In one representative embodiment
of the present invention, the mobile access device may repeatedly
bounce or switch between two or more wireless communication
networks, in order to maintain at least a minimal level of service.
In some representative embodiments, this minimal level of service
may allow, for example, short message service (SMS) communication
or other communications modes operating at lower bit rates and
involving reduced levels of call processing. Any communication that
required bandwidth beyond a specified threshold such as, for
example, multimedia communication, may be prohibited or restricted.
Accordingly, as a mobile access device such as, for example, the
mobile access device 124 of FIG. 1 moves from one location to
another, and the signal quality for the serving and neighboring
communication networks repeatedly degrades and improves, a
representative embodiment of the present invention may reduce the
QoS level of communication rather than ceasing communication
altogether, in order to provide this minimal amount of
communication. In a representative embodiment in accordance with
the present invention, the decision to bounce or keep switching
between communication networks may be initiated in silicon (e.g.,
within integrated circuit device(s)) or it may be initiated from
the application layer such as in software and/or firmware, for
example.
[0031] In a representative embodiment of the present invention, at
least a portion of the multimedia information within the received
signal may be cached or temporarily stored, whenever the signal
degrades. This may occur during periods when a mobile access device
such as mobile access device 124, for example, is bouncing between
two or more networks. The behavior of bouncing or switching between
networks may take into consideration the type of multimedia
information being exchanged. In accordance with a representative
embodiment of the present invention, hysteresis may be added so as
to prevent or otherwise limit a manner in which bouncing between
communication networks occurs. For example, if a multimedia
information stream comprising synchronization information such as,
for example, a Moving Picture Experts Group (MPEG) data stream is
being received, hysteresis may be employed to prevent bouncing
every time an I-frame (a.k.a., I-picture) or other synchronization
frame is received.
[0032] FIG. 2 shows a block diagram illustrating an exemplary
communication system 200 that may be utilized for quality of
service based association with a new network using background
network scanning of radio frequency spectrum in, for example, a
broadband wireless local area network (WLAN) or personal area
network (PAN), in accordance with a representative embodiment of
the present invention. The exemplary communication system 200 of
FIG. 2 may provide handoff through scanning for wireless network
traffic, for an active subscriber, from a wireless service provider
servicing the active subscriber to a broadband wired and/or a
wireless LAN (WLAN), and/or PAN using a broadband access gateway.
In a representative embodiment of the present invention, scanning
may comprise sniffing of radio frequency spectrum. Referring to
FIG. 2, there is shown a first location 202, a broadband access
provider (BAP) 206, a transport network block 232, an Internet 204,
a WANs, PSTN, etc networks block 208, a content providers block
210, wireless wide area service provider networks 212, 214, access
points 205, 207, 209, and a plurality of mobile access devices 224,
226, 228. The illustration of FIG. 2 also comprises a central
control and management block 248 that may correspond, for example,
to the central control and management block 148 of FIG. 1.
[0033] The first location 202 comprises a broadband access gateway
218 with a modem 216, a wireless interface 220, and a user profile
219. The first location may be a home, and the broadband access
gateway 218 with the modem 216 and the wireless interface 220 may
support a personal area network (PAN) and/or wireless local area
network (WLAN), and may be referred to as a home network 202a. The
wireless interface 220 may comprise a plurality of interfaces such
as a Bluetooth interface, an IEEE 802.15.3a ultra-wideband
interface, and any combination of IEEE 802.11 a, b, g and/or n
interfaces. In a representative embodiment of the present
invention, the broadband access gateway 218 may comprise, for
example, a set top box that may be coupled in a wireless or wired
fashion to access devices such as, for example, a laptop computer
or television, such as the laptop 217 and the television 215 of
FIG. 2. Service may be provided to the home network 202a supported
by the broadband access gateway 218 via the cable modem 216, which
is coupled to the broadband access provider 206. The wireless
interface 220, the gateway 218 with modem 216, the BAP 206, the
GSM/EDGE/GPRS network 214, the transport network 232, and the CDMA
network 236 of FIG. 2 may correspond, for example, to the wireless
interface 120, the gateway 118 with modem 116, the BAP 106, the
GSM/EDGE/GPRS network 114, the transport network 110, and the CDMA
network 112, respectively, of FIG. 1.
[0034] The broadband access provider 206 may be, for example, a
cable company, telephone company (Telco), or an Internet service
provider (ISP). The broadband access provider 206 may utilize any
of the standardized formats such as DOCSIS, digital subscriber line
(DSL), or local multipoint distribution system (LMDS). LMDS
utilizes broadband wireless technology to deliver voice, video,
data, and/or Internet services utilizing licensed or unlicensed
spectrum in the frequency range of 25 GHz and higher. LMDS utilizes
point-to-point or point-to-multipoint communication to provide
broadband services, some of which rely on line of sight (LOS). LMDS
is a fixed wireless solution, and as such, no mobility support is
required.
[0035] The broadband access provider 206 may be also be a WiMAX or
Institute of Electrical and Electronics Engineers, Inc. (IEEE)
802.16-compliant service provider. The IEEE 802.16 standard offers
a wireless metropolitan area network (MAN) air interface which
provides network access to buildings via external antennas that
receive signals from a remotely located central base station. The
signal received at the building may be communicated to a wired
network infrastructure such as an IEEE 802.3 compliant
communication network, or a wireless network infrastructure such as
an IEEE 802.11a/b/g and/or n-compliant network. In instances where
WiMAX is utilized, then antenna 202b may be utilized to receive and
transmit signals between the broadband access provider 206 and the
home network 202a.
[0036] The WANs, PSTN, etc networks block 208 may comprise networks
such as private or public communication networks. For example, the
WANs, PSTN, etc networks block 208 may comprise a public switched
telephone network (PSTN) and a packet network such as a cellular
digital packet data (CDPD) network.
[0037] The content providers block 210 may comprise network
providers, which supply data and/or multimedia content. In a
representative embodiment of the present invention, the content
providers block 210 may comprise, for example, one or more mobile
virtual network operators (MVNOs). A MVNO is a mobile service
provider that provides mobile services to its subscribers by
utilizing the network infrastructure of another company. In this
regard, the MVNO enters into an agreement with a network operator
to purchase network time such as minutes, which it resells to it
own customers/subscribers. The MNVO utilizes the purchased time to
provide, for example, multimedia content delivery to its
subscribers.
