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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
REFERENCE TO A MICROFICHE APPENDIX
Not Applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains generally to communication systems, and more
particularly to a communication system, which utilizes an intelligent
location agent to provide, on demand, the current locations of one or more
remote location devices as well as sets of past locations of the devices.
2. Related Art
In many fields of human endeavor it is useful to know the precise
geographic location of a person or object. For example, if an individual
were mentally handicapped, it would be desirable to continuously know the
individual's exact whereabouts in order to ensure his or her well-being.
Similarly, it would be useful to know in real time the location of a
delivery person in the field so that more efficient delivery scheduling
may be accomplished. A multitude of other applications for geographic
location information can be found in the commercial sector, civilian
agencies, law enforcement agencies, and the military., With the arrival of
the Global Positioning System (GPS), which provides three-dimensional
coordinates of any location on earth, such remote locator systems have
become a practicality.
What is needed is a system (hardware, software, protocols) that provides,
on demand, the current locations of one or more remote location devices as
well as sets of past locations of the devices. The past locations should
be selected according to intelligent algorithms so as to deliver only
useful information and to minimize memory requirements. The system should
also be able to initiate alerts based upon the current location of the
devices and the intelligent location algorithms.
BRIEF SUMMARY OF THE INVENTION
In one aspect of the present invention there is provided a remote location
system for communicating location information between a movable remote
location device that generates such location information and a location
service comprising at least one remote location device having detecting
means for determining a location of the remote location device,
communication means for communicating the location information to the
service and from the service to a user of the service, and intelligent
location agent means for selectively defining the location information in
terms of location event data to be communicated to the locator service.
The communication means includes a communication protocol for
communicating with a remote location device and includes a computer system
for communicating with a remote locator device by way of the protocol. The
communication means also includes user communication modes for
communication between a user and the service. The modes include
service-initiated communication from the service to a user. The
communication means further includes protocols for controlling
communication between the service and a user. The communication means
includes software for integrating communication between the service and a
remote locator device and between a user and the service.
The intelligent location agent means defines location event data to include
a remote locator device crossing a specified boundary as established by
the location service. The intelligent location agent means can also define
location event data to include a remote location device traveling a
specified minimum distance from a prior location as established by the
location service and to define location event data to include a remote
locator device exceeding a specified velocity as established by the
location service.
In other aspects of the present invention there is provided a remote
location system for communicating location information between a movable
remote location device that generates such location information and a
location service comprising a plurality of remote location devices each
having detecting means for determining the location of the remote location
device, communication means for communicating the location information to
the location service from each remote location device and from the
location service to a user of the location service, and program means for
selectively defining the location information in terms of location event
data to be communicated to the location service and under what
circumstances the data is communicated from the service to a user of the
service. The communication means includes a communication protocol for
communicating with each remote location device and a computer system for
communicating with each remote locator device by way of the protocol. The
communication means also includes user communication modes for
communication between a user and the location service and
service-initiated communications from the location service to a user. The
communication means includes software protocols for controlling
communication between the location service and a user and includes human
operator protocols for controlling communication between the location
service and a user.
The program means defines location event data to include a remote locator
device crossing a specified boundary as established by the location
service; a remote location device traveling a specified minimum distance
from a prior location as established by the location service; and a remote
locator device exceeding a specified velocity as established by the
location service.
Another aspect of the present invention provides a remote location system
for communicating location information between a movable remote location
device that generates such location information and a location service
comprising at least one remote location device having detecting means for
determining a location of a remote location device identified by the
system and memory for storing the location information, communication
means for communicating the location information to the location service
and from the service to a user of the location service, and intelligent
location agent means for selectively defining the location information in
terms of location event data to be communicated to the locator service.
