Note: Descriptions are shown in the official language in which they were submitted.
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FILE SHARING VIA LINK GENERATION
TECHNICAL FIELD
[0001] The disclosed embodiments relate generally to sharing of data over a
network. In particular, the disclosed embodiments are directed to sharing of
user files
via user-generated links.
BACKGROUND
[0002] It is now common for an individual to regularly use multiple
computers from
multiple different locations. A typical user may have a first computer at the
office and a
second computer at home, for example, as well as a portable computer, and a
web-
enabled mobile device such as a smartphone. To have ready access to the user's
content, it is desirable for the user to share his files between these
multiple computers.
[0003] One way to share files between these multiple computers is to
manually
transfer the files from one to the other¨for example, a user may e-mail
himself a copy
of a file he is working on before leaving the office, so that he can resume
working on it
later from home. If the user forgets to e-mail or bring the file home with
him, he must
either go back to the office to retrieve it, or perhaps simply wait until the
next day.
Alternatively the user can attempt to remotely access to his work computer,
for example
using a virtual private network (VPN) to access a corporate network from a
remote
location, but only if such access is authorized. However, if the user is
accessing the
document remotely and loses his connection, he may lose his changes, be unable
to
continue, and may end up with a corrupted document.
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[0004] Another attempt to solve this problem has involved the use of
network
storage devices, whereby services offer users the opportunity to store their
documents
"in the cloud" ¨ that is, on servers accessible to users via the Internet or
other network.
In the above example, a user who is interested in working on a document from
multiple
locations can store the document on a network file server and then edit it
from home,
work, or any other location that provides network access to the file server.
SUMMARY
[0005] A file access server enables a user to obtain a URL or other
resource
identifier (generally, a "link") that can be shared with others, and which
provides access
to one or more files or file folders (generally, a "file set") managed by the
user and
stored on a network storage device operated by a file access service. The file
access
server generates the link and associates it with the file set specified by the
user as part of
the request. To generate the link, the file access server determines an
identifier for file
set that is to be referenced and creates a unique link mapped internally by
the file access
server to the referenced file set. In one embodiment, the link is opaque, such
that it is
impossible for a person not in possession of the link to determine the
associated files or
folders by inspection only, or to guess the link that provides access to a
given file set. In
other embodiments, the link contains a name of the files or folders in the
associated file
set.
[0006] In some embodiments, the links may be associated with other links,
thus
allowing multiple levels of indirection, and they may specify an application
or plug-in
used to view or otherwise interact with the associated file set.
[0007] The user may distribute the link to one or more recipients, who
access the
shared file set by following the link. The distribution of the link by the
user can be by e-
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mail, text, or social media service, such that the user can target a narrow or
a wide
audience.
[0008] The request from the user to create the link can be accomplished in
multiple
ways. For example, a user can use a web-based interface to the file access
service, or a
local client program coupled to the file access service, such as a file
browser on a
desktop computer or a file viewer on a handheld device, to create a link to
the selected
file set.
[0009] In one embodiment, the server itself facilitates distributing the
link, such as
by providing a mechanism for posting the link to a social networking service
or to a
microblogging service. Alternatively, the user distributes the link without
further use of
the server, such as by emailing the link to a mailing list, by posting the
link on a web
site, or the like.
[0010] In one embodiment, the server provides to the user a list of links
that he has
previously created. The user can revoke access to the shared files or other
content
simply by disabling or deleting the links.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a block diagram of an environment in which sharing can be
performed, according to one embodiment.
[0012] FIG. 2 is a block diagram illustrating the components of the file
access server
of FIG. 1, according to one embodiment.
[0013] FIGS. 3A-3C are user interface diagrams illustrating different user
interfaces
for specifying the creation of a link for file set sharing, according to
different
embodiments.
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[0014] FIG. 3D is a user interface diagram illustrating a representation of
a shared
file.
[0015] FIG. 3E is a user interface diagram illustrating a link management
user
interface.
[0016] FIG. 3F is a user interface diagram illustrating a representation of
a shared
folder.
[0017] FIG. 3G illustrates a user interface control that enables a user to
make a local copy
of a shared file.
