FIELD OF INVENTION
The present invention is in the field of pervasive tracking and monitoring of enterprise objects / assets.
Assets in an organization include humans, vericles, mobile objects, etc. Our invention is based on the
newly ratified technology of IEEE 802.15.4. The technology gives complete enterprise visibility and leads
to better management and better return on investments to organizations. The tracking and monitoring
of objects are made through the deployment of a wireless mesh network. In this invention, we show
how an object/actuator is controlled remotely in the PervCom's Real Time Tracking system. The tracking
system is enabled by the deploying of PervCorrI'S active wireless devices. The wireless devices consist of
three kinds; a wireless sink which has a wired connection to a computer, a wireless router and a wireless
tag. The objects that are to be tracked are attached with the wireless tags. For example, if we wish to
track the movement of humans in an area, tags are carried by them (humans). To know where the assets
are in the area, wireless routers are placed along important points of the area. Finally, the wireless sink
collects all the information and displays it on the computer to which it is connected by a wired
connection. Our current invention allows for a simple way to remotely control the tags. The tags can
also act as an actuator where it takes a particular action (like sounding of an alarm) when it is remotely
controlled. The system of the invention will have various types of end uses and applications involving
tracking and managing of mobile assets and people. For example, applications are in the automatic
control of sprinklers and other actuators in agiicultural Fields, tracking of the movement of persons in
sensitive and high risk zones, such as in mines to improve the safety of miners and mine equipment. This
improves the surveillance of the miners and tht; mine equipment and is of particular importance in the
event of an emergency and helps in mine rescue. The 1 racking applications are also present in the
management of a fleet of trucks in a campus th JS enabling the detection of unauthorized entry into the
campus or the movement of a truck in an unauthorized area of the campus. The system also has
applications in the hospital sector where the movement of doctors, nurses and patients will allow better
knowledge of their whereabouts. More critically, the system can track the location of hospital
equipment like oxygen cylinders, defibrillator tr.iys, first aid trays, mobile ECG machines etc. The system
has applications in other sectors like retail, whure the location of items in a warehouse are tracked, in
logistics, where we can track the movement of inventor/ from one warehouse to another, to have an
accurate picture of the amount of inventory left. Thus the system of the invention has numerous
industrial applications where it has the potential to provide accurate and real time information of the
location of the assets of the organization thus leading to better management and improved return on
investment.
BACKGROUND ART
It is well known in the art that from time to time tracking and monitoring systems have been made
available. Some of the well known and presently available systems of such remote tracking and
monitoring are discussed hereunder.

Standard Wi-Fi (IEEE 802.11) networks have been used to provide location tracking using customer
deployed Wi-Fi hotspots. Aeroscout is a cominercial provider of such a system and offers indoor and
outdoor real-time asset location, long range active RFID, choke point visibility and telemetry. A similar
offering is provided by Ekahau where the core of the tracking solution is based on commercially
available Wi-Fi networks. In both systems, iictive tags are essentially small IEEE 802.11 compliant
wireless devices. These tags are attached to equipment or carried by people for real time tracking. The
location of a tag is based on location of the Wi-Fi hotspots.
The above related works are based on the IEEE standard of 802.11 (Wi-Fi). Further, the solutions expect
a customer deployed Wi-Fi mesh network is already in place. Using the Wi-Fi standard has severe
restrictions as elaborated subsequently. In hazardous areas like the mines, safety precautions are
mandatory, such as, the output power of the devices should be restricted to within 1 watt and the
devices must be intrinsically safe. Restricting the output power restricts the effective range of the Wi-Fi
devices. Further, the Wi-Fi devices consume high power and it is therefore impractical and infeasible to
run such devices on small batteries like that of size AA.
Another restriction on the solution provided by already deployed Wi-Fi hotspots is that the multi hop
communication is not possible. Therefore, such systems expect the hotspots to be the last mile of a
traditional wired connection where data from the hotspot can then exploit the wired connection to
reach the intended destination. This aspect is severely restrictive in new deployments where there have
been no prior communication networks. For example, in deployments in mines, it is infeasible to deploy
an additional wired network to support the Wi-Fi hotspots Not only is this prohibitive in terms of cost, it
also puts a burden on the power requirements.
A further restriction of the competing solution; is that they provide no support for the deployment of
Wi-Fi Hotspots. In all these solutions it is assuned that the customer has already placed the hotspots.
This is impractical, as the efficient placement ol the hotspots will determine the efficacy of the tracking
and the wireless coverage of the solution.
OBJECTS OF THE INVENTION
It is thus the basic object of the present invention to provide a simple and reliable scheme for the
remote control of mobile wireless tags and actuators. The wireless tags and actuators are manufactured
by us (Pen/Com Consulting) and are IEEE 802.15 4 compliant.
Another object of invention is the reliable service guarantee for the remote control of the tags. Our
innovative way makes the controlling of remote tags reliable and error free.
Another object of invention is the controlling of remote tags and actuators through the internet thus
realizing the internet of things paradigm.

