Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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SYSTEMS AND METHODS FOR PRESERVING AUDITABLE RECORDS OF
AN ELECTRONIC DEVICE
Technical Field
[0001] Embodiments described herein relate generally to the
communication of messages (e.g. SMS, MMS, Peer-to-Peer, IM, ICQ and PIN
messages) between users of mobile devices.
Background
[0002] For many messaging applications, it is beneficial to track and log
messages sent from one communication device to another. In the case of mobile
communication devices used to send SMS, MMS, Peer-to-Peer, IM, ICQ and
PIN, and other electronic messages, the log data records corresponding to
messages sent and received are typically stored locally on the device. Such
log
data records may be periodically uploaded to a centralized and networked log
database.
Brief Description of the Drawinas
[0003] For a better understanding of embodiments of the systems and
methods described herein, and to show more clearly how they may be carried
into effect, reference will be made, by way of example, to the accompanying
drawings in which:
[0004] FIG. 1 is a block diagram of a mobile device in one example
implementation;
[0005] FIG. 2 is a block diagram of a communication subsystem
component of the mobile device of FIG. 1;
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[0006] FIG. 3 is a block diagram of a node of a wireless network;
[0007] FIG. 4 is a block diagram illustrating components of a host system
in one example configuration; and
[0008] FIG. 5 is a flowchart illustrating a method of preserving auditable
records of an electronic device.
Detailed Description
[0009] The applicants have recognized that, in between the time an
electronic message is sent and when the message logs are uploaded to the
central log database, a user may delete the message logs (for instance in the
event an inappropriate message has been sent). This presents a potential
security loophole. Accordingly, in one broad aspect, there is provided a
method
for preserving data records of a system comprising a mobile electronic device
and a remote log storage configured to store data records corresponding to
auditable events. The mobile electronic device comprises memory storage
configured to store user data and the user data includes a data log comprising
data records corresponding to one or more auditable events. As well, the
mobile
electronic device is operatively coupleable to the remote log storage. The
method comprises receiving a command to delete the user data; identifying any
data records in the data log which have not been uploaded to the remote log
storage; storing any identified data records to the remote log storage; and
deleting the user data.
[0010] In some embodiments, the method may further comprise
operatively coupling the mobile electronic device to the remote log storage
prior
to storing the identified data records to the remote log storage. The
operative
coupling may comprise establishing a communication link between the electronic
device and the remote log storage. As well, the remote log storage may be
operatively coupled to a communications network.
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[0011] The mobile electronic device may comprise a communication
module configured to send and/or receive messages, and the one or more
auditable events may comprise the sending and/or receiving of a message. The
sent or received message may be selected from the group consisting of SMS,
MMS, Peer-to-Peer, IM, ICQ and PIN messages. The one or more auditable
events may also comprise a phone call or push-to-talk communication. The one
or more auditable events may also comprise uploading or downloading files. The
one or more auditable events may also comprise use of predetermined
applications.
[0012] A computer-readable medium may be provided which comprises
instructions executable on a processor of the computing device for
implementing
the method.
[0013] A mobile electronic device may also be provided on which an
application executes, wherein the application is programmed to perform the
method.
[0014] In yet another aspect a mobile electronic system is provided. The
system comprises a communication module; a memory configured to store user
data (wherein the user data includes a data log comprising data records
corresponding to one or more auditable events); a logging module operatively
coupled to the communication module, wherein the logging module is configured
to store data records in the data log corresponding to one or more auditable
events. The communication module is configured to store the data records to a
remote log storage. The system also comprises a deletion module configured to
delete user data stored in the memory. The deletion module is configured to
determine if any data records exist which have not been uploaded to the remote
log storage.
[0015] The communication module may be configured to establish a
communication link with the remote log storage. As well, the remote log
storage
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may be operatively coupled to a communications network. The communication
module may be configured to send and receive messages, and wherein the
auditable events comprise the sending or receiving of a message. Such sent or
received message may be selected from the group consisting of SMS, MMS,
Peer-to-Peer, IM, ICQ and PIN messages. The one or more auditable events
may also comprise a phone call or push-to-talk communication. The one or more
auditable events may also comprise uploading or downloading files. The one or
more auditable events may also comprise use of predetermined applications.
[0016] In yet a further aspect, a mobile electronic device may be provided
comprising a communication module; a memory storage configured to store a
data log; a logging module operatively coupled to the communication module,
wherein the logging module is configured to store, in the data log, data
records
corresponding to one or more auditable events. The communication module is
configured to output the data records. The device further comprises a deletion
module configured to delete data records stored in the data log, and the
deletion
module is configured to determine if any data records exist which have not
been
output.
[0017] The deletion module may be configured to determine if any data
records exist which have not been output, prior to deleting any such data
records. As well, the communication module may be configured to send and/or
receive messages, and the one or more auditable events may comprise the
sending and/or receiving of a message. The data records may comprise data
corresponding to the contents of, or a copy of, a message.
[0018] These and other aspects and features of various embodiments will
be described in greater detail below.
[0019] Embodiments described herein make reference to a mobile device.
A mobile device generally includes a two-way communication device with
advanced data communication capabilities having the capability to communicate
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with other computer systems. A mobile device may also include the capability
for
voice communications. Depending on the functionality provided by a mobile
device, it may be referred to as a data messaging device, a two-way pager, a
cellular telephone with data messaging capabilities, a wireless Internet
appliance,
or a data communication device (with or without telephony capabilities). A
mobile device communicates with other devices through a network of transceiver
stations.