[0018] FIG. 4 is a flowchart illustrating the actions involved in creating
a link to
files or other content and accessing that content via the link, according to
one
embodiment.
[0019] The figures depict various embodiments of the present invention for
purposes
of illustration only. One skilled in the art will readily recognize from the
following
description that other alternative embodiments of the structures and methods
illustrated
herein may be employed without departing from the principles of the invention
described herein.
DETAILED DESCRIPTION
[0010] FIG. 1 illustrates a file access server 100 in accordance with one
embodiment. File access server 100 includes a sharing module 105 and file
server 103.
Sharing module 105 provides functionality for sharable file links as described
below.
File server 103 provides network file storage for clients 110A and 110B of a
file access
service that includes file access server 100. For example, a first client 110A
may store
one or more files 111 on file server 103; a second client 110B may store one
or more
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files 112 on file server 103. In some embodiments, software executing on the
client 110
integrates the network-stored files with the client's local file system to
enable a user to
manipulate the network-stored files through the same user interface (UI) as is
used to
manipulate files on the local file system, e.g., via a file explorer. In FIG.
1, file sets 111
and 112 are illustrated within clients 110A and 110B with dotted lines to
illustrate this
integration; the files in the set are understood to reside on file server 103.
Note that in
some embodiments, clients 110 may additionally maintain a cache of the file
sets stored
on the network file server 103, to improve speed and reliability. Those of
skill in the art
will recognize that various methods exist to maintain synchronization between
local and
network based files. In other embodiments, clients 110 access file sets via a
web
interface, or through a custom-designed client installed on a client device.
Devices
might include, for example, a desktop or laptop computer, a tablet computing
device, or
a handheld computing device such as a personal digital assistant or a smart
phone (e.g.,
an IPHONE or BLACKBERRY, or a SYMBIAN or ANDROID-based smart phone).
One provider of a suitable file access service is Dropbox Inc., of San
Francisco,
California.
[0011] FIG. 1 illustrates only two clients, 110A and 110B, for purposes of
clarity.
When implemented, file access server 100 may be in communication with
thousands or
millions of clients, and each client may store one or multiple files on file
access server
100. When represented to the user, the files may be arranged in folders; and
folders
themselves may be arranged in other folders, as determined by the user;
however the
underlying storage architecture may be considerably different, and implemented
to
maximize storage efficiency, and without necessarily mirroring each user's
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hierarchy. File access server 100 and its components may be implemented using
any
appropriate hardware for performing file serving and storage¨solely for
clarity of
illustration and description, FIG. 1 illustrates only a single file access
server, and one
instance of relevant file stores and modules. Additionally, many components
required
for operation of a file access server and service, known to those of skill in
the art but not
germane to this description¨for example, network cards, CPUs, memory, and the
like¨are omitted for clarity.
[0012] FIG. 1 also illustrates a visitor 120, to whom a sharable link can
be provided.
As described further below, a visitor 120 need not have client software
installed, and
need not be a user of file access server 100, in order to access files via a
shared link.
[0013] Network 140 represents the communication pathways between the client
devices 110 and the file access server 100. In one embodiment, the network 140
uses
standard Internet communications technologies and/or protocols. Thus, the
network 140
can include links using technologies such as Ethernet, IEEE 802.11, IEEE
806.16,
WiMAX, 3GPP LTE, integrated services digital network (ISDN), asynchronous
transfer
mode (ATM), etc. Similarly, the networking protocols used on the network 140
can
include the transmission control protocol/Internet protocol (TCP/IP), the
hypertext
transport protocol (HTTP), the simple mail transfer protocol (SMTP), the file
transfer
protocol (FTP), etc. The data exchanged over the network 140 can be
represented using
technologies and/or formats including the hypertext markup language (HTML),
the
extensible markup language (XML), etc. In addition, all or some links can be
encrypted
using conventional encryption technologies such as the secure sockets layer
(SSL),
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Secure HTTP (HTTPS) and/or virtual private networks (VPNs). In another
embodiment, the entities can use custom and/or dedicated data communications
technologies instead of, or in addition to, the ones described above.