DETAILS OF THE INVENTION
In this present invention we develop a simple approach to the remote control of tagged objects. The
system of real time tracking involves a wireless mesh network made by devices of PervCom Consulting
deployed in the area where the movement of the assets need to be tracked. The location of the asset
(which carries the wireless tag) is made based on the location of the wireless router. Therefore, the
system reports statements such as: tag El is located at router Rl. Since the wireless routers are placed
apriori, their location are well known. The remote control of the tags must be made possible over the
internet. The wireless mesh network is pictorially depicted in figure 1.
The remote control of wireless tags involves the solving of three aspects. Firstly, we need to formulate a
mechanism where a command sent from the sink (which is connected to a computer via a wired
connection) is able to make its way to the correct tag. Things to note at this juncture are that the tag is
mobile, i.e. a tag El can be at router Rl when the message is sent at the sink. However, the tag could
move to another router while the command is in transit. Therefore, we need a way to ensure the
command is able to reach the correct tag as fast as possible. This, we term as the routing challenge. The
second issue involves the reliable delivery of the command. For example, the wireless tag may be out of
range for some time, or it could be in a low power mode where it cannot receive messages. In such a
scenario, we must be able to ensure the command once sent from the sink, reaches the intended tag
with a near 100% guarantee. We also need to ensure that the radio profile of the medium which can
result in the loss of packets in communication does not affect the reliability of the transfer of the
command. This factor, we term as the reliability challenge. Finally, the third issue, we solve is to make
this remote control achievable over the internei. Thus we must be in a position, where sitting thousands
of kilometers away, we can still remotely control a wireless tag. This we term as the Internet challenge.
a) The Routing Challenge
The wireless tag could be located at any router at any given instant of time. Our system keeps the same
MAC (medium access control) address for every tag. The MAC address is the mechanism used to identify
the tag. For example, if a wireless tag has a MAC address of OxOA, then it would respond to only those
frames which have their destination address a: OxOA. All other frames will be discarded. The wireless
mesh network built by our system is a hierarchical tree in topology. The sink is the root of the network
and the tags form the leaves of the network. The hierarchical tree implies there is only one way to reach
every wireless router and thus only one way in which the tag can be reached. Thus, while the formation
of the network, every device stores the addresses of its children and the address of its parent. Note that
in a hierarchical tree, every node (except the sink) has a single parent. When a packet (that contains the
command) is generated at the sink for a particular tag, the sink forwards the packet to its every child.
Similarly, every child forwards the packet to each of their respective children. In this way, the entire
network is made aware of the command and wherever the tag is located, it receives the command.
Thus, no special handling of the routing is needed to account for the movement of the tag, once the
command is generated at the sink to the time it is delivered at the tag. This mechanism is extremely