[0020] To aid the reader in understanding the structure of a mobile device
and how it communicates with other devices, reference is made to FIGS. 1
through 3.
[0021] Referring first to FIG. 1, a block diagram of a mobile device in one
example implementation is shown generally as 100. Mobile device 100
comprises a number of components, the controlling component being
microprocessor 102. Microprocessor 102 controls the overall operation of
mobile
device 100. Communication functions, including data and voice communications,
are performed through communication subsystem 104. Communication module
or subsystem 104 receives messages from and sends messages to a wireless
network 200. In this example implementation of mobile device 100,
communication subsystem 104 is configured in accordance with the Global
System for Mobile Communication (GSM) and General Packet Radio Services
(GPRS) standards. The GSM/GPRS wireless network is used worldwide and it is
expected that these standards may be supplemented or eventually superseded
by newer standards such as Enhanced Data GSM Environment (EDGE) and
Universal Mobile Telecommunications Service (UMTS), High-Speed Packet
Access (HSPA), and Ultra Mobile Broadband (UMB), etc. New standards are still
being defined, but it is believed that they will have similarities to the
network
behaviour described herein, and it will also be understood by persons skilled
in
the art that the invention is intended to use any other suitable standards
that are
developed in the future. The wireless link connecting communication subsystem
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104 with network 200 represents one or more different Radio Frequency (RF)
channels, operating according to defined protocols specified for GSM/GPRS
communications. With newer network protocols, these channels are capable of
supporting both circuit switched voice communications and packet switched data
communications.
[0022] Although the wireless network associated with mobile device 100 is
a GSM/GPRS wireless network in one example implementation of mobile device
100, other wireless networks may also be associated with mobile device 100 in
variant implementations. Different types of wireless networks that may be
employed include, for example, data-centric wireless networks, voice-centric
wireless networks, and dual-mode networks that can support both voice and data
communications over the same physical base stations. Combined dual-mode
networks include, but are not limited to, Code Division Multiple Access (CDMA)
networks, CDMA2000 networks, Evolution Data Only (EV-DO) networks,
GSM/GPRS networks (as mentioned above), and third-generation (3G) and
beyond networks like EDGE, UMTS, and HSPA, etc. Some older examples of
data-centric networks include the MobitexTM Radio Network and the DataTACTM
Radio Network. Examples of older voice-centric data networks include Personal
Communication Systems (PCS) networks like GSM and Time Division Multiple
Access (TDMA) systems.
[0023] Microprocessor 102 also interacts with additional subsystems such
as a Random Access Memory (RAM) 106, and flash memory 108. The
microprocessor 102 may also be coupled to a display 110, auxiliary
input/output
(I/O) subsystem 112, serial port 114, keyboard 116, speaker 118, and
microphone 120 may also be provided. Similarly, short-range communications
subsystem 122 and other subsystems 124 may further be provided.
[0024] Some of the subsystems of mobile device 100 perform
communication-related functions, whereas other subsystems may provide
"resident" or on-device functions. By way of example, display 110 and keyboard
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116 may be used for both communication-related functions, such as entering a
text message for transmission over network 200, and device-resident functions
such as a calculator or task list. Operating system software used by
microprocessor 102 is typically stored in a persistent store such as flash
memory
108, which may alternatively be a read-only memory (ROM) or similar storage
element (not shown). Those skilled in the art will appreciate that the
operating
system, specific device applications, or parts thereof, may be temporarily
loaded
into a volatile store such as RAM 106.
[0025] Mobile device 100 may send and receive communication signals
over network 200 after required network registration or activation procedures
have been completed. Network access is associated with a subscriber or user of
a mobile device 100. To identify a subscriber, mobile device 100 may provide
for
a memory card 126, such as a Subscriber Identity Module or "SIM" card to be
inserted in a Memory card interface 128 in order to communicate with a
network.
memory card 126 is one type of a conventional "smart card" used to identify a
subscriber of mobile device 100 and to personalize the mobile device 100,
among other things. Without memory card 126, mobile device 100 may not be
fully operational for communication with network 200. Alternatively, by way of
example only, other types of "smart cards" which might be used may include an
R-UIM (removable user identity module) or a CSIM (CDMA (code division
multiple access) subscriber identity module) or a USIM (universal subscriber
identity module) card. By inserting memory card 126 into Memory card interface
128, a subscriber can access all subscribed services. Services may include
without limitation: web browsing and messaging such as e-mail, voice mail,
Short
Message Service (SMS), Multimedia Messaging Services (MMS), and Peer-to-
Peer messages such as PIN-to-PIN messages which may also be referred to
simply as PIN messages. As used in this context, a PIN (product identification
number) generally refers to a number that uniquely identifies the mobile
device
100, and a PIN message generally refers to a message addressed to one or
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more PIN numbers. More advanced services may include without limitation:
point of sale, field service and sales force automation. Memory card 126
includes a processor and memory for storing information. Once memory card
126 is inserted in memory card interface 128, it is coupled to microprocessor
102. In order to identify the subscriber, memory card 126 contains some user
parameters such as an International Mobile Subscriber Identity (IMSI). An
advantage of using memory card 126 is that a subscriber is not necessarily
bound by any single physical mobile device.
