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3 Hardware Trojans in Electronic Devices
The frequency bandwidth of the detection circuit signals is within 0.2–10 Hz, which
makes a failure impossible.
The top part of the SAFE-MAN plugin contains the additional interface, to which
a standard charger or an external battery can be connected. However, there are no
limitations in relation to the work time of the device (it stationary applications, at
least); the only problem here is that the internal battery will discharge over time in
case of the power network failure.
In addition to the aforementioned automatic control over the operation of the
processor using the watchdog timer, the data from the sensors are checked for compliance with various authenticity criteria. For example, it is possible that the infrared
sensor will react to an insect passing nearby, or that a child care device will be activated by a passing car, and the sleeping child will be awakened by the melody of the
music clock!
After sending an alarm system, new activation of the alarm state is only possible
15 min after the previous one. As an additional means of protection, it is possible to
protect all access forms with a four-character numeric code. This secret number is
programmed remotely and cannot be read as it is not stored in the mobile phone.
After connection of any plugin, all tone signals of a call will be switched off. They
are switched back on in manual mode in order for the mobile phone to ring when
called.
Let us consider the structure of the system response message using the plugin
SAFE-MAN (Fig. 3.9) as an example. Here, all important information about the
state of the system is given in nine lines.
The first two lines of a message usually contain the date, astronomic time, and
mobile number of the phone sending the message. The third line indicates whether
the transmitted command was executed successfully or with a mistake. It also can
contain the data on the new updated message.
Fig. 3.9 Structure of the
response SMS message
3 Hardware Trojans in Electronic Devices
The frequency bandwidth of the detection circuit signals is within 0.2–10 Hz, which
makes a failure impossible.
The top part of the SAFE-MAN plugin contains the additional interface, to which
a standard charger or an external battery can be connected. However, there are no
limitations in relation to the work time of the device (it stationary applications, at
least); the only problem here is that the internal battery will discharge over time in
case of the power network failure.
In addition to the aforementioned automatic control over the operation of the
processor using the watchdog timer, the data from the sensors are checked for compliance with various authenticity criteria. For example, it is possible that the infrared
sensor will react to an insect passing nearby, or that a child care device will be activated by a passing car, and the sleeping child will be awakened by the melody of the
music clock!
After sending an alarm system, new activation of the alarm state is only possible
15 min after the previous one. As an additional means of protection, it is possible to
protect all access forms with a four-character numeric code. This secret number is
programmed remotely and cannot be read as it is not stored in the mobile phone.
After connection of any plugin, all tone signals of a call will be switched off. They
are switched back on in manual mode in order for the mobile phone to ring when
called.
Let us consider the structure of the system response message using the plugin
SAFE-MAN (Fig. 3.9) as an example. Here, all important information about the
state of the system is given in nine lines.
The first two lines of a message usually contain the date, astronomic time, and
mobile number of the phone sending the message. The third line indicates whether
the transmitted command was executed successfully or with a mistake. It also can
contain the data on the new updated message.
Fig. 3.9 Structure of the
response SMS message