[0038] The wireless service provider network 212 may, for example,
utilize CDMA, 3G or 4G access technology and may comprise a
plurality of cell sites. Cell site 212a may provide cellular
service to the mobile access device 228 while the mobile access
device 228 is within range of the cell site 212a. The wireless
service provider network 214 may, for example, utilize the time
division multiple access (TDMA) access technology of the GSM
standard, and may include enhanced data rates for GSM evolution
(EDGE) and/or general packet radio service (GPRS) data capability.
The wireless service provider network 214 may comprise a plurality
of cell sites and a wireless carrier central office 214b, the
latter of which may comprise a mobile switching center (MSC) 214g.
Cell site 214a may provide cellular service to mobile access device
226 while the mobile access device 226 is within range of the cell
site 214a.
[0039] Referring to FIG. 2, based on wireless performance
prediction parameters, a mobile access device such as, for example,
the mobile access device 226 may, for example, determine the QoS
that is being received from a serving communication network such as
the GSM/EDGE/GPRS network 214, for example. In addition, the mobile
access device 226 may sniff one or more portions of the radio
frequency (RF) spectrum and may detect one or more other wireless
communication networks. The mobile access device 226 may compare
the current QoS with the QoS that a newly sniffed communication
network such as, for example, the broadband access gateway 218 with
wireless interface 220 might provide. The newly sniffed network may
correspond to the home LAN 202a, for example. If wireless
performance prediction parameters such as, for example,
signal-to-noise ratio (SNR), fading characteristics (e.g., received
signal strength), communication error rates, and/or throughput
indicate that the newly sniffed communication network 202a would
provide a better QoS than the current serving communication network
214, then the mobile access device 226 may elect to switch from the
current serving communication network 214 to the newly sniffed
communication network 202a. However, if the wireless performance
prediction parameters indicate that the newly sniffed communication
network 202a would provide a lower QoS level than the current
serving communication network 214, then the mobile access device
226 may not initiate a switch from the current serving
communication network to the newly sniffed communication network
202a. In this regard, the mobile access device 226 may continue
receiving service from the current serving communication network
214 and also continue scanning to locate other compatible networks.
The decision to switch between or among wireless communication
networks may be initiated in silicon (i.e., by circuitry of the
access device 226), or it may be initiated from the application
layer.
[0040] In accordance with a representative embodiment of the
present invention, the mobile access device 226, for example, may
be currently receiving service via a first pathway from a wireless
service provider such as, for example, the GSM/EDGE/GPRS network
214. Although this example refers to receiving service, the service
may, for example, comprise either or both of receiving and sending
of multimedia information. As the mobile access device 226 moves
from network 214 towards network 202a, the mobile access device 226
may sniff a portion of radio frequency spectrum and may locate the
second communication network 202a, which may be accessible by, for
example, the broadband access gateway 218 of FIG. 2, a wireless
access point such as access point 207, for example, or a hot spot.
The wireless service provider (e.g., GSM/EDGE/GPRS network) 214 and
the second communication network 202a may, for example, occupy
separate portions of radio frequency spectrum and/or employ the
same or incompatible communication protocols. In response to
detecting the second communication network 202a, the mobile access
device 226 may determine from various parameters and attributes of
the signals of the second communication network 202a that the
mobile access device 226 would be provided with service at a higher
QoS level by the second communication network 202a, than that
provided by the current serving network, the wireless service
provider (e.g., GSM/EDGE/GPRS network) 214. Quality of service may
comprise, for example, error rates, frame rates, spatial
resolution, color depth, sample rates, levels of grey scale, bits
per sample, network delays, and the like.
[0041] In one representative embodiment of the present invention,
the mobile access device 226 and/or the current serving wireless
network, for example, may determine that the service provided by
the current serving wireless network (e.g., the GSM/EDGE/GPRS
network 214) is unable to support the bandwidth needed for the
exchange of multimedia information presently desired by the user of
the mobile access device 226. Using information such as, for
example, one or more of the wireless performance prediction
parameters described above, the mobile access device 226 and/or the
wireless network 214 may determine that communications conditions
only adequately support the exchange of multimedia information of a
lower resolution, bandwidth, or data rate. The term "lower
resolution" is used herein to refer to, for example, digitized
audio having fewer samples per second, fewer channels, or fewer
bits per sample. In a similar fashion, the term may also be used to
refer to digitized still image or video information having a lower
spatial resolution, fewer frames per second, lower number of grey
scale levels, and/or a reduced color depth. By reducing the
resolution of the exchanged multimedia information, and hence the
bandwidth or data rate needed for support, a representative
embodiment of the present invention is capable of maintaining
uninterrupted communication when encountering impairments of, for
example, the air interface. In a representative embodiment of the
present invention, a network entity such as, for example, the
wireless carrier central office 214b, the broadband access gateway
218, the access point 207, and/or the mobile access device 226 may
adjust, adapt, and/or modify the exchanged multimedia information
for communication over an impaired wireless communication channel
by changing the spatial resolution, number of grey scale levels,
color depth, frame rate, number of channels, sample rate, bits per
sample, for example. The selection of the form of modification may
be based upon user-defined parameters, rules, guidelines, and
limits that may be stored in a user-profile such as the user
profiles 219, 225, 235 shown in FIG. 2. In one representative
embodiment of the present invention, a user of an access device
such as, for example, the mobile access device 226 may be notified
of an automatic change in resolution of exchanged multimedia
information. In another representative embodiment, the user may be
prompted to select from options related to reducing the quality of
service provided, or identifying the additional bandwidth needed to
maintain communication at a level acceptable to the user.
[0042] In a representative embodiment of the present invention, a
mobile access device such as mobile access device 226, for example,
may determine that, due to changes in the air interface conditions,
a desirable quality of service level cannot be maintained by a
current serving wireless communication network such as the
GSM/EDGE/GPRS network 214, for example. Examples of such air
interface conditions may include high error rates caused by low
signal levels or signal-to-noise ratio (SNR), and fading, to name
only two. The mobile access device 226 may sniff radio frequency
spectrum with which it is compatible, and may detect additional
wireless communication networks such as the CDMA network 212, the
local/personal area network supported by the broadband access
gateway 218 with wireless interface 220, and the access point 207,
for example. In such a representative embodiment, elements of the
communication system 200 of FIG. 2 such as the wireless carrier
central office 214b, the broadband access gateway 218, the access
point 207, and the mobile access device 226, for example, may
enable simulcasting of multimedia information, to provide multiple
wireless communication paths. Although each of the individual paths
may not support sufficient throughput to enable communication at a
quality of service level acceptable to the user of the mobile
access device 226, the combined capacity may allow communication at
an acceptable QoS level. For example, in a representative
embodiment of the present invention, an access device such as, for
example, the mobile access device 226 may elect to establish
communication paths with a number of detected wireless
communication networks, and to "bounce" between service with the
wireless communication networks in order to create an aggregate
capacity that provides an acceptable quality of service to the
user.