[0026] Memory card 126 may store additional subscriber information and
user data 125 for a mobile device as well, including datebook (or calendar)
information and a data log 127 of data records 127a corresponding to recent
message and call information. Such data records 127a may track auditable
events local to the device 100 (and which typically involve communications or
other messages which are routed through the corporate network, such as LAN
250). Such message types, for example, may include SMS (Short Messaging
Service), MMS (Multimedia Messaging Service), Peer-to-Peer, IM (Instant
Messaging), ICQ and PIN messages. In certain applications, the data records
127a may include copies of the messages sent or received. The auditable
events stored in the log 127 and data records 127a may also include data
corresponding to phone calls (eg. date and time of a call and third party
phone
number(s) participating in the phone call), "push-to-talk" communications and
GPS tracking data. The auditable events may also include data corresponding to
URLs, or other data relating to websites visited (and/or files uploaded or
downloaded), using certain predetermined applications (for example, online or
installed on the device 100) such as FACEBOOKt"' FLICKRtm or games. The
memory card 126 may include a logging module 127b operatively coupled to the
communication module 104 and programmed to store such data records 127a in
the data log 127. The user data 125 and data log 127 may reside in whole or in
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part on the memory card 126 or in other appropriate storage typically resident
on
the device 100.
[0027] Mobile device 100 may be a battery-powered device and may
include a battery interface 132 for receiving one or more rechargeable
batteries
130. Battery interface 132 may be coupled to a regulator (not shown), which
assists battery 130 in providing power V+ to mobile device 100. Although
current
technology makes use of a battery, future technologies such as micro fuel
cells
may provide the power to mobile device 100. In some embodiments, mobile
device may be solar-powered.
[0028] Microprocessor 102, in addition to its operating system functions,
enables execution of software applications on mobile device 100. A set of
applications that control basic device operations, including data and voice
communication applications, may be installed on mobile device 100 during its
manufacture. Another application that may be loaded onto mobile device 100 is
a personal information manager (PIM). A PIM has functionality to organize and
manage data items of interest to a subscriber, such as, but not limited to, e-
mail,
calendar events, voice mails, appointments, and task items. A PIM application
has the ability to send and receive data items via wireless network 200. PIM
data items may be seamlessly integrated, synchronized, and updated via
wireless network 200 with the mobile device subscriber's corresponding data
items stored and/or associated with a host computer system. This functionality
creates a mirrored host computer on mobile device 100 with respect to such
items. This can be particularly advantageous where the host computer system is
the mobile device subscriber's office computer system.
[0029] Additional applications may also be loaded onto mobile device 100
through network 200, auxiliary I/O subsystem 112, serial port 114, short-range
communications subsystem 122, or any other suitable subsystem 124. This
flexibility in application installation increases the functionality of mobile
device
100 and may provide enhanced on-device functions, communication-related
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functions, or both. For example, secure communication applications may enable
electronic commerce functions and other such financial transactions to be
performed using mobile device 100.
[0030] Serial port 114 enables a subscriber to set preferences through an
external device or software application and extends the capabilities of mobile
device 100 by providing for information or software downloads to mobile device
100 other than through a wireless communication network. The alternate
download path may, for example, be used to load an encryption key onto mobile
device 100 through a direct and thus reliable and trusted connection to
provide
secure device communication.
[0031] Short-range communications subsystem 122 provides for
communication between mobile device 100 and different systems or devices,
without the use of network 200. For example, subsystem 122 may include an
infrared device and associated circuits and components for short-range
communication. Examples of short range communication would include
standards developed by the Infrared Data Association (IrDA), Bluetooth, and
the
802.11 family of standards developed by IEEE.
[0032] In use, a received signal such as a text message, an e-mail
message, or web page download will be processed by communication
subsystem 104 and input to microprocessor 102. Microprocessor 102 will then
process the received signal for output to display 110 or alternatively to
auxiliary
I/O subsystem 112. A subscriber may also compose data items, such as e-mail
messages, for example, using keyboard 116 in conjunction with display 110 and
possibly auxiliary I/O subsystem 112. Auxiliary subsystem 112 may include
devices such as: a touch screen, mouse, track ball, infrared fingerprint
detector,
or a roller wheel with dynamic button pressing capability. Keyboard 116 may
comprise an alphanumeric keyboard and/or telephone-type keypad. Keyboard
116 may comprise a virtual keyboard or a physical keyboard or both. A
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composed item may be transmitted over network 200 through communication
subsystem 104.
[0033] For voice communications, the overall operation of mobile device
100 is substantially similar, except that the received signals may be
processed
and output to speaker 118, and signals for transmission may be generated by
microphone 120. Alternative voice or audio I/O subsystems, such as a voice
message recording subsystem, may also be implemented on mobile device 100.
Although voice or audio signal output is accomplished primarily through
speaker
118, display 110 may also be used to provide additional information such as
the
identity of a calling party, duration of a voice call, or other voice call
related
information.
[0034] Referring now to FIG. 2, a block diagram of the communication
subsystem component 104 of FIG. 1 is shown. Communication subsystem 104
comprises a receiver 150, and a transmitter 152. The subsystem 104 may also
be coupled to one or more embedded or internal antenna elements 154, 156,
and Local Oscillators (LOs) 158. A processing module such as a Digital Signal
Processor (DSP) 160, may also be provided.