The intelligent location agent means includes at least one location
algorithm for selecting which location data is to be stored in the memory
of the remote locator device. The location algorithm is for minimum
distance sampling whereby the current location is recorded only when the
distance from the most recently recorded location to the current location
is at least as much as some prescribed distance; for fixed time interval
sampling whereby the current location is recorded only when a prescribed
amount of time has passed since the most recently recorded location; and
for velocity-determined sampling whereby the rate that the locations are
recorded depends on the velocity of a remote location device.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The novel features which are believed to be characteristic of this
invention are set forth with particularity in the appended claims. The
invention itself, however, both as to its organization and method of
operation, together with further objects and advantages thereof, may best
be understood by reference to the following description, taken in
connection with the accompanying drawings, in which:
The sole figure is a block diagram of the system in accord with the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
A remote location system consists of one or more remote location devices, a
protocol for communicating with the remote location devices, and a service
(protocol, software, and hardware) for delivering location information
(from the location devices) on demand.
A remote location device is an electronic assembly that has a means for
establishing its location and an ability to communicate that location to a
querying agent at another location.
Purpose
This invention is a system that provides, on demand, the current locations
of one or more remote location devices as well as sets of past locations
of the devices. The sets of past locations may be selected according to an
intelligent algorithm so as to avoid inundating the user with trivial data
and so as to minimize memory requirements. The system 10 may initiate
alerts based upon the current location of the device 11 and the
intelligent location capability.
Parts--The intelligent location system 10 has four parts as shown in the
figure.
1. The remote location devices 11,
2. The protocol for communicating with the remote location devices
(communication protocol) 12,
3. The delivery service 13, and
4. The intelligent location agent 18.
Descriptions and examples of remote location devices 11 may be found in
Appendix 2.
A description of the protocol for communication with remote location
devices 12 is in Appendix 3.
The delivery service 13 consists of:
a) A computer system 14, which is capable of communicating with the remote
location devices 11 through the communication protocol 12. The computer
system 14 may be distributed across multiple physical locations or may be
in a single site. In this context, "computer system" includes hardware
(including, but not limited to, CPU, peripheral devices such as modems,
network interface cards, data storage devices, and a console and other
input and output devices) and operating software (including, but not
limited to, an operating system and device controllers).
b) One or more client communication modes 15. Example client (or end user)
communication modes 15 include (but are not limited to):
i. Internet access (including world wide websites),
ii. telephone call centers (including automated voice response systems,
human operators, and combinations of the two),
iii. local and wide area networks, and
iv. direct console access.
The computer system 14 is preferably capable of initiating communication
with clients 20. System-initiated communication modes include (but are not
limited to):
i. email messages,
ii. fax messages,
iii. automated voice phone calls,
iv. messages to human operators' monitors directing the operators to make
telephone calls.
c) Software and human operator protocols 16 for controlling communication
with clients. Functions that may be required of client communication
software 16 include (but are not limited to):
i. identify clients (verify account numbers and passwords),
ii. verify account status,
iii. manage accounts,
iv. accept and handle location requests,
v. accept and handle changes to smart location parameters,
vi. accept and handle requests for historical location data,
vii. initialize remote location devices 11,
viii. deliver locations to clients (maps, directions, or addresses faxed,
e-mailed, or described by operator), and
ix. refine location data (scrolling, zooming, labeling of maps, conversion
of measurement units).
Features that may be required of operator protocols 16 include (but are not
limited to):
i. specification of information to be acquired from client 20 and order of
acquisition,
ii. specification of which operators are allowed access to which data (As
examples, the location operators may not be allowed access to identity
data, and the account management operators may not be allowed access to
current or historical location data).
d) Software for integrating 17 client communication, communication with the
remote location devices; and access to necessary data (including, but not
limited to data related to states of devices 11, smart location
algorithms, and client accounts).
The intelligent location agent 18 is software that allows the location
service 19 to be configured with user-specified location events of
interest and which determines the location service's responses to the
location events.
Examples of location events include (but are not limited to):
Crossing a specified boundary:
1. An amusement park rents remote location devices 11 to customers and
wants to know when a device 11 travels more than 10 yards outside of the
gates of the park.
2. A pharmaceutical company keeps track of the time the sales force is
within physicians' offices (versus traveling between offices) by setting
multiple boundaries, one around each physician's office.
3. An alarm installation contractor's employees drive company vans to many
small jobs. By setting a boundary around each job site, the contractor is
able to precisely monitor time spent on each job.