[0043] In one representative embodiment of the present invention,
the user of the access device 226 may, for example, be notified
and/or prompted regarding the establishment of the additional
communication paths. Information about the cost of the additional
paths may be provided, and the option to reduce quality of service
or add communication paths may be provided to the user. Whether
such establishment is automatic, and the conditions under which the
paths are established and the user is notified and/or prompted may,
for example, be based upon parameter, guideline, rule, and/or limit
information residing in a user profile such as the user profiles
219, 225, 235 of FIG. 2.
[0044] During the periods when communication via a given path is
available, the mobile access device 226, the broadband access
gateway 218, the access point 207, and/or the GPS/EDGE/GPRS network
214, for example, may cache multimedia information to be used in
minimizing disruption of the multimedia stream to the recipient.
The amount of multimedia information may be beyond that normally
used when communicating via a non-impaired over-the-air link. The
mobile access device 226, the broadband access gateway 218, the
access point 207, and/or the wireless communication network 214 may
then assemble a properly sequenced, continuous stream of the
multimedia information using the portions received via each of the
multiple, simulcast paths. Sequencing information such as, for
example, packet sequence numbers or time stamps assigned to each
portion of multimedia information at the source may be used to
reassemble a properly sequenced stream at the receiving location.
This may enable the receipt via two or more paths of redundant
streams of multimedia information packets, which may then be
assembled into a continuous stream in which the redundant packets
have been eliminated.
[0045] In a representative embodiment of the present invention, the
bouncing between multiple wireless communication paths may be
adjusted to be compatible with the form of multimedia information
being exchanged. For example, some forms of multimedia information
such as, for example, Moving Picture Experts Group (MPEG) video and
audio streams contain reference frames (e.g., I-frames or
I-pictures) that are normally used as anchor frames upon which the
display of multiple other frames depend. Loss or corruption of such
anchor frames may be expected to cause a greater degree of
impairment in the exchange and consumption of such types of
multimedia information, than the loss of other frames in the
multimedia information stream (e.g., MPEG P or B-frames). In a
representative embodiment of the present invention, the timing of
bouncing between multiple wireless communication paths may be
based, at least in part, upon the detection of such reference
information or synchronization events in a stream of multimedia
information. For example, any of the mobile access device 226, the
broadband access gateway 218, the access point 207, and/or the
GPS/EDGE/GPRS network 214 of FIG. 2 may analyze a multimedia
information stream and may introduce hysteresis in the bouncing
behavior of a representative embodiment of the present invention,
based upon the detection of synchronization events such as those
described above. By adjusting the points in time when bouncing
between networks takes place, and the amount of multimedia
information that is cached, the impact of an impaired over-the-air
link may be minimized, and throughput may be maximized.
[0046] In a representative embodiment of the present invention, a
mobile access device such as, for example, the mobile access device
226 of FIG. 2 may bounce between multiple wireless networks like
the GSM/EDGE/GPRS network 214 and local area network of access
point 207 of FIG. 2, for example. The bouncing may take into
account the nature of the multimedia information being exchanged.
In a representative embodiment of the present invention, the
bandwidth available via each of the wireless networks may be
different, and full redundancy of packet exchange via all available
paths may not be used. As conditions improve on any path, more
multimedia information may be exchanged via that path, while still
maintaining other paths. During an exchange of MPEG encoded video,
I-pictures that are used as anchor information in image prediction
may be detected and specifically selected for exchange over the
most reliable wireless network, since their loss or corruption may
have significant and lasting effects on the displayed image. The
bouncing between networks may also be restricted when such
significant events are detected in the multimedia information
stream, whether it be video, audio, or other digital
information.
[0047] In another representative embodiment in accordance with the
present invention, the mobile access device 226 may determine from
wireless performance prediction parameters or attributes that
certain modes or forms of multimedia communication cannot be
supported, due to a lack of communication bandwidth. This
determination may follow attempts to establish additional wireless
communication paths, or an automatic or user decision not to
establish the additional wireless communication paths involved in
supporting multimedia communication. For example, a user of an
access device such as, for example, the mobile access device 226 of
FIG. 2 may migrate over the coverage area of a serving wireless
service such as the GSM/EDGE/GPS network 214, and may enter an area
in which network conditions do not support multimedia communication
at a certain user-defined quality of service level (e.g., a
particular spatial resolution, color depth, and frame rate). The
user of the mobile access device wish to engage in a multimedia
communication session, and additional communication paths may not
be available and/or capable of providing the bandwidth needed to
continue the current level of service. In a representative
embodiment of the present invention, the user may be limited to
certain forms of multimedia communication such as, for example,
text communication. In other representative embodiments of the
present invention, a network element such as, for example, the
broadband access gateway 218 and/or the wireless carrier central
office 214b, shown in FIG. 2, may adjust the encoding of the
multimedia information to reduce the bandwidth that is required.
For example, a broadband access gateway or wireless wide area
network may transcode one information stream to form another of
lower bit rate, or may convert a multimedia information stream from
one encoding standard into another. A representative embodiment of
the present invention may also strip higher bandwidth components
such as, for example, a video stream, from a multimedia information
stream also containing textual information, and may pass only the
textual information, if conditions of the available wireless
networks preclude the exchange at the higher bandwidth.
[0048] FIG. 3A shows an exemplary display 300 of a wireless access
device that may correspond to, for example, the wireless access
device 226 of FIG. 2 upon encountering wireless network
impairments, in accordance with a representative embodiment of the
present invention. The display 300 of FIG. 3A comprises a network
indicator 310, a network services indicator area 312, a battery
life indicator, a time of day indicator, and a day and date
indicator. In addition, in the example of FIG. 3A, the network
services indicator area 312 has been updated to comprise an
Internet protocol (IP) phone service icon 315, a printer service
icon 316, a stereo entertainment icon 317, a pay music service icon
318, a video entertainment icon 319, and a storage service icon 320
showing those services advertised by the wireless broadband access
gateway as being available. The display 300 also comprises a
display area 322 to allow an access device to present graphical or
textual information for a variety of reasons and from a number of
sources. In the illustration of FIG. 3A, the mobile access device
has displayed information 340 indicating that the current network
serving the call is unable to support the QoS desired by the user.