[0035] The particular design of communication subsystem 104 is
dependent upon the network 200 in which mobile device 100 is intended to
operate, thus it should be understood that the design illustrated in FIG. 2
serves
only as one example. Signals received by antenna 154 through network 200 are
input to receiver 150, which may perform such common receiver functions as
signal amplification, frequency down conversion, filtering, channel selection,
and
analog-to-digital (A/D) conversion. A/D conversion of a received signal allows
more compiex communication functions such as demodulation and decoding to
be performed in DSP 160. In a similar manner, signals to be transmitted are
processed, including modulation and encoding, by DSP 160. These DSP-
processed signals are input to transmitter 152 for digital-to-analog (D/A)
conversion, frequency up conversion, filtering, amplification and transmission
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over network 200 via antenna 156. DSP 160 not only processes communication
signals, but also provides for receiver and transmitter control. For example,
the
gains applied to communication signals in receiver 150 and transmitter 152 may
be adaptively controlled through automatic gain control algorithms implemented
in DSP 160.
[0036] The wireless link between mobile device 100 and a network 200
may contain one or more different channels, typically different RF channels,
and
associated protocols used between mobile device 100 and network 200. A RF
channel is a limited resource that must be conserved, typically due to limits
in
overall bandwidth and limited battery power of mobile device 100.
[0037] When mobile device 100 is fully operational, transmitter 152 may
be keyed or turned on only when it is sending to network 200 and may otherwise
be turned off to conserve resources. Similarly, receiver 150 may be
periodically
turned off to conserve power until it is needed to receive signals or
information (if
at all) during designated time periods.
[0038] Referring now to FIG. 3, a block diagram of a node of an exemplary
wireless network is shown as 202. In practice, network 200 comprises one or
more nodes 202. Mobile device 100 communicates with a node 202 within
wireless network 200. In the example implementation of FIG. 3, node 202 is
configured in accordance with General Packet Radio Service (GPRS) and Global
Systems for Mobile (GSM) technologies; however, in other embodiments,
different standards may be implemented as discussed in more detail above.
Node 202 includes a base station controller (BSC) 204 with an associated tower
station 206, a Packet Control Unit (PCU) 208 added for GPRS support in GSM, a
Mobile Switching Center (MSC) 210, a Home Location Register (HLR) 212, a
Visitor Location Registry (VLR) 214, a Serving GPRS Support Node (SGSN) 216,
a Gateway GPRS Support Node (GGSN) 218, and a Dynamic Host Configuration
Protocol (DHCP) 220. This list of components is not meant to be an exhaustive
list of the components of every node 202 within a GSM/GPRS network, but rather
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serves as a list of components that are commonly used in communications
through network 200, for ease of illustration.
[0039] In a GSM network, MSC 210 is coupled to BSC 204 and to a
landline network, such as a Public Switched Telephone Network (PSTN) 222 to
satisfy circuit switched requirements. The connection through PCU 208, SGSN
216 and GGSN 218 to the public or private network (Internet) 224 (also
referred
to herein generally as a shared network infrastructure) represents the data
path
for GPRS capable mobile devices. In a GSM network extended with GPRS
capabilities, BSC 204 also contains a Packet Control Unit (PCU) 208 that
connects to SGSN 216 to control segmentation, radio channel allocation and to
satisfy packet switched requirements. To track mobile device location and
availability for both circuit switched and packet switched management, HLR 212
is shared between MSC 210 and SGSN 216. Access to VLR 214 is controlled by
MSC 210.
[0040] Station 206 comprises a fixed transceiver station. Station 206 and
BSC 204 together form the fixed transceiver equipment. The fixed transceiver
equipment provides wireless network coverage for a particular coverage area
commonly referred to as a"celP'. The fixed transceiver equipment transmits
communication signals to and receives communication signals from mobile
devices within its cell via station 206. The fixed transceiver equipment
normally
performs such functions as modulation and possibly encoding and/or encryption
of signals to be transmitted to the mobile device in accordance with
particular,
usually predetermined, communication protocols and parameters, under control
of its controller. The fixed transceiver equipment similarly demodulates and
possibly decodes and decrypts, if necessary, any communication signals
received from mobile device 100 within its cell. Communication protocols and
parameters may vary between different nodes. For example, one node may
employ a different modulation scheme and operate at different frequencies than
other nodes.
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[0041] For all mobile devices 100 registered with a specific network,
permanent configuration data such as a user profile is stored in HLR 212. HLR
212 also contains location information for each registered mobile device and
can
be queried to determine the current location of a mobile device. MSC 210 is
responsible for a group of location areas and stores the data of the mobile
devices currently in its area of responsibility in VLR 214. Further VLR 214
also
contains information on mobile devices that are visiting other networks. The
information in VLR 214 includes part of the permanent mobile device data
transmitted from HLR 212 to VLR 214 for faster access. By moving additional
information from a remote HLR 212 node to VLR 214, the amount of traffic
between these nodes can be reduced so that voice and data services can be
provided with faster response times and at the same time requiring less use of
computing resources.