[0014] Clients 110 add files to file server 103 either through a manual
upload
process, or by synchronization with the local file system. In the embodiment
using
synchronization, each client 110 executes a synchronization client application
through
which files 111 of that client are specified for synchronization. The
synchronization
client application then provides the specified files to the file access server
100. The
specified files 111 are then provided to other ones of the clients 110, either
by "push" in
which the file access server 100 provides the files to the clients associated
with a user
who provided the files, or by "pull" in which the clients request the files
from the file
access server. The synchronization client applications and the file access
server 100
also ensure that changes to the synchronized files are likewise reflected
across all
associated clients 110.
[0015] In one embodiment, the synchronization client applications use local
peer-to-
peer synchronization for greater efficiency and do not require use of the file
access
server 100. For example, devices associated with the same user or having
access to the
same shared folder can determine whether they are on the same local area
network, and
if so establish a secure connection (e.g., via SSL) and effect synchronization
through
peer-to-peer transfer of files.
[0016] The synchronized files are typically provided only to clients 110
associated
with a user who provided the files. For example, if a particular user
registers his
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desktop, laptop, and handheld device with the file access server 100 as his
client devices
110, then the file access server and the synchronization applications on those
three
devices will synchronize the files with those devices and otherwise make the
file
available to the user via the user's login (e.g., via a web-based interface).
However, the
file access server 100 will not by default make the files available to devices
of other
users or via logins other than that of the user who provided the files.
[0017] Thus, the file access server 100 comprises a sharing module 105 that
provides links and enables file access by users other than those who initially
provided
the files. The sharing module 105 is described further below with respect to
FIG. 2.
[0018] FIG. 2 is a block diagram illustrating the components of the sharing
module
105 of FIG. 1, according to one embodiment. The sharing module 105 enables
access to
a user's specified file sets through the use of a shared link.
[0019] Sharing module 105 comprises a sharing database 220 specifying sets
of files
to be shared and the links used to share them. The sharing module 105 further
comprises a link generation module 230 for generating links and specifying
corresponding file sets to be shared, a link distribution module 240 for
facilitating
distribution of the links to other users, a link management module 250 for
viewing and
removing previously generated links, and a file access module 260 for
accessing the files
via the generated links.
[0020] The sharing database 220 specifies sets of files to be shared and a
mapping
between the shared files and the links used to reference them. For example,
the sharing
database might comprise a set of pairs, each pair mapping a particular file
set to a unique
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link (e.g., a URL) by which the file set can be accessed.
[0021] The link
generation module 230 generates a link corresponding to the file set
specified by the user requesting the sharing. The file set to which the link
corresponds
may include a single file or a set of files, or a container of files such as
one or more
folders, or even particular logical content such as a particular time sequence
of a video
file, particular slides of a presentation file, or particular records from a
database
constructed from multiple files.
[0022] The link
unambiguously identifies within sharing module 105 the file set to
which it corresponds. In one embodiment, upon receiving a request to share a
particular
file set via a link, the link generation module 230 generates a file set
descriptor
unambiguously describing the file set to be shared and a unique URL that
serves as the
link, and then saves an association of the file set descriptor and the URL in
the sharing
database 220. In one embodiment, the generated link is independent of the file
set
descriptor, such that the file set descriptor cannot be inferred from the
link, and vice
versa. This prevents malfeasance by making it essentially impossible to guess
a
sharable link if it is not already known. As an example, when sharing a folder
"JuneDocs" with a file ID of 3D8B99, the link generation module 230 might
generate
the unique (e.g., one way pad, or a pseudo-random value) URL
https://www.service.com/s/28rtiz608u2mnco/newdoc.pdf, where the URL component
28rtiz608u2mnco cannot be reverse-engineered, and accordingly create an entry
<3D8B99, https://www.service.com/s/28rtiz608u2mnco/newdoc.pdf> in the sharing
database 220. In one embodiment, the generated link can further be shortened.