This may occur when, for example, wireless network load, received
signal strength, signal to noise ratio, or error rate is such that
the wireless interface can no longer carry sufficient bandwidth to
support the mode of communication (e.g., speech, still image,
music, video). The display area 322 also comprises a notice 342
that an additional wireless network, in this example a WiFi (IEEE
802.11) network, has been found and added as a call path. In this
case, the user is informed that the additional capacity is
available via a no-cost (e.g., public) wireless network. The types
of wireless networks that may be eligible for use may be defined
by, for example, parameters, guidelines, rules, and/or limits
stored in a user profile such as the user profiles 219, 225, 235
shown in FIG. 2. In the example of FIG. 3A, the additional network
is joined to the call automatically, although in other
representative embodiments the user may be prompted for a response
indicating approval or selection of additional capacity.
[0049] FIG. 3B shows another exemplary display 300 of a wireless
access device that may correspond to, for example, the wireless
access device 226 of FIG. 2 upon encountering wireless network
impairments in which a user is prompted to choose a remedy, in
accordance with a representative embodiment of the present
invention. The display 300 of FIG. 3B comprises a network indicator
310, a network services indicator area 312, a battery life
indicator, a time of day indicator, and a day and date indicator.
In addition, in the example of FIG. 3B, the network services
indicator area 312 has been updated to comprise an Internet
protocol (IP) phone service icon 315, a printer service icon 316, a
stereo entertainment icon 317, a pay music service icon 318, a
video entertainment icon 319, and a storage service icon 320
showing those services advertised by the wireless broadband access
gateway as being available. The display 300 also comprises a
display area 322 to allow an access device to present graphical or
textual information for a variety of reasons and from a number of
sources. The display area 322 shown in the illustration of FIG. 3B
displays information 340 indicating that the current network
serving the call is unable to support the QoS desired by the user.
As previously described, this may be caused by a number of factors
including, for example, wireless network load, received signal
strength, signal to noise ratio, or error rate. In the illustration
of FIG. 3B, the display area 322 also comprises a prompt 342
offering options the user may select to remedy impact that network
conditions may have upon the multimedia information exchange. In
this example, the user is informed that option 1 344 may be
selected to purchase additional capacity for $0.03 per minute, and
that option 2 346 may be selected to reduce the quality of the
multimedia exchange and avoid additional cost. The conditions under
which a user is prompted may be determined by, for example,
parameters, guidelines, rules, and/or limits stored in a user
profile such as the user profiles 219, 225, 235 shown in FIG. 2.
Although the example of FIG. 3B shows a particular arrangement of
text, other forms of user interface may be employed without
departing from the spirit and scope of the present invention. When
conditions improve, or additional bandwidth becomes available, a
representative embodiment of the present invention may resume the
exchange of multimedia information at a higher QoS by including
previously stripped or restricted content.
[0050] FIG. 4 shows an exemplary display 400 of a wireless access
device that may correspond to, for example, the wireless access
device 226 of FIG. 2 following a user attempt to engage in a
multimedia exchange while in a service area subject to wireless
network impairments, in accordance with a representative embodiment
of the present invention. The display 400 of FIG. 4 comprises a
network indicator 410, a network services indicator area 412, a
battery life indicator, a time of day indicator, and a day and date
indicator. In addition, in the example of FIG. 4, the network
services indicator area 412 has been updated to comprise an
Internet protocol (IP) phone service icon 415, a printer service
icon 416, a stereo entertainment icon 417, a pay music service icon
418, a video entertainment icon 419, and a storage service icon 420
showing those services advertised by the wireless broadband access
gateway as being available. The display 400 also comprises a
display area 422 to allow an access device to present graphical or
textual information for a variety of reasons and from a number of
sources. The mobile access device of the illustration of FIG. 4 has
displayed information 440 indicating that the multimedia service
requested by the user is currently unavailable due to network
conditions, and has offered the user a voice option 442, a text
messaging option 444, and a still image option 446. Restrictions in
the exchange of multimedia information and service access may occur
when wireless network load, receive signal strength,
signal-to-noise ratio, and/or error rate, for example, precludes
support in accordance with the QoS defined by the user. Parameters,
guidelines, rules, and/or limits defined by the user and stored in
a user profile such as the user profiles 219, 225, 235 of FIG. 2,
for example, may be applied to determine the types of wireless
network that are made available under specific wireless network
conditions.
[0051] FIGS. 5A and 5B show message exchange diagrams that
illustrate the use of background network scanning in the
association of a mobile access device that may correspond to the
mobile access device 226 of FIG. 2 with wireless networks during
the establishment and progression through an exemplary multimedia
information exchange, in accordance with a representative
embodiment of the present invention. In the illustration of FIGS.
5A and 5B, the four vertical lines represent a wireless wide area
network 502, a mobile access device 504, a wireless local/personal
area network #1 506, and a wireless local/personal area network #2
508 that may correspond to, for example, the GSM/EDGE/GPRS network
214, the mobile access device 226, and the wireless network
supported by the broadband access gateway 218 with wireless
interface 220, and the access point 207, respectively, of FIG. 2.
The horizontal lines of FIGS. 5A and 5B represent message traffic
or groups of messages exchanged between a source and a destination,
the destination being indicated by the arrow head. The vertical
dimension represents time, advancing downward on the message
exchange diagrams 500.
[0052] In a representative embodiment of the present invention, the
mobile access device 504 may initiate an exchange of multimedia
information via the wireless wide area network 502 using messaging
510, 512 with any of several network entities including, for
example, another mobile access device served by the wireless wide
area network 502, or a party accessible via the transport network
232 of FIG. 2 such as, for example, the content provider 210.
Although this example describes the initiation of an exchange by
the mobile access device 504, a similar sequence of events within
the spirit and scope of the present invention may be applied to
exchanges involving the mobile access device 504 that are initiated
by other than the mobile access device 504. The messaging 510, 512
may comprise multiple messages for establishing communication
between the mobile access device 504 and the wireless wide area
network 502. In the illustration of FIG. 5A, the wireless wide area
network 502 may activate path 514 and may use the path 514 to
transport multimedia information between the wireless wide area
network 502 and the mobile access device 504. The mobile access
device 504 may then enable background network scanning
functionality 515, to detect the presence of compatible wireless
networks, and to determine wireless performance prediction
parameters for the currently active and detected wireless networks.