[0042] SGSN 216 and GGSN 218 are elements added for GPRS support,
namely, packet switched data support, within GSM. SGSN 216 and MSC 210
have similar responsibilities within wireless network 200 by keeping track of
the
location of each mobile device 100. SGSN 216 also performs security functions
and access control for data traffic on network 200. GGSN 218 provides
internetworking connections with external packet switched networks and
connects to one or more SGSN's 216 via an Internet Protocol (IP) backbone
network operated within the network 200. During normal operations, a given
mobile device 100 performs a "GPRS Attach" to acquire an IP address and to
access data services. This normally is not present in circuit switched voice
channels as Integrated Services Digital Network (ISDN) addresses are used for
routing incoming and outgoing calls. Currently, all GPRS capable networks use
private, dynamically assigned IP addresses, thus requiring a DHCP server 220
connected to the GGSN 218. There are many mechanisms for dynamic IP
assignment, including using a combination of a Remote Authentication Dial-In
User Service (RADIUS) server and DHCP server. Once the GPRS Attach is
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complete, a logical connection is established from a mobile device 100,
through
PCU 208, and SGSN 216 to an Access Point Node (APN) within GGSN 218.
The APN represents a logical end of an IP tunnel that can either access direct
Internet compatible services or private network connections. The APN also
represents a security mechanism for network 200, insofar as each mobile device
100 must be assigned to one or more APNs and mobile devices 100 cannot
exchange data without first performing a GPRS Attach to an APN that it has
been
authorized to use. The APN may be considered to be similar to an Internet
domain name such as "myconnection.wireless.com".
[0043] Once the GPRS Attach is complete, a tunnel is created and all
traffic is exchanged within standard IP packets using any protocol that can be
supported in IP packets. This includes tunneling methods such as IP over IP as
in the case with some IPSecurity (IPsec) connections used with Virtual Private
Networks (VPN). These tunnels are also referred to as Packet Data Protocol
(PDP) Contexts and there are a limited number of these available in the
network
200. To maximize use of the PDP Contexts, network 200 will run an idle timer
for
each PDP Context to determine if there is a lack of activity. When a mobile
device 100 is not using its PDP Context, the PDP Context can be deallocated
and the IP address returned to the IP address pool managed by DHCP server
220.
[0044] Referring now to FIG. 4, a block diagram illustrating components of
a host system in one example configuration is shown. Host system 250 may
typically be, for example, a corporate office or other local area network
(LAN), or
may instead be a home office computer or some other private system, for
example, in variant implementations. As other examples, the host system 250
may comprise a LAN controlled by a governmental, healthcare, financial, or
educational institution. In this example shown in FIG. 4, host system 250 is
depicted as a LAN of an organization to which a user of mobile device 100
belongs.
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[0045] LAN 250 comprises a number of network components connected to
each other by LAN connections 260. For instance, a user's desktop computing
device ("desktop computer") 262a, which may be connected to an accompanying
cradle 264 for the user's mobile device 100, is situated on LAN 250. Cradle
264
for mobile device 100 may be coupled to computer 262a by a serial or a
Universal Serial Bus (USB) connection, for example. Other user computers 262b
are also situated on LAN 250, and each may or may not be equipped with an
accompanying cradle 264 for a mobile device. Cradle 264 facilitates the
loading
of information (e.g. PIM data, private symmetric encryption keys to facilitate
secure communications between mobile device 100 and LAN 250) from user
computer 262a to mobile device 100, and may be particularly useful for bulk
information updates often performed in initializing mobile device 100 for use.
The information downloaded to mobile device 100 may include S/MIME
certificates or PGP keys used in the exchange of messages. The process of
downloading information from a user's desktop computer 262a to the user's
mobile device 100 may also be referred to as synchronization.
[0046] It will be understood by persons skilled in the art that user
computers 262a, 262b will typically be also connected to other peripheral
devices
not explicitly shown in FIG. 4. Furthermore, only a subset of network
components of LAN 250 are shown in FIG. 4 for ease of exposition, and it will
be
understood by persons skilled in the art that LAN 250 will comprise additional
components not explicitly shown in FIG. 4, for this example configuration.
More
generally, LAN 250 may represent a smaller part of a larger network [not
shown]
of the organization, and may comprise different components and/or be arranged
in different topologies than that shown in the example of FIG. 4.
[0047] In this example, mobile device 100 communicates with LAN 250
through a node 202 of wireless network 200 and a shared network infrastructure
224 such as a service provider network or the public Internet. Access to LAN
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250 may be provided through one or more routers [not shown], and computing
devices of LAN 250 may operate from behind a firewall or proxy server 266.
[0048] In a variant implementation, LAN 250 comprises a wireless VPN
router [not shown] to facilitate data exchange between the LAN 250 and mobile
device 100. The concept of a wireless VPN router is new in the wireless
industry
and implies that a VPN connection can be established directly through a
specific
wireless network to mobile device 100. The possibility of using a wireless VPN
router has only recently been available and could be used when the new
Internet
Protocol (IP) Version 6 (IPV6) arrives into IP-based wireless networks. This
new
protocol will provide enough IP addresses to dedicate an IP address to every
mobile device, making it possible to push information to a mobile device at
any
time. An advantage of using a wireless VPN router is that it could be an off-
the-
shelf VPN component, not requiring a separate wireless gateway and separate
wireless infrastructure to be used. A VPN connection may include, for example,
a Transmission Control Protocol (TCP)/IP or User Datagram Protocol (UDP)/IP
connection to deliver the messages directly to mobile device 100 in this
variant
implementation.