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Referring to the prior example, the generated URL
https://www.service.com/s/28rtiz608u2mnco/newdoc.pdf can be shortened by a
link-
shortening service, located either on the file access service 100 or on some
remote third
party system, to the shorter URL http://db.tt/x0Founw, and an additional
association
between the generated link and the shortened link added to the sharing
database 220. In
another embodiment, the file set can be directly associated with a shortened
link, rather
than with an intermediate, longer generated link such as that described above.
In
various embodiments, the user can select a combination of a single file,
multiple files
within a folder, multiple folders, and multiple files across multiple folders
as the file set
to be associated with the single shared link.
[0023] In one embodiment, a user can generate multiple different links to
the same
file set. Thus, the user can more selectively control access to the file set
by distributing
different ones of the multiple different links to different sets of people,
revoking access
to the file set (if needed) via certain ones of the links while maintaining
access via the
other links. In another embodiment, an attempt to obtain a link to a file set
for which a
link has already been generated results in providing the same link that was
originally
generated.
[0024] In one embodiment, a user may specify a particular application or
plug-in
with which the file set should be viewed or otherwise interacted with. For
example, an
identifier that uniquely identifies an application or plug-in can be embedded
within the
generated link. As a more concrete example, the generated link for a given
file set could
be the URL https://www.service.com?app=lps3q/s/28rtiz608u2mnco/newdoc.pdf,
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which specifies (via the portion "app=lps3q") that some application uniquely
associated
with the identifier "ips3q" should be used to view the file set.
Alternatively, the
association between the link and the application or plug-in can be made in the
sharing
database 220 itself, rather than being embedded in the link. For example, a
user could
generate a first link to a file set that specifies use of a first application
for viewing the
file set, and a second link that specifies use of a second application, and
the sharing
database 220 would in turn then contain two corresponding entries: <file set
identifier,
first link identifier, first application identifier>, and <file set
identifier, second link
identifier, second application identifier>. In another embodiment, the sharing
module
105 itself selects the proper applications or plug-ins to use, e.g., based on
the types of
the files in the file set.
[0025] In one embodiment, links can be associated with other links so as to
create
a chain of links. For example, a first generated link associated with a file
set can in turn
be automatically associated with a shortened link, as discussed above.
Further, users
can explicitly specify multiple degrees of link associations. For example, a
user could
request generation of a first link to a given file set, and then request
generation of one or
more secondary links that are associated with the first link.
[0026] The user request that causes the link generation module 230 to
generate a
link can be specified in different manners in different embodiments. For
example, the
request can be made using the user interface provided by the client
synchronization
applications running on the clients 110, such as by designating a file within
a file
browser application and choosing a "Get shareable link" option 305 from a
resulting
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context-sensitive menu, as depicted in FIG. 3A, or by clicking a link icon 310
within a
file viewing application on a handheld device, as depicted in FIG. 3B. As
another
example, the request can be made from a web-based interface provided by the
file access
server 100, such as that depicted in FIG. 3C, in which the interface includes
a web-based
listing of files 316 stored on the file access server 100 and a "Get shareable
link" menu
item 316 associated with the various files.
[0027] In one embodiment, the sharing module 105 provides a web-based user
interface displaying the generated link, such as the interface depicted in
FIG. 3D.
Specifically, in FIG. 3D the text field 355 displays the link generated for
sharing an
image file, a representation of which is shown in viewing area 357. Further, a
sharing
options area 356 provides options for distributing the generated link, e.g.,
via social
networks.
[0028] The link distribution module 240 of FIG. 2 facilitates distribution
of the
links to users other than the users on behalf of whom the links were
generated. For
example, referring again to FIG. 3D, the options area 356 includes an option
356A for
distributing the generated link via a microblogging service, and another
option 356B for
distributing the generated link via a social networking service. Selection of
either option
prompts the user for the user's login information for the selected service.
Assuming that
correct login information is provided, the link distribution module 240 then
uses an API
of the selected service to disseminate the link via the service, such as
adding it as a post
to a user's page on the social networking service, or sending it as part of a
textual
message on the microblogging service. Those to whom to link is provided may in
turn
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provide the link to others, thereby further disseminating the sharing of the
associated file
set.