In a representative embodiment of the present invention, scanning
may comprise sniffing of radio frequency spectrum.
[0053] At a later time in the information exchange, the mobile
access device 504 may migrate to within the coverage area of a
wireless service provider such as, for example, the wireless
local/personal area network #1 506 that may correspond to, for
example, the broadband access gateway 218 with wireless interface
220, of FIG. 2. At some later time, the background network scanning
functionality 517 of the mobile access device 504 may detect the
presence of signals 516 from the wireless local/personal area
network #1 506, may analyze the received signals, and may determine
that the wireless local/personal area network #1 506 may be
employed with the mobile access device 504 during multimedia
exchanges. This determination may be performed entirely within the
mobile access device 504, or it may involve interaction with other
network entities such as, for example, the wireless carrier central
office 214b, the central control and management function 248, or
entities accessible via the transport network 232, for example. At
this point in the communication session, the service received via
the wireless wide area network 502 may satisfactorily support the
exchange of multimedia at the QoS desired by the user, as indicated
in a user profile such as the user profiles 219, 225, 235 of FIG.
2, for example.
[0054] Later, the network conditions of wireless wide area network
502 may change 521 due to impairments such as, for example,
interference, reduced signal strength, network loading, and/or
other causes. This may prompt the evaluation 522 of the available
wireless networks for the communication of the multimedia
information. In one representative embodiment of the present
invention, the mobile access device 504 may identify network
capacity in addition to that provided by the wireless wide area
network 502, using information about the wireless networks detected
by the background network scanning functionality 517 of the mobile
access device 504, and a user profile comprising, for example,
parameters, guidelines, rules, and/or limits related to the QoS
desired by the user. In one representative embodiment of the
present invention, the evaluation may result in the automatic
selection of the wireless local/personal area network #1 506 to add
sufficient capacity to completely support the desired multimedia
exchange. The mobile access device may then begin exchanging
multimedia information via both the wireless wide area network 502
and the wireless local/personal area network #1 506 using, for
example, messaging 524, 526a, 526b.
[0055] The user communication session may continue for some time,
and the user may migrate within the coverage area of the wireless
local/personal area network #2 508. The background network scanning
functionality 530 of the mobile access device may detect the
signals 528 of the wireless local/personal area network #2 508, may
analyze the received signals, and may determine that the wireless
local/personal area network #2 508 may also be employed with the
mobile access device 504 during the exchange of multimedia
information. The wireless network service provided by wireless wide
area network 502 and the wireless local/personal area network #1
506 may then change 532 as the user moves or other sources of
impairment become apparent, and may degrade to the point where none
of the communication paths is reliable enough, as shown by
messaging 534, 536a, 536b, 538, 540. Failures of messaging are
shown in FIG. 5A by an "X" terminating a message path. At some
point, the aggregate capacity of the wireless wide area network 502
and the wireless local/personal area network #1 506 may no longer
be sufficient to support the desired multimedia information
exchange. This may again prompt the evaluation 542 of the wireless
networks available for the communication of the multimedia
information, as described above, and the recently sniffed wireless
local/personal area network #2 508 may be added to the set of
communication paths, shown by messaging 544, 546a, 546b, 548a,
548b. In this example, three wireless network paths are now in use
to support the multimedia exchange. A representative embodiment of
the present invention, however, is not limited in respect, as a
greater number of communication paths may be employed.
[0056] Continuing with respect to the illustration of FIG. 5B,
network conditions may continue to change 550 and may degrade such
that the exchange of multimedia information at the desired QoS can
no longer be supported. In one representative embodiment in
accordance with the present invention, the mobile access device may
determine the options available 552 to maintain the multimedia
exchange, within the conditions defined by user defined parameters,
guidelines, rules, and/or limits contained in a user profile, as
described above. Because no additional wireless network capacity
has been detected by the background network scanning functionality
530 of the mobile access device 226, the mobile access device 504
may determine that a reduction in the QoS is an option. In a
representative embodiment of the present invention such as that
shown in FIG. 5B, the user may be prompted with a query 554
providing options that may be selected. For example, in order to
maintain communication, the user may agree to reductions in image
spatial resolution, color depth, a frame rate, audio quality (e.g.,
bits per sample, samples per second, number of audio channels, type
of compression used), or to strip unsupportable components of a
multimedia stream. In one representative embodiment of the present
invention, a network entity such as, for example, the wireless
carrier central office 214b of FIG. 2 may begin adjusting 556 the
format of the multimedia information content, performing operations
such as, for example, transcoding, changing compression algorithms,
and/or reducing spatial and/or color resolution, frame rates,
and/or number of bits per pixel or audio sample. The resulting
multimedia stream may, after such format adjustment 556 comprise
only voice, text, or simple still image graphics, for example. The
resulting reduced-bandwidth information stream may be exchanged via
the now, much degraded wireless network paths described above,
using messaging 558, 560a, 560b, 562, 564a, 564b, 566, 568. By
adding wireless network capacity, bouncing between impaired
networks, or reducing the quality of service level to be provided
to the user, in accordance with user-defined parameters, rules,
guidelines, and/or limits, a representative embodiment of the
present invention is able to maintain communication at some level,
where conventional communication arrangements may simply end the
call.
[0057] In some representative embodiments of the present invention,
the selection of action to maintain the multimedia communication
session may be performed automatically, without involving the user.
The selection of the most suitable option may be based upon a
profile of user defined parameters, rules, guidelines, and/or
limits that are relevant to maintaining a particular minimum
quality of service (QoS) level desired by the user. The user
profile may include one or more of such items as cost of bandwidth
in bits-per-second, cost per minute/packet/bytes exchanged, spatial
resolution of images or video, color depth, frame rates, audio
channels and perceived quality, network delay, information
security, compression algorithms used, etc., to name only a few
items.
[0058] In other representative embodiments in accordance with the
present invention, the selection of the action taken to maintain
multimedia communications session may involve user notification of
the user of possible options, and evaluation and selection of one
of the indicated options. Involvement of the user in the
communication options may be employed when, for example, a
particular set of network conditions lies outside of the conditions
addressed by the parameters, guidelines, rules, and/or limits
defined in a user profile. In other cases, prompting of the user
may be performed when network conditions are within those in which
the user wishes to be involved.