[0049] Messages intended for a user of mobile device 100 are initially
received by a message server 268 of LAN 250. Such messages may originate
from any of a number of sources. For instance, a message may have been sent
by a sender from a computer 262b within LAN 250, from a different mobile
device
[not shown] connected to wireless network 200 or to a different wireless
network,
or from a different computing device or other device capable of sending
messages, via the shared network infrastructure 224, and possibly through an
application service provider (ASP) or Internet service provider (ISP), for
example.
[0050] Message server 268 typically acts as the primary interface for the
exchange of messages, particularly e-mail messages, within the organization
and
over the shared network infrastructure 224. Each user in the organization that
has been set up to send and receive messages is typically associated with a
user
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account managed by message server 268. One example of a message server
268 is a Microsoft ExchangeTM Server. In some implementations, LAN 250 may
comprise multiple message servers 268. Message server 268 may also be
adapted to provide additional functions beyond message management, including
the management of data associated with calendars and task lists, for example.
[0051] When messages are received by message server 268, they are
typically stored in a message store 269, from which messages can be
subsequently retrieved and delivered to users. For instance, an e-mail client
application operating on a user's computer 262a may request the e-mail
messages associated with that user's account stored on message server 268.
These messages may then typically be retrieved from message server 268 and
stored locally on computer 262a.
[0052] When operating mobile device 100, the user may wish to have e-
mail messages retrieved for delivery to the handheld. An e-mail client
application
operating on mobile device 100 may also request messages associated with the
user's account from message server 268. The e-mail client may be configured
(either by the user or by an administrator, possibly in accordance with an
organization's information technology (IT) policy) to make this request at the
direction of the user, at some pre-defined time interval, or upon the
occurrence of
some pre-defined event. In some implementations, mobile device 100 is
assigned its own e-mail address, and messages addressed specifically to mobile
device 100 are automatically redirected to mobile device 100 as they are
received by message server 268.
[0053] To facilitate the wireless communication of messages and
message-related data between mobile device 100 and components of LAN 250,
a number of wireless communications support components 270 may be provided.
In this example implementation, wireless communications support components
270 comprise a message management server 272, for example. Message
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management server 272 is used to specifically provide support for the
management of messages, such as e-mail messages, that are to be handled by
mobile devices. Generally, while messages are still stored on message server
268, message management server 272 can be used to control when, if, and how
messages should be sent to mobile device 100. Message management server
272 also facilitates the handling of messages composed on mobile device 100,
which are sent to message server 268 for subsequent delivery.
[0054] As will be understood, the message store 269 effectively operates
as a remote log storage (to which the mobile device 100 is operatively
coupleable) for storing data records 269a corresponding to the various
messages
(including for example SMS, MMS, and PIN messages) sent from and received
by the mobile device 100 (such message interaction included within the meaning
of "auditable events" as used herein). Referring briefly to FIG. 1, a
synchronization module 104a (which may, but does not necessarily, comprise
part of the communication subsystem 104 of the mobile device 100) is
programmed to periodically establish a wireless (often cellular) communication
link between the mobile device 100 and the LAN 250 to upload or otherwise
output the data records 127a from the data log 127 to the message log 269
which have not previously been uploaded, for completeness and to allow for
auditing of the message data records, as will be understood. This process may
include turning on the transmitter 152 and receiver 150 if they are shut down
at
the time to conserve power. The synchronization module 104a may flag or
otherwise store marking data indicating the data records 127a which have been
output or uploaded to the remote log 269.
[0055] The device 100 also includes a wipe application or deletion module,
referred to generally as 140, programmed to delete or erase some or all user
data 125 including the data log 127 and its data log records 127a. The wipe
application 140 is configured to check the data log 127 to determine if any
log
data records 127a exist which have not been uploaded to the remote log storage
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269. If any records 127a exist which have not been uploaded to the remote log
storage 269, then the wipe application 140 is programmed to initiate an upload
by the synchronization module 104a of any such data records 127a to the remote
log storage 269. Once the remote log storage 269 is fully updated, the wipe
application 140 is then free to delete any user data, including the data
records
127a in the data log 127. As will be understood, the wipe application 140 may
comprise a sub-module of another application, such as for example, the
operating system.
[0056] Referring back to FIG. 4, the message management server 272
may for example: monitor the user's "mailbox" (e.g. the message store
associated with the user's account on message server 268) for new e-mail
messages; apply user-definable filters to new messages to determine if and how
the messages will be relayed to the user's mobile device 100; compress and
encrypt new messages (e.g. using an encryption technique such as Data
Encryption Standard (DES) or Triple DES) and push them to mobile device 100
via the shared network infrastructure 224 and wireless network 200; and
receive
messages composed on mobile device 100 (e.g. encrypted using Triple DES),
decrypt and decompress the composed messages, re-format the composed
messages if desired so that they will appear to have originated from the
user's
computer 262a, and re-route the composed messages to message server 268 for
delivery.
[0057] Certain properties or restrictions associated with messages that are
to be sent from and/or received by mobile device 100 can be defined (e.g. by
an
administrator in accordance with IT policy) and enforced by message
management server 272. These may include whether mobile device 100 may
receive encrypted and/or signed messages, minimum encryption key sizes,
whether outgoing messages must be encrypted and/or signed, and whether
copies of all secure messages sent from mobile device 100 are to be sent to a
pre-defined copy address, for example.