[0029] The link management module 250 permits a user to manage the links
that
he or she has previously generated. For example, a user selecting the "Linked
Items"
portion 371 of a user interface 370 of FIG. 3E causes the link management
module 250
to query the sharing database 220 for all the links that have been generated
for that user
and to display a list of the links in the list area 372. Each link has
associated "Get link"
and "Remove" actions 374, 375. The "Get link" action 374 displays the text of
the link
(e.g., URL) for dissemination by the user, as in text field 355 of FIG. 3D.
The
"Remove" action 375 revokes access to other users via that link, such as by
deleting the
entry for that link from the sharing database 220. Thus, no matter how large
the set of
users that have obtained the link¨and thus access to the corresponding file
set¨the
user that created the link can quickly and easily revoke the access simply by
removing
the link.
[0030] The file access module 260 provides the shared file set and/or
representations thereof to clients 110 in response to requests made via the
generated
link. For example, assume that a first user of the client 110A of FIG. 1
generated a
shortened link http://db.tt/x0Founw to a folder named "JuneDocs" with an ID of
3D8B99 and shared the link with a second user of the client 110B, such as by
sending
the link to an email account of the second user or posting the link to a
social networking
service accessible to the second user. When the second user clicks on or
otherwise
selects the link via the email or social networking service, a browser
application on the
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client 110B sends a corresponding request to the sharing module 105. For the
example
in which the link is the URL http://db.tt/x0Founw, the browser sends an HTTP
request
to the host db.tt, which is a domain name of the file access server 100,
including the
parameter x0Founw. . The request is handled by the file access module 260,
which
locates the entry in the sharing database 220 corresponding to the parameter
and extracts
the associated file set ID (namely, 3D8B99). Alternatively, if the folder is
associated
with a longer link https://www.service.com/s/28rtiz608u2mnco/newdoc.pdf, and
this
longer link is in turn associated with a shorter link http://db.tt/x0Founw,
then the file
access module first obtains the longer link from the shortened link using the
link
shortening service used to create the shortened link, and then determines the
file set
from the longer link and the sharing database 220. (If the link has been
removed, e.g.
via the "Remove" action 375 of FIG. 3E, the sharing database 220 will not
contain an
entry for that link. Thus, the file access module 260 will accordingly prevent
access to
the file set by informing the user requesting the access to the file set that
the file set is
not available.)
[0031] The file access module 260 then displays a representation of the
file set
corresponding to the file set ID. For example, referring again to FIG. 3D,
which
represents the sharing of a single image file, the viewing area 357 displays a
representation of the file¨namely, a thumbnail view. In one embodiment, the
entity
that receives and accesses the shared link may be a visitor 120, i.e., not a
registered user
of file access server 100.
[0032] In one embodiment, the file access module 260 displays the
representation
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of the file set using an application or plug-in corresponding to a unique
identifier
embedded within, or otherwise associated with, the generated link, as
discussed above.In
one embodiment, if the entity accessing the shared resources by shared link is
a
registered user of file access server 100, the user has an option of copying
the shared
files to her own file space on file server 103. FIG. 3G illustrates a user
interface control
356C that enables the user to make such a copy. Note that in one embodiment
the copy
is a static copy, such that if the original sharing user makes subsequent
changes to the
shared file, the changes are not reflected in the version of the file copied
by the user with
whom the link was shared.
[0033] FIG. 3F represents the sharing of a folder named "JuneDocs". The
text
field 355 again contains a URL link by which the folder is shared, and the
sharing
options area 356 provides options for distributing the link. Each distinct
type of file
within the folder is displayed within one of the separate groups 380, 385,
390. The type
may be determined in various ways, such as a file extension or other file
metadata, or the
content of the file itself. For example, group 380 includes the subfolders of
the
"JuneDocs" folder, group 385 includes the two image files that are within the
folder, and
group 390 includes a textual document 390A.
[0034] Each file (including folders) in the "JuneDocs" folder has an
associated
preview representation¨namely, previews 380A, 385A, 385B, and 390A. The form
of
the preview may be specific to the type of the associated file, such as an
image of a
folder and the associated folder name for folders 380, image thumbnails for
the images
385, and a document icon and an associated document name for the textual
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390. Selecting one of the preview representations causes the corresponding
file to be
displayed. For example, selecting a preview representation of a folder
displays the
contents of the folder, and selecting a preview representation of an image
obtains a copy
of the entire corresponding file, e.g., displaying the image at full size
within a browser
window or saving the original file to local file system on the client 110.