simple and avoids the formation of an overhead in terms of continuous forward of the same packet,
since the network is hierarchical and a node can be reached only by one way. Therefore, duplicate
packets do not arrive at any given node and the broadcast storm problem does not occur. The
mechanism is depicted in figure 2.
b) The Reliability Challenge
The reliability is achieved in two stages. When a particular node (the wireless sink or the wireless router)
receives the command which it is supposed to forward to every child (refer to (a)), it first saves the
command to its memory and then forwards the command. The command is saved for a finite amount of
time. When a particular tag communicates with the node (to inform its location), the node forwards the
command saved to the tag and deletes the saved message. Thus, when a command is sent by the sink, it
is saved by the entire network for a finite amount of time. The wireless tag spends most of its time in a
low power mode (sleep state). In this way it conserves energy and is able to last on small batteries for a
long amount of time. When a tag periodically comes out of the low power state, it sends its identity
packet to the nearest wireless router. The wireless router can now determine the location of the tag and
it forwards the saved command to the tag. The saved command has a command ID. The tag checks if the
command ID is greater than the last performed command and if so, it executes the command. The
command could be to turn on an external buzzer, a light, etc. This in effect is the remote control. Upon
successful completion of the command, the tag sends an acknowledgement packet to the sink. If the
sink does not receive the acknowledgement packet from the tag, it will re generate the command again.
In this way, the reliability of the command is ensured by using two complementary mechanisms (the
command save and the command acknowledgement). This is depicted in figure 3.
c) The Internet Challenge
The remote control of tags must be achieved over the internet. This is achieved by having a protocol
converter at the sink. The sink connects to the internet using the wired connection to the computer. A
proprietary application is hosted on the computer and this application does two particular functions.
One, it has the appropriate constructs to display pictorially the location of the tags with respect to that
of the wireless routers. It also hosts the display in a formal: that is made possible to be viewed from the
internet. This is pictorially shown in figure 4.
Thus, the present invention shows how the remote control of tags is made possible in our proprietary
system. We achieve remote control of tags whi< h are mobile and achieve neat 100% reliability. Further,
the remote control is made possible from the iniernet.

BRIEF DESCRIPTION OF ACCOMPANYING FIGURES
Figure 1: is a representative depiction of a wireless mesh network. It shows the multi-hop propagation
of messages from the source to the destination (sink).
Figure 2: shows how the routing challenge for send the command to a mobile tag is solved.
Figure 3: shows how the reliability of the commands sent is achieved.
Figure 4: shows how the remote control of the tags is achieved from the internet and the representative
protocol converter.

WE CLAIM:
1. A simple and reliable scheme for the remote control of mobile wireless tags and actuators in an
IEEE 802.15.4 compliant mesh netv/ork for real-time pervasive tracking, monitoring and
management system.
2. A unique way for reliable service guarantee for the remote control of the tags and actuators in
an IEEE 802.15.4 compliant mesh network for real-time pervasive tracking, monitoring and
management system.
3. An efficient way for achieving the remote control of tags and actuators over the internet in an
IEEE 802.15.4 compliant mesh network for real-time pervasive tracking, monitoring and
management system.

Our invention presents an easy and efficient method for the remote control of tags and actuators in an IEEE 802.15.4 compliant real time pervasive tracking, management and sensing system. Tags and actuators in such a system form the leaves of the wireless network. Our invention firstly organizes the mesh network as a hierarchical tree where every node (except the root) has only one parent. This ensures that there is a unique way to reach a node and duplicate paths do not exist. Using this property, we present the three objects of our invention where the routing for mobile tags, the reliability and achieving the remote control over the internet is solved Our invention allows a way in which, sitting thousands of kilometers away, the remote control of the tag can still be done reliably and efficiently. Through this invention, the management of mobile assets is made efficient. An application of our invention would allow for automatic control of actuators, like sprinklers in an agricultural field based on
the amount of moisture in the area or switching off the light of a room in your home from your office.