Traveling a specified minimum distance since the last recorded location
event:
4. A person's movements are monitored over the course of a day or a week.
It is common for a person to spend lengthy periods in a small location (at
home, at the office, at a restaurant, in a grocery store). Only movements
from one location to another need to be recorded; continually recording
that the person is in the office every two minutes for four hours would
waste memory; transmitting the information would waste battery charge. So,
a new location and time are recorded only if the location is at least 25
yards away from the most recently recorded location.
Exceeding a specified velocity:
5. A delivery service monitors the speed of each of its vehicles (using
elapsed time and distance traveled between locations observed at short
time intervals) to ensure that drivers do not exceed legal speed limits.
Examples of responses to location events include (but are not limited to):
1. Send an alert to the client 20 (potentially appropriate for location
event examples 1 and 5).
2. Record the event for later download to the client 20 (potentially
appropriate for location event examples 2, 3, and 4).
Novel Features--The present invention is the first remote location system
to include an intelligent location agent. The intelligent agent allows the
system to conserve memory and/or power resources on board the remote
locator devices by selectively recording location data. It also allows the
system to send alert messages when location events of interest occur, and
allows the system's delivery service to present information to the clients
in the most useable format (digesting large quantities of location data
and presenting useful extracts). Additional features are discussed below.
1. First Embodiment--Personal Locator System
This embodiment is the first remote location system:
To include comprehensive location data (personal, vehicle, goods, etc.)
with an intelligent agent.
To-provide multiple client access modes with an intelligent agent.
To provide minimum-distance sampling for recording location events.
To provide velocity-determined sampling for recording events.
2. Second Embodiment--Park Location System
This embodiment is the first park locator system:
To include an intelligent agent 18.
To notify the system owner if a remote location device 11 leaves the park.
To provide location information without the use of permanently installed
transmitters.
3. Third Embodiment--Sales Force Location System
This embodiment is the first sales force location system.
To provide real-time data.
To include an intelligent agent 18.
To provide verification that a sales representative has visited a specific
client.
To provide differentiation between various internal locations of a client's
office.
To provide data on how many clients and of what type are visited on a given
day.
To provide data on how much time is spent at each location and in transit.
4. Fourth Embodiment--Delivery Fleet Location System
To provide an intelligent location agent 18.
That can be utilized by a fleet of bicycles.
That can be carried by delivery personnel to provide data on personnel
within buildings and at other locations.
SYSTEM DESCRIPTION
Embodiments of the intelligent remote location system 10 include (but are
not limited to) the following examples.
Personal Location System
The purpose of this embodiment of the invention is to provide an ability to
locate an individual person without the person having to actively
participate in the act of location, or to locate valuable goods. The
embodiment also provides an ability to track the movements of the person,
and provides the person with the ability to send an alarm signal in an
emergency.
The remote location devices 11 are small and unobtrusive and may be built
with flexible circuitry (Appendix 2). This allows the devices to be
conveniently carried on a person or valued pet. Methods of carrying a
remote location device 11 include, but are not limited to, the following:
1. The device 11 may be sewn into clothing;
2. The device 11 may be embedded in a watch or watchband or a pet collar;
3. The device 11 may be carried in a wallet or a purse.
The remote location devices 11 may also be inserted into or attached to
shipments of valuable goods or attached to a vehicle. Because the device
11 is small and unobtrusive, it should be unnoticed in the event of theft
or abduction, allowing the client 20 to locate and recover the person,
pet, goods or vehicle. Because the flexible version of the remote location
device 11 can be sewn into clothing (or a pet collar), the device will not
annoy non-responsible carriers (including, but not limited to, persons
with Alzheimer's disease, autistic or very young children, and pets). Thus
it is unlikely that a non-responsible carrier will discard the device 11.
The remote location devices 11 use global positioning system (GPS)
satellite receivers to determine location and AMPS cellular telephones to
communicate with the location system 19. Consequently, the remote location
device 11 can determine can determine its position virtually anywhere in
the world, and can communicate from any location that has AMPS cellular
coverage (including most of North America).