[0035] In one embodiment, in order to reduce storage requirements for the
file
access server 100, the document preview for a file is generated on demand the
first time
that the file is viewed, as opposed to being generated when the file is first
stored in the
file repository 210.
[0036] FIG. 4 is a flowchart illustrating the actions involved in creating
a link to
files or other content and accessing that content via the link, according to
one
embodiment.
[0037] The file access server 100 stores 410 a file within the file
repository 210.
As discussed above, the file could be manually uploaded by one of the clients
110, or it
could be stored as a result of file synchronization resulting from
coordination of the file
access server 100 and synchronization client applications installed on the
clients 110, for
example.
[0038] The sharing module 105 receives 420 an instruction from a user of a
client
110 to share a particular file set that includes the stored file, such as one
or more
individual files, one or more folders of files, or meaningful portions of
files or other
content. The request might be, for example, the result of one of the user
interface
actions depicted in FIGS. 3A-3C.
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[0039] Responsive to receiving the request, the sharing module 105
generates 430
a link specifying the file set, as discussed above with respect to the link
generation
module 230. The link may then be displayed to the user via a user interface
such as that
of FIGS. 3D or 3F. A user may manually distribute the link to others with whom
the
associated file is to be shared, or may use the optional link distribution
module 240 to
facilitate the distribution.
[0040] The sharing module 105 receives 440, from a second client (e.g.,
client
110B of FIG. 1) located remotely from the first client (e.g., client 110A)
that made the
request to share the file set, an access request via the link. The file access
module 260
then provides 450 a representation of the file set, as described above.
[0041] Reference in the specification to "one embodiment" or to "an
embodiment"
means that a particular feature, structure, or characteristic described in
connection with
the embodiments is included in at least one embodiment. The appearances of the
phrase
"in one embodiment" in various places in the specification are not necessarily
all
referring to the same embodiment.
[0042] It should be noted that the process steps and instructions can be
embodied
in software, firmware or hardware, and when embodied in software, can be
downloaded
to reside on and be operated from different platforms used by a variety of
operating
systems.
[0043] The operations herein may also be performed by an apparatus. This
apparatus may be specially constructed for the required purposes, or it may
comprise a
general-purpose computer selectively activated or reconfigured by a computer
program
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stored in the computer. Such a computer program may be stored in a computer
readable
storage medium, such as, but is not limited to, any type of disk including
floppy disks,
optical disks, CD-ROMs, magnetic-optical disks, read-only memories (ROMs),
random
access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards,
application
specific integrated circuits (ASICs), or any type of media suitable for
storing electronic
instructions, and each coupled to a computer system bus. Furthermore, the
computers
referred to in the specification may include a single processor or may be
architectures
employing multiple processor designs for increased computing capability.
[0044] The algorithms and displays presented herein are not inherently
related to
any particular computer or other apparatus. Various general-purpose systems
may also
be used with programs in accordance with the teachings herein, or it may prove
convenient to construct more specialized apparatus to perform the required
method
steps. The required structure for a variety of these systems will appear from
the
description below. In addition, the present invention is not described with
reference to
any particular programming language. It will be appreciated that a variety of
programming languages may be used to implement the teachings of the present
invention as described herein, and any references below to specific languages
are
provided for disclosure of enablement and best mode of the present invention.
[0045] While the invention has been particularly shown and described with
reference to a preferred embodiment and several alternate embodiments, it will
be
understood by persons skilled in the relevant art that various changes in form
and details
can be made therein without departing from the spirit and scope of the
invention.
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PCT/US2011/041531
[0046] Finally, it should be noted that the language used in the
specification has
been principally selected for readability and instructional purposes, and may
not have
been selected to delineate or circumscribe the inventive subject matter.
Accordingly, the
disclosure of the present invention is intended to be illustrative, but not
limiting, of the
scope of the invention, which is set forth in the following claims.
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