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[0058] Message management server 272 may also be adapted to provide
other control functions, such as only pushing certain message information or
pre-
defined portions (e.g. "blocks") of a message stored on message server 268 to
mobile device 100. For example, when a message is initially retrieved by
mobile
device 100 from message server 268, message management server 272 is
adapted to push only the first part of a message to mobile device 100, with
the
part being of a pre-defined size (e.g. 2 KB). The user can then request more
of
the message, to be delivered in similar-sized blocks by message management
server 272 to mobile device 100, possibly up to a maximum pre-defined message
size.
[0059] Accordingly, message management server 272 facilitates better
control over the type of data and the amount of data that is communicated to
mobile device 100, and can help to minimize potential waste of bandwidth or
other resources.
[0060] It will be understood by persons skilled in the art that message
management server 272 need not be implemented on a separate physical server
in LAN 250 or other network. For example, some or all of the functions
associated with message management server 272 may be integrated with
message server 268, or some other server in LAN 250. Furthermore, LAN 250
may comprise multiple message management servers 272, particularly in variant
implementations where a large number of mobile devices is supported.
[0061] Certificates may be used in the processing of encoded messages,
such as e-mail messages, that are encrypted and/or signed, in accordance with
certain secure messaging protocols. While Simple Mail Transfer Protocol
(SMTP), RFC822 headers, and Multipurpose Internet Mail Extensions (MIME)
body parts may be used to define the format of a typical e-mail message not
requiring encoding, Secure/MIME (S/MIME), a version of the MIME protocol, may
be used in the communication of encoded messages (i.e. in secure messaging
applications). S/MIME enables end-to-end authentication and confidentiality,
and
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provides data integrity and privacy from the time an originator of a message
sends a message until it is decoded and read by the message recipient. Other
standards and protocols may be employed to facilitate secure message
communication, such as Pretty Good PrivacyTM (PGP) and variants of PGP such
as OpenPGP, for example. It will be understood that where reference is
generally made to "PGP" herein, the term is intended to encompass any of a
number of variant implementations based on the more general PGP scheme.
[0062] Secure messaging protocols such as S/MIME and PGP-based
protocols rely on pubiic and private encryption keys to provide
confidentiality and
integrity. Data encoded using a private key of a private key/public key pair
can
only be decoded using the corresponding public key of the pair, and data
encoded using a public key of a private key/public key pair can only be
decoded
using the corresponding private key of the pair. It is intended that private
key
information never be made public, whereas public key information is shared.
[0063] For example, if a sender wishes to send a message to a recipient in
encrypted form, the recipient's public key is used to encrypt a message, which
can then be decrypted only using the recipient's private key. Alternatively,
in
some encoding techniques, a one-time session key is generated and used to
encrypt the body of a message, typically with a symmetric encryption technique
(e.g. Triple DES). The session key is then encrypted using the recipient's
public
key (e.g. with a public key encryption algorithm such as RSA), which can then
be
decrypted only using the recipient's private key. The decrypted session key
can
then be used to decrypt the message body. The message header may be used
to specify the particular encryption scheme that must be used to decrypt the
message. Other encryption techniques based on public key cryptography may
be used in variant implementations. However, in each of these cases, only the
recipient's private key may be used to facilitate successful decryption of the
message, and in this way, the confidentiality of messages can be maintained.
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[0064] As a further example, a sender may sign a message using a digital
signature. A digital signature generally comprises a digest of the message
(e.g.
a hash of the message) encoded using the sender's private key, which can then
be appended to the outgoing message. To verify the digital signature of the
message when received, the recipient uses the same technique as the sender
(e.g. using the same standard hash algorithm) to obtain a digest of the
received
message. The recipient also uses the sender's public key to decode the digital
signature, in order to obtain what should be a matching digest for the
received
message. If the digests of the received message do not match, this suggests
that either the message content was changed during transport and/or the
message did not originate from the sender whose public key was used for
verification. Digital signature algorithms are designed in such a way that
only
someone with knowledge of the sender's private key should be able to encode a
signature that the recipient will decode correctly using the sender's public
key.
Therefore, by verifying a digital signature in this way, authentication of the
sender
and message integrity can be maintained.
[0065] An encoded message may be encrypted, signed, or both encrypted
and signed. In S/MIME, the authenticity of public keys used in these
operations
is validated using certificates. A certificate is a digital document issued by
a
certificate authority (CA). Certificates are used to authenticate the
association
between users and their public keys, and essentially, provides a level of
trust in
the authenticity of the users' public keys. Certificates contain information
about
the certificate holder, with certificate contents typically formatted in
accordance
with an accepted standard (e.g. X.509). The certificates are typically
digitally
signed by the certificate authority.
[0066] In PGP-based systems, a PGP key is used, which is like an
S/MIME certificate in that it contains public information including a public
key and
information on the key holder or owner. Unlike S/MIME certificates, however,
PGP keys are not generally issued by a certificate authority, and the level of
trust
CA 02638443 2008-07-31
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in the authenticity of a PGP key typically requires verifying that a trusted
individual has vouched for the authenticity of a given PGP key.
[0067] For the purposes of the specification and in the claims, the term
"certificate" is used generally to describe a construct used to provide public
keys
for encoding and decoding messages and possibly information on the key holder,
and may be deemed to include what is generally known as a "PGP key" and
other similar constructs.