The remote location devices 11 have on-board memory and logic allowing
storage of a history of 200 or more locations and times. Part of the
intelligent location agent 18 resides in the remote location devices
11--that part which determines whether the device has moved a set distance
since the last recorded location. If so, the device 11 will store the
current location in memory along with the most recent 199 locations. If
the device 11 has not moved far enough to satisfy the algorithm, the
current location will be discarded. When the client 20 requests the
location of the device 11, the past history will also be available.
Another part of the intelligent location agent 18 resides in the service
19: The client 20 specifies named locations by specifying the centers,
radii and names of the locations. (Named locations might include such
locations as "home", "school", "mall", "Grandmother's house", etc.) If the
remote location device 11 is in one of the named locations when the
service 19 delivers the location information, the service 19 will deliver
that name as the location.
Clients 20 may access the service 19 through three modes:
1. Automated voice response system,
2. Call center staffed by human operators,
3. World-wide-website.
In each mode, the client 20 first is identified (through account number and
password) and then may request: the current location of the remote
location device 11 or may request the location history of the device 11
(up to 200 most recently recorded locations and times). The service 19
telephones the remote location device 11 to acquire the requested
information and then delivers the information to the client 20. The
information may be delivered as named location(s), as a map (via
world-wide-web, e-mail or fax), or by a human operator describing a map
delivered to the operator's computer display. Through the same access
modes, the client 20 may set parameters controlling the intelligent agent
18 (whether to record at specified fixed time intervals or when movement
exceeds a specified distance, named location information, etc.).
The remote location device 11 may initiate communication with the remote
location service in two circumstances. If the battery is low, the device
11 will call a dedicated phone number to report this fact and download its
history of locations before going into a dormant mode. If the panic button
on the device 11 is pressed, the device 11 will call a dedicated emergency
phone number and the system 19 will initiate a specified emergency
procedure (typically a call to 911 in the appropriate jurisdiction and
notification of the client 20 that an emergency is in progress).
Remote Location Device 11 (Appendix 2) The components of this embodiment
are as follows:
The remote location device 11 is a self-contained unit combining:
1. a battery,
2. global positioning (GPS) antenna and circuitry,
3. cellular telephone antenna and circuitry (AMPS),
4. modem circuitry,
5. on-board memory for storing data for 100 locations (including latitude,
longitude, elevation, time, and number of satellites contributing to the
location fix),
6. logical processing capability (a CPU).
The remote location device 11 also has a panic button 21 that the carrier
may press in an emergency. If the panic button 21 is pressed, the device
11 calls a specified telephone number to inform the location service 19
that an emergency is occurring. The service 19 then alerts the appropriate
agency (PSAP and/or the client 20 ) and requests the device's current
location at short intervals until the emergency is over.
The remote location device 11 fixes its location at regular intervals
(typically at least once per minute). A sample of these location fixes is
saved. The sample is chosen according to an intelligent location
algorithm.
To conserve battery power the device 11 checks in with the cellular
telephone network less frequently. A typical setting for cellular
telephone contact is for the device 11 to advise the network of its
presence once every three minutes and to be available to receive calls for
60 seconds after each notification of availability.
If the device's battery level falls below a prescribed level, the device 11
calls a specified primary phone number to inform the service 19 that the
battery is low and to download the stored location data. Then the device
11 becomes dormant until the battery is recharged.
Through the location service 19, a client 20 can:
1. request the current location of his device 11,
2. request the stored past locations,
3. instruct the device 11 to store locations either
a. at fixed time intervals (intervals specified by the user),
b. as the device 11 moves a fixed distance (distance specified by the user)
from the most recently stored location, or
c. according to other intelligent location algorithms.
When any of these actions is initiated, the service 19 telephones the
remote location device 11 through the service's modem and the device's
cell phone), issues the instruction or requests the data, receives
confirmation and/or data from the device, and then delivers the data to
the client 20 in suitable format.