[0059] FIG. 6 is a flowchart illustrating an exemplary method of
supporting association of a mobile access device such as, for
example, the mobile access device 224 of FIG. 2 using background
network scanning, in accordance with a representative embodiment of
the present invention. As an aid to understanding the method of
FIG. 6, the following description makes reference to elements of
FIG. 2. The method of FIG. 6 begins with a mobile access device
such as, for example, the mobile access device 224 in an idle state
(block 610). At some point, the user of the mobile access device
224 elects to initiate or accept the establishment of a
communication path or channel for the exchange of multimedia
information (block 612). This may result from the placing or
acceptance of a call involving multimedia information, or an
attempt to access a source of multimedia information via, for
example, a wireless wide area network such as the GSM/EDGE/GPRS
network 214 of FIG. 2. The flowchart of FIG. 6 shows that following
establishment of the communication path, the mobile access device
224 may commence scanning portions of the radio frequency spectrum
with which it is compatible (block 614), to determine whether other
networks may be available. Another representative embodiment of the
present invention may begin scanning immediately after power-up, to
enable the mobile access device to have ongoing knowledge of all
available wireless network resources should network communication
be desired.
[0060] Next, a determination is made whether a new network has been
detected (block 616). If a new network has been detected,
characteristics of the network such as, for example, the frequency
of operation, protocol in use, protocol operating parameters, and
other information are determined (block 618). This may involve
analysis by the mobile handset 224 of the received wireless network
signals, and may employ network resources such as, for example, the
wireless carrier central office 214b, the central control and
management function 248, or other network-based entities accessible
via the transport network 210, to determine the nature and secure
authorization for access to the detected wireless network. If no
new wireless network is detected, or after the characteristics of a
newly detected network are determined, a determination may be made
whether the wireless network paths currently available to the
mobile access device 244 are sufficient to meet the quality of
service (QoS) desired the user (block 620). If the wireless network
paths currently available to the mobile access device 244 are
sufficient to meet the desired QoS (block 620), the method of FIG.
6 uses the currently available wireless networks for any exchange
of multimedia information (block 622). A check is then made whether
call communication has ended (block 624), and is so, the method of
FIG. 6 ends (block 642). If the call has not ended, the method
loops back to check whether a new wireless network resource has
been detected (block 616).
[0061] If the mobile access device determines that the currently
available wireless networks are not meeting the desired QoS (block
620), the mobile access device may determine what options are
available (block 626). This may involve accessing a user profile on
the mobile access device 224 such as user profile 225, for example,
or in an accessible network entity such as the user profiles 219,
235 shown in FIG. 2. In the representative embodiment of the
present invention of FIG. 6, the user may be notified of the
network difficulties (block 628), and a determination (e.g., based
on a user profile) may be made whether the user is to be queried
for input on selection of an option (block 630). The determination
may use, for example, information in a user profile or service
provider option. If a user prompt is indicated, the user of the
mobile access device 224 is prompted (block 632). If no user prompt
is to be performed, or after the user responds with a selection if
a prompt was performed, the method of FIG. 6 determines whether
additional wireless network capacity is to be added to the set of
current network paths used for call communication (block 634). If
additional network capacity is not permitted, the method shown in
FIG. 6 may attempt to remedy the decline in QoS by adjusting mobile
access device operation to maximize QoS and maintain the call
communication by adjusting the bandwidth needed to support the call
(block 640). This may include transcoding to lower bit rates,
selecting an alternate protocol and/or compression algorithm,
reducing a frame rate and/or a spatial or color resolution, or
completely stripping some multimedia components from the call
communication, for example.
[0062] If the addition of further wireless network capacity is
permitted, a determination is made as to whether there is
additional wireless network capacity available (block 636). If no
additional capacity is available, the method may attempt to remedy
the decline in QoS by adjusting mobile access device operation to
maximize QoS and maintain the call communication by adjusting the
bandwidth needed to support the call (block 640), as described
above. If additional capacity is available, the mobile access
device 224 may establish or use additional path(s) for the exchange
of multimedia information (block 638), employing those network
paths detected by the background network scanning functionality
described above. Adding capacity may include, for example, adding
new wireless networks to the paths used for communication, and
authorizing payment for additional costs for additional capacity on
wireless networks that may already be part of the call
communication. Once the additional capacity has been made
available, the method begins using the currently available set of
paths for call communication.
[0063] In various representative embodiments of the present
invention, use of the current wireless network path(s) for the
exchange of multimedia information may include, for example,
simulcasting of the information over two or more wireless network
paths. For example, if several wireless network paths are
available, but none has sufficient capacity to carry the entire
multimedia information stream reliably, the stream may be simulcast
over all available wireless network paths, and reassembled into a
single stream at the receiver. This may be accomplished using, for
example, sequence numbering of packets or time stamp information.
When a number of wireless networks are in available at no or low
cost, simulcasting may be used over disparate networks to improve
reliability and capacity at little cost to the user.
[0064] In a representative embodiment of the present invention, the
wireless networks used for the communication of multimedia
information may, for example, employ different portions of the RF
spectrum, and use different air interfaces and different
communications protocols.
[0065] In some representative embodiments of the present invention,
communication of multimedia information may bounce among a number
of wireless networks, as the condition of each of the wireless
networks improves and degrades. For example, if a number of
wireless networks are in use, and each the user incurs charges for
according to amount of information sent or passed via the wireless
network, it may be more cost effective if the communication of
multimedia information bounces between wireless networks as
conditions change. This may be especially useful when wireless
network conditions are changing, but sufficient periods of
satisfactory wireless network performance occur over a number of
wireless networks having the aggregate throughput needed to support
the desired quality of service.
[0066] In a representative embodiment of the present invention,
when wireless network capacity has been exhausted, or user
preferences restrict the addition of capacity to a call, the
multimedia information being exchanged may be modified to reduce
the bandwidth needed. For example, changes in protocol used for
communicating audio, still images, video, etc., may be made to
reduce the amount of data exchanged to within the capacity of the
available wireless communication paths. A mobile access device, and
network entities such as, for example, a wireless carrier central
office, a broadband access gateway, an access point, or other
network entities may adapt or adjust the information being
exchanged, by reducing spatial or color resolution, the number of
frames or samples per unit time, the number of bits per pixel or
sample, the number of channels of audio, video, or data, for
example. This may also include the stripping, elimination, or
redirection of some components of a multimedia stream, in order to
allow the call to be maintained in a manner that conforms with the
desires of the user.