[0068] Standard e-mail security protocols typically facilitate secure
message transmission between non-mobile computing devices (e.g. computers
262a, 262b of FIG. 4; remote desktop devices). In order that signed messages
received from senders may be read from mobile device 100 and that encrypted
messages be sent from mobile device 100, mobile device 100 is adapted to store
public keys (e.g. in S/MIME certificates, PGP keys) of other individuals. Keys
stored on a user's computer 262a will typically be downloaded from computer
262a to mobile device 100 through cradle 264, for example.
[0069] Mobile device 100 may also be adapted to store the private key of
the public key/private key pair associated with the user, so that the user of
mobile
device 100 can sign outgoing messages composed on mobile device 100, and
decrypt messages sent to the user encrypted with the user's public key. The
private key may be downloaded to mobile device 100 from the user's computer
262a through cradle 264, for example. The private key is preferably exchanged
between the computer 262a and mobile device 100 so that the user may share
one identity and one method for accessing messages.
[0070] User computers 262a, 262b can obtain S/MIME certificates and
PGP keys from a number of sources, for storage on computers 262a, 262b
and/or mobile devices (e.g. mobile device 100). These certificate sources may
be private (e.g. dedicated for use within an organization) or public, may
reside
locally or remotely, and may be accessible from within an organization's
private
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network or through the Internet, for example. In the example shown in FIG. 4,
multiple public key infrastructure (PKI) servers 280 associated with the
organization reside on LAN 250. PKI servers 280 include a CA server 282 that
may be used for issuing S/MIME certificates, a Lightweight Directory Access
Protocol (LDAP) server 284 that may be used to search for and download
S/MIME certificates and/or PGP keys (e.g. for individuals within the
organization),
and an Online Certificate Status Protocol (OCSP) server 286 that may be used
to
verify the revocation status of S/MIME certificates, for example.
[0071] Certificates and/or PGP keys may be retrieved from LDAP server
284 by a user computer 262a, for example, to be downloaded to mobile device
100 via cradle 264. However, in a variant implementation, LDAP server 284 may
be accessed directly (i.e. "over the air" in this context) by mobile device
100, and
mobile device 100 may search for and retrieve individual certificates and PGP
keys through a mobile data server 288. Similarly, mobile data server 288 may
be
adapted to allow mobile device 100 to directly query OCSP server 286 to verify
the revocation status of S/MIME certificates.
[0072] In variant implementations, only selected PKI servers 280 may be
made accessible to mobile devices (e.g. allowing certificates to be downloaded
only from a user's computer 262a, 262b, while allowing the revocation status
of
certificates to be checked from mobile device 100).
[0073] In variant implementations, certain PKI servers 280 may be made
accessible only to mobile devices registered to particular users, as specified
by
an IT administrator, possibly in accordance with an IT policy, for example.
[0074] Other sources of S/MIME certificates and PGP keys [not shown]
may include a Windows certificate or key store, another secure certificate or
key
store on or outside LAN 250, and smart cards, for example.
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[0075] Further features of the above-mentioned example embodiments
and features of other example embodiments will be apparent from the
description
that follows with reference to FIG. 5.
[0076] Referring now to FIG. 5, a flowchart illustrating a method for
preserving data records of a system comprising a mobile electronic device and
a
remote log storage, is shown generally as 300. Additional details of some of
the
features described below in respect of the method 300 may be described earlier
in the present specification.
[0077] In at least one embodiment, the method 300 is performed by the
wipe application 140. The method is commenced by , by the wipe application
140 receiving a command, to erase user data stored on the electronic device
100
(Block 302).
[0078] Upon receipt of the erase command, the wipe application 140
determines if any data records 127a in the data log 127 exist which do not
correspond to data records 269a in the remote log storage 269 (Block 304). If
all
data records 127a have been uploaded to the remote log storage 269, the wipe
application 140 is programmed to proceed with deleting the user data stored on
the device 100, including the data records 127a (Block 306).
[0079] However, if any data records 269a exist which have not been
uploaded to the remote log storage 269, the previously non-uploaded data
records 127a are uploaded to the remote log storage 269 (Block 308). To do so,
the wipe application 140 causes the synchronization module 104a to upload any
such data records 127a to the remote log storage 269. As noted previously, the
synchronization module may establish a communication link between the mobile
device and the LAN 250 (e.g. via a wireless link, such as via a cellular,
BLUETOOTH or Wi-Fi link, or via a wireline link, such as via a USB cable,
etc.) to upload data records 127a from the data log 127 to the message log
records 269 which have not previously been uploaded, for completeness and to
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allow for auditing of the message data records, as will be understood. This
process may include turning on the transmitter 152 and receiver 150 if they
are
shut down at the time to conserve power.
[0080] Once all of the data records 127a have been uploaded to the
remote log storage 269, the wipe application 140 is programmed to proceed with
deleting the user data stored on the device 100, including the data records
127a
(Block 310).
[0081] It should be understood that the methods described herein may be
provided as executable software instructions stored on computer-readable
media, which may include transmission-type media.
[0082] The invention has been described with regard to a number of
embodiments. However, it will be understood by persons skilled in the art that
other variants and modifications may be made without departing from the scope
of the invention as defined in the claims appended hereto.