Before a personal location device 11 can be put into service, it must be
initialized or registered with the location service 19. This is done via
the device's cell phone in a call initiated by the device 11. One
mechanism, but not the only mechanism for doing this is for the device 11
to store a logical flag indicating whether it has been initialized. If it
has not been initialized, then pressing the panic button will cause the
device 11 to place an initialization call to the location service 19.
The device 11 is provided (by its manufacturer) with an electronic serial
number (ESN) that is unique to that specific device. The device 11 also
knows:
1. whether it has been assigned a mobile identification number (MIN--its
cell phone number) and a cellular home system identification number (SID)
by a cellular phone service provider,
2. its MIN and SID if they have been assigned,
3. its manufacturer's identification code,
4. its manufacturer's private encryption key (for a public key encryption
algorithm),
5. its manufacturer's public encryption algorithm,
6. the service's public encryption (for the public key encryption
algorithm),
7. a symmetric key encryption algorithm, the algorithm's identification
code, and the device's unique encryption key,
8. the error-detecting algorithm used by the service,
9. the initialization phone number for the service.
Items 1, 2, 3, and 8, the identification code from Item 7, and the ESN are
transmitted to the location service during initialization.
The service 19 knows:
1. the public key and encryption algorithm associated with every
manufacturer's identification code,
2. The symmetric encryption algorithm associated with every symmetric
encryption identification code,
3. primary and secondary phone numbers for the device 11 to call,
4. appropriate, available MIN and SID for the device 11 if these have not
already been assigned.
Items 3 and 4 are transmitted to the remote location device 11 during
initialization.
Communication Protocol 12 (Appendix 3) Part 1--Initialization The physical
communication channel layer is the cellular telephone network and the
telephone network between the cellular telephone service provider and the
location service's physical location.
The link layer is an onboard modem using a standard low-level modulation
protocol such as V.34, V.32bis, V.32, V.22bis, or V.22.
For the initial phase of the initialization call, the encryption/encoding
layer will be encryption-null (no encryption, error-detection encoding
with the algorithm used by the service). As communication is established
and an encryption algorithm is negotiated, the encryption/encoding layer
will convert (in stages, as described in the following description of an
initialization call) to the agreed upon encryption algorithm. An error in
the initialization call will require re-transmission of the block
containing the error. After five unsuccessful attempts to transmit a block
error-free, the initialization call will be terminated by the service 19.
The content layer consists of the legal instructions and data identified in
the following description of an initialization call.
Description of an initialization call Once modem handshaking has been
completed, the device 11 will send a four-character device manufacturer
identification code (unencrypted). (The four-character length is before
encoding for error detection). The manufacturer and the owner of the
service 19 will agree upon each manufacturer's identification code in
advance. An unrecognized code is an error.
Next the device 11 will send a code identifying a symmetric encryption
algorithm and an encryption key. The algorithm code and the key will both
be encrypted with a standard public key encryption algorithm (such as PGP)
using both the service's public key and the device manufacturer's private
key. One encryption algorithm code will specify that no encryption will be
used. An unrecognized encryption identification code is an error.
If a symmetric encryption algorithm is specified, it will be used for the
remainder of the initialization process.
All data and codes described below are part of the content layer. When the
call description says that the device 11 will send a particular code or
datum, this means that the code or datum is first encrypted, then encoded
for error detection, then modulated, then transmitted.
The device 11 next sends its ESN, and a three-character code identifying
the device type. This device type code will allow the protocol to be used
for specialized devices (with some standard features disabled or with
non-standard features added) as well as for the standard devices. An
unrecognized device type code is an error.
The next information the device 11 will send is a code indicating whether
the device 11 has already been assigned an SID and an MIN by a cellular
phone service provider. If an SID and an MIN have been assigned, the
device 11 will also send these numbers to the service 19. An illegal SID
or MIN is an error.
The service 19 will respond (using the specified encryption algorithm and
key) by sending the device 11 an SID and an MIN (if the device does not
already have these), and sending primary and secondary telephone numbers
(which the device 11 may use to contact the service for subsequent
communication sessions).
The service 19 will then send a call termination code and terminate the
call.