[0067] Aspects of the present invention may be found in a method
supporting quality of service based association of a mobile access
device with a new wireless communication network using background
network scanning. Such a method may comprise establishing
communication via a first wireless network, detecting at least a
second wireless network by scanning radio frequency spectrum, and
determining at least one characteristic of the at least a second
wireless network. The method may also comprise identifying network
capacity among the first wireless network and the at least a second
wireless network sufficient for exchange of multimedia information,
and exchanging multimedia information using identified network
capacity. In addition, the method may comprise detecting
insufficient capacity for exchange of the multimedia information,
and adjusting communication of multimedia information according to
at least one user-defined quality of service parameter.
[0068] In a representative embodiment of the present invention, the
first and the at least a second wireless network may comprise one
of: a wireless wide area network, a wireless local area network,
and a personal area network, and the wireless local area network
may comprise one of: an Institute of Electrical and Electronics
Engineers (IEEE) 802.11 protocol and an IEEE 802.15.3a protocol.
The at least one characteristic may comprise one of: a radio
frequency, an air interface protocol, a bandwidth, and a parameter
used for network access. The air interface protocol may comprise
one of: a time division multiple access (TDMA) protocol and a code
division multiple access (CDMA) protocol, and multimedia
information may comprise one of: streaming video, broadcast video,
voice, digital data, text, digitized audio, digitized still images,
digitized video, and digitized music.
[0069] In a representative embodiment of the present invention,
adjusting communication of multimedia information may comprise
identifying additional network capacity for communication of the
multimedia information, from the at least a second wireless
network. The additional network capacity may be on a wireless
network different from those previously identified. Adjusting
communication of multimedia information may comprise one of:
changing a protocol used to represent the multimedia information,
transcoding the multimedia information, and changing a resolution
of the multimedia information, and exchanging multimedia
information may comprise concurrently exchanging the multimedia
information using the first wireless network and the at least one
second wireless network. Exchanging multimedia information may
comprise individually exchanging portions of the multimedia
information using each of the first wireless network and the at
least a second wireless network. The first wireless network and the
at least a second wireless network may employ different air
interface protocols, and scanning may comprise sniffing of radio
frequency spectrum.
[0070] Other aspects of the present invention may be seen in a
mobile access device supporting exchange of multimedia information
employing quality of service based association with a new network
using background network scanning. A representative embodiment of
the present invention may comprise at least one wireless interface
capable of exchanging multimedia information with a first wireless
network while scanning radio frequency spectrum to detect at least
a second wireless network. The first wireless network may support a
first network capacity for exchange of multimedia information and
the at least a second wireless network may support at least a
second network capacity for exchange of multimedia information. A
representative embodiment of the present invention may also
comprise storage comprising at least one user-defined criteria
employed in selecting wireless networks for exchange of multimedia
information. The device may also comprise software resident in
memory of the device, the software executable for determining at
least one characteristic of the at least a second wireless network,
and for identifying network capacity among the first wireless
network and the at least a second wireless network sufficient for
exchange of multimedia information. The device may be capable of
adjusting communication of multimedia information based upon the at
least one user-defined criteria and the identified network
capacity.
[0071] In a representative embodiment of the present invention, the
first and the at least a second wireless network comprise one of: a
wireless wide area network, a wireless local area network, and a
personal area network, where the wireless local area network may
comprise one of: an Institute of Electrical and Electronics
Engineers (IEEE) 802.11 protocol and an IEEE 802.15.3a protocol.
The at least one characteristic may comprise one of: a radio
frequency, an air interface protocol, a bandwidth, and a parameter
used for network access, and the air interface protocol may
comprise one of: a time division multiple access (TDMA) protocol
and a code division multiple access (CDMA) protocol. Multimedia
information may comprise one of: streaming video, broadcast video,
voice, digital data, text, digitized audio, digitized still images,
digitized video, and digitized music.
[0072] In a representative embodiment of the present invention,
adjusting communication of multimedia information may comprise
identifying additional network capacity for communication of the
multimedia information, from the at least a second wireless
network. The additional network capacity may be on a wireless
network different from those previously identified. Adjusting
communication of multimedia information may comprise one of:
changing a protocol used to represent the multimedia information,
transcoding the multimedia information, and changing a resolution
of the multimedia information. Exchanging multimedia information
may comprise concurrently exchanging the multimedia information
using the first wireless network and the at least one second
wireless network, exchanging multimedia information may comprise
individually exchanging portions of the multimedia information
using each of the first wireless network and the at least a second
wireless network. The first wireless network and the at least a
second wireless network may employ different air interface
protocols, and scanning may comprise sniffing of radio frequency
spectrum.
[0073] In a representative embodiment of the present invention, the
wireless local area networks may include data networks such as, for
example, Institute of Electrical and Electronics Engineer (IEEE)
802.11a/b/g/n compliant wireless networks such as those located in
homes, hot spots or an office. Such local area networks may operate
in unlicensed radio frequency spectrum such as in, for example, the
2.4 and 5-gigahertz regions. Examples of wide area networks may
include cellular digital packet data (CDPD), voice and data
networks such as public switched telephone networks (PSTN), Global
System For Mobile Communication (GSM), GSM General Packet Radio
Service (GPRS), GSM Short Message Service (SMS), GSM Enhanced Data
Rates For Global Evolution (EDGE), North American Time Division
Multiplex Access (TDMA), iDEN, Code Division Multiple Access (CDMA)
and CDMA2000 1xRT, Universal Mobile Telecommunications System
(UMTS) network, to name only a few.
[0074] A personal area network (PAN) may be formed by a plurality
of wireless communication access devices such as, for example,
mobile multimedia handsets, PDAs, telephones, and computers. Other
elements of such a network may, for example, include computer
peripherals such as digital scanners, digital cameras, printers,
headphones, and pointing devices, that may be located within the
immediate proximity of a person. A PAN may be an ad-hoc network of
such communication devices. In a representative embodiment of the
present invention, access devices within the PAN may communicate
with other access devices within the PAN and also with other access
devices that are located in other networks accessible via the PAN.
The personal area networks may include data networks such as, for
example, a Bluetooth compliant network, and Institute of Electrical
and Electronics Engineers (IEEE) 802.15.3a compliant wireless
networks. Such personal area networks may operate in unlicensed
radio frequency spectrum such as, for example, the 2.4 and
5-gigahertz regions. Details of one example of a personal area
network are provided in the document "Bluetooth Core Specification
V1.2", Nov. 5, 2003, from Bluetooth SIG, Inc., the complete subject
matter of which is hereby incorporated herein by reference, in its
entirety. For example, in a Bluetooth.RTM. wireless PAN, a first
Bluetooth.RTM.-enabled wireless access device may communicate with
a second Bluetooth.RTM.-enabled wireless access device within the
PAN. Additionally, either of the first and second
Bluetooth.RTM.-enabled wireless access devices may communicate with
the Internet or another LAN or WAN via the Bluetooth.RTM. wireless
PAN.