In summary, for initialization the device 11 sends the following data to
the service 19:
1. Device manufacturer identification code (unencrypted).
2. Symmetric encryption algorithm identification code (using public key
encryption).
3. Symmetric encryption key (using public key encryption).
4. ESN (using symmetric encryption).
5. Code identifying device type (using symmetric encryption).
6. Cod indicating whether device has been assigned SID and MTN (using
symmetric encryption).
7. (If SID and MIN have been assigned) SID (using symmetric encryption).
8. (If SID and MIN have been assigned) MIN (using symmetric encryption).
The service 19 responds by sending the following data to the device:
9. (If SID and MIN have not been assigned) SID (using symmetric
encryption).
10. (If SID and MIN have not been assigned) MIN (using symmetric
encryption).
11. Primary telephone number for contacting service (using symmetric
encryption).
12. Secondary telephone number for contacting service (using symmetric
encryption).
When the initialization call has been successfully completed, the service
19 will call the device 11 and issue each legal instruction and data
request (defined below) to test the initialization and will instruct the
device 11 to call the primary and secondary phone numbers. If the
instruction and data requests are correctly received by the device 11, if
the data transmitted by the device are correctly received by the service
19, and if the primary and secondary phone numbers are successfully called
by the device 11 within 10 minutes, then the device 11 is initialized.
Otherwise the client 20 is notified that initialization failed.
Communication Protocol 12: Part 2--Communicating with an Initialized
Personal Location Device.
The physical communication channel layer is the cellular telephone network
and the telephone network between the cellular telephone service provider
and the location services physical location.
The link layer is an onboard modem using a standard low-level modulation
protocol such as V.34, V.32bis, V.32, V.22bis, or V.22.
For calls initiated by the service 19, the encryption/encoding layer will
be the symmetric encryption algorithm agreed upon during initialization,
and the service's error detecting algorithm. Calls initiated by the device
11 will begin with null-encryption and switch to the agreed-upon symmetric
encryption algorithm as soon as the service correctly acknowledges receipt
of a registered ESN. Device-initiated calls will use the service's
error-detecting algorithm throughout. An error in recognition of the
call-initiator (device or service) will require retransmission. After five
unsuccessful attempts, the call will be terminated. Other errors will
result in a single attempt to retransmit. If retransmission is
unsuccessful, the particular request, data transfer, or instruction will
be abandoned and the call will continue.
The procedure for re-establishing communication if a call is interrupted
before all tasks have been completed (a missing call-terminator code
error) is:
1. If a service-initiated communication session is interrupted before the
call-terminator is sent and acknowledged, the session will be re-initiated
by the service 19.
2. If a device 11 initiated communication session is interrupted before the
service 19 has acknowledged the device ESN, the device will re-initiate
the session.
3. If a device 11 initiated communication session is interrupted after the
service 19 has acknowledged the device ESN, but before the call-terminator
is sent and acknowledged, the service 19 will re-initiate the session.
The content layer consists of the instructions and data identified in the
following descriptions of calls.
Description of a service-initiated communication call. The service 19 may
initiate a call to poll the device 11 for its location (current and/or
past), to instruct the device 11 on appropriate time intervals or distance
intervals for saving past locations, or to toggle the device 11 between
standard and emergency states.
After modem handshaking has been completed, the service 19 will send a
signature and the device 11 will acknowledge that the signature is
genuine. Then the service 19 will send instruction codes and parameters
(where needed) to the device 11 and the device 11 will respond by sending
requested data or by acknowledging the instruction (if the instruction is
not a request for data). Data, commands, and acknowledgements are all
encrypted using the specified symmetric encryption algorithm, and coded
using the service's error-detecting algorithm.
The service 19 will send one instruction code and accompanying parameters,
wait for the device 11 to send data or acknowledgement, and then send the
next code and parameters. When all instructions have been send and acted
upon, the service 19 will send a code that terminates the session.
The set of instructions and parameters correspond to the entries in Table
1.
TABLE 1
Instruction/Parameter Set for Personal Location System.
Instruction Parameters Action
Send location None Send most recent latitude,
longitude, elevation, time of fix,
and number of satellites in fix.
Send past None Send latitudes, longitudes,
locations elevations, times, numbers of
satellites for all saved locations,
starting with the most recent.
Send battery None Send status of battery.
status
Set time Time interval Acknowledge receipt of interval
instruction, set interval of time
between saved locations.
Set distance Distance Interval Acknowledge receipt of
interval instruction, set interval of
distance between saved locations.
Set state New state Acknowledge receipt of instruction,
(emergency or set state of device.
standard)
Description of a primary device-initiated call--The device 11 initiates a
call to the primary phone number to notify the service 19 that the
device's battery is low.
After modem handshaking is completed, the device 11 will send its ESN using
public-key encryption with the service's public key. If the ESN is
properly registered (via initialization), the service 19 will respond by
sending the ESN back, encrypted using the symmetric encryption algorithm
and key specified when initializing the device.
Next the device 11 will send the latitudes, longitudes, elevations, times,
and numbers of satellites for the saved locations, starting with the most
recent. When the data has all been sent and received without error, the
service 19 will send a code to terminate the communication session.
Description of a secondary device-initiated call--The device 11 initiates a
call to the secondary phone number to alert the service that the device 11
carrier has pressed the panic button.
After modem handshaking is completed, the device 11 will send its ESN using
public-key encryption with the service's public key. If the ESN is
properly registered (via initialization), the service 19 will respond by
sending the ESN back, encrypted using the symmetric encryption algorithm
and key specified when initializing the device.
Next the device 11 will send the latitude, longitude, elevation, time, and
number of satellites for the most recent location. The service 19 will
acknowledge, and then the device 11 will await instructions from the
service 19. When appropriate, the service 19 will send a code to terminate
the session.
Delivery Service--The client 20 may contact the service 13 through any of
three modes: automated voice response system, a call center staffed by
human operators, or through a world-wide-website. The client 20 is led
through the same series of steps in any of the three modes. Each mode
implements security through the use of passwords. The world-wide-website
uses encryption to provide additional security. When calling
operator-staffed call center, the client 20 is first greeted by an
automated voice response system, but may opt out of the system (and into
the operator queue) at any point.
Call center operators access the software portions of the delivery service
13 through a local or wide area network or via the Internet, using either
a traditional client/server model or a web-browser/website model. Call
center operators typically do not know the identity of clients 20 they are
serving, nor do they know the clients' passwords or contact information.
If a client 20 opts to have the operator enter either the account number
or the password (rather than doing these through the automated voice
response system), the operator will necessarily discover these items, but
otherwise the call is anonymous unless the client 20 voluntarily discloses
information about his identity.
For account set-up and modification (contact information, billing plan,
password choice, etc.), the client 20 uses the world-wide-website or calls
an account service representative (who does not have access to any
information about the current or past locations of the remote location
devices). This separation of access to data (between call center operators
and account service representatives) assures confidentiality for those
clients 20 who require a high level of security.
Appendix 1 presents a flow diagram for a typical call to the call center to
request the current location of a remote location device 11. A request
submitted through the automated voice response system or through the
world-wide-website follows virtually the same flow, with obvious
modifications (for example, data sent to the operator's monitor would
instead be sent to the client's web browser, etc.). The following notes
clarify some points in the diagrams.
1. The software attempts to contact the remote location device 11 as soon
as it has enough information (if the clients' account has good or marginal
status). This will reduce waiting time for the client 20 if the client has
given the automated voice response system enough information to contact
the device 11 before going into the operator queue.
2. If the client 20 determines that an emergency exists, he may request
that the automated voice response system promote him to the head of the
operator queue.
3. If the client 20 has forgotten his password, a hint will be provided
(through any of the three access modes). If he has forgotten his account
number, it can be provided by an account service representative (or
through the world-wide-website).
4. If an account has marginal status (up to two months in arrears), the
service 19 will honor location requests, but the client 20 will be
referred to accounting afterward to discuss payment. If an account is more
than two months in arrears, its status is bad and location requests will
not be honored. The delivery serv | | |