[0075] In a representative embodiment of the present invention, a
gateway may be adapted to provide seamless and transparent
communication between a plurality of access devices and a plurality
of networks. The functionality of the gateway may be divided, for
example, into application content functionality, and configuration
and management functionality. The application content functionality
may, for example, deal with the types of applications that may be
supported by the gateway as well as the various types of data that
may be received, processed and/or transmitted by the gateway. In
this regard, application content functionality may also include the
manner in which other devices and/or systems may utilize data from
the gateway.
[0076] Content and application services are considerations because
all the information coming into and leaving the home from either
the WAN side (i.e., the broadband connection side), or from the PAN
side (i.e., the access device side) converges at the gateway. The
PAN side may comprise Bluetooth, wireless LAN (IEEE 802.11
a/b/g/n), IEEE 802.15.3a ultra-wideband, or cellular, for example.
Notwithstanding, the gateway may be adapted to convert, for
example, wirelessly received GSM-formatted information into, for
example, Internet protocol (IP)-formatted information and in
reverse, converts IP-formatted information into wireless
GSM-formatted information suitable for over-the-air transmission.
Support for other wireless communication protocols such as TDMA,
CDMA, and UMTS may also be provided. In a representative embodiment
of the present invention, the gateway may comprise suitable
circuitry, logic and/or code that may be adapted to receive and
process MPEG related data, which may be suitable for display on a
screen. The gateway in an embodiment of the present invention
functions as a focal point where data converges from a plurality of
wired and wireless services. Although, in a particular embodiment
of the present invention the gateway may do very little in terms of
actual content aggregation, there is virtual aggregation of data.
The converged data may be integrated and or otherwise utilized to
offer unique opportunities for launching various content and
application services from a single strategic location. Since the
gateway in an embodiment of the present invention is the focal
point where data converges, one or more protocol stacks may be
employed for launching the various content and application
services.
[0077] The gateway in a representative embodiment of the present
invention may be adapted to route calls based on established rules
that may be programmed into the gateway. For example, the gateway
may be governed by a rule which states that local calls are to be
routed to an incumbent local exchange carrier (iLEC), while long
distance calls are to be handled by Long Distance Carrier Company.
Accordingly, when a call originates at the gateway and it is
determined that the call is a local call, the gateway may be
adapted to route the call to the iLEC. However, if the gateway
determines that the call is a long distance call, then the gateway
may be adapted to route the call to Long Distance Carrier
Company.
[0078] A representative embodiment of the present invention may
leverage existing broadband infrastructure that is commonly found
in many homes and businesses today. Because a consumer is already
paying for the use of the broadband infrastructure in their home or
office, leveraging the use of the existing broadband infrastructure
for communication with wide area networks results in minimal or no
communication costs. The broadband infrastructure may be, for
example, a cable or DSL infrastructure.
[0079] The wireless interface function provided by the gateway
located within a home, for example, may be utilized to route or
communicate a great deal of traffic to a wired network such as a
broadband network or a wireless network such as a GSM or CDMA
network via a broadband connection. In other words, the wireless
gateway infrastructure provided by a representative embodiment of
the present invention provides a scalable network infrastructure
that rides on an existing access infrastructure already supplied by
a broadband service provider to a home, office or business.
Additionally, the scalable infrastructure provided by the gateway
also solves the problems associated with signal penetration and
propagation, thereby providing improved quality of service (QoS).
From a market perspective, a wireless service provider may now have
access to the necessary infrastructure to provide improved wireless
services to users within a home or office. Accordingly, in order to
rapidly increase their growth, wireless service providers may now
target that portion of the in-home landline or plain old telephone
system (POTS) business, which have traditionally been handled by
incumbent local exchange carriers (ILECs) or other LECs.
[0080] The unlicensed mobile access gateway described above may
possess a significant amount of processing power. The gateways of
existing systems fall short of realizing the full potential of the
merged wired and wireless communication network that is enabled by
a representative embodiment of the present invention. Numerous
basic and enhanced communication services may be enabled or
provided by the gateway. Support for access devices such as, for
example, mobile multimedia handsets and PDAs may be involved in
order to utilize these basic and enhanced communication services
enabled by the new wave of digital technologies. Current and/or
proposed mobile access gateway systems, however, do not provide the
range of support needed for their use by the everyday consumer.
[0081] In a representative embodiment of the present invention, an
access device such as, for example, a mobile multimedia handset
engaged in a call served by a wireless wide area network may
migrate to within the coverage area of an associated broadband
access gateway with a wireless interface. The wireless wide area
network may simulcast call content to the broadband access gateway
via a broadband network. A user in the proximity of the broadband
access gateway may be notified of the simulcasting of the call, and
may elect to continue the call via a cordless phone or other access
device that is compatible with the wired and/or wireless interfaces
of the broadband access gateway.
[0082] Accordingly, the present invention may be realized in
hardware, software, or a combination of hardware and software. The
present invention may be realized in a centralized fashion in at
least one computer system, or in a distributed fashion where
different elements are spread across several interconnected
computer systems. Any kind of computer system or other apparatus
adapted for carrying out the methods described herein is suited. A
typical combination of hardware and software may be a
general-purpose computer system with a computer program that, when
being loaded and executed, controls the computer system such that
it carries out the methods described herein.
[0083] The present invention may also be embedded in a computer
program product, which comprises all the features enabling the
implementation of the methods described herein, and which when
loaded in a computer system is able to carry out these methods.
Computer program in the present context means any expression, in
any language, code or notation, of a set of instructions intended
to cause a system having an information processing capability to
perform a particular function either directly or after either or
both of the following: a) conversion to another language, code or
notation; b) reproduction in a different material form.
[0084] While the present invention has been described with
reference to certain embodiments, it will be understood by those
skilled in the art that various changes may be made and equivalents
may be substituted without departing from the scope of the present
invention. In addition, many modifications may be made to adapt a
particular situation or material to the teachings of the present
invention without departing from its scope. Therefore, it is
intended that the present invention not be limited to the
particular embodiment disclosed, but that the present invention
will include all embodiments falling within the scope of the
appended claims.
* * * * *