4.1 Basis of Designing Safe Electronic …
281
Before actual examination of hardware Trojans, it is necessary to understand their
principal differences from the software Trojans (implants) examined in Chap. 2.
Hardware Trojans:
– The Trojan is directly built into the microcircuit;
– After introduction, operation mode of the Trojan cannot be changed;
– A hardware Trojan is extremely difficult to identify: any modern microcircuit is
very similar to a black box.
Software Trojans:
– The Trojan is a part of a program code;
– The Trojan behavior can be externally changed;
– The Trojan is usually introduced via a computer network;
– Once detected, it can be deleted and saved in the data base, which will aid its
detection in the future.
Therefore, the most deliberate attention is drawn to the issue of hardware Trojans
among scientists, specialists, and, of course, special services community. According
to the generalized information obtained by the authors, over 500 articles on the
subject, including articles [1–111], were published only during the analyzed period
(2007–2017).
Figure 4.4a shows the growth dynamics of both reviews and specific publications
on this issue. For example, even though only one (first) review article and nine specific
b)
а)
■ *—Articles in total —■ —Articles excluding reviews
Trojan development —■ —Countermeasures —А—Review
Fig. 4.4 Number of publications dedicated to hardware Trojans (a); publications in the volume of
the subject (b)
281
Before actual examination of hardware Trojans, it is necessary to understand their
principal differences from the software Trojans (implants) examined in Chap. 2.
Hardware Trojans:
– The Trojan is directly built into the microcircuit;
– After introduction, operation mode of the Trojan cannot be changed;
– A hardware Trojan is extremely difficult to identify: any modern microcircuit is
very similar to a black box.
Software Trojans:
– The Trojan is a part of a program code;
– The Trojan behavior can be externally changed;
– The Trojan is usually introduced via a computer network;
– Once detected, it can be deleted and saved in the data base, which will aid its
detection in the future.
Therefore, the most deliberate attention is drawn to the issue of hardware Trojans
among scientists, specialists, and, of course, special services community. According
to the generalized information obtained by the authors, over 500 articles on the
subject, including articles [1–111], were published only during the analyzed period
(2007–2017).
Figure 4.4a shows the growth dynamics of both reviews and specific publications
on this issue. For example, even though only one (first) review article and nine specific
b)
а)
■ *—Articles in total —■ —Articles excluding reviews
Trojan development —■ —Countermeasures —А—Review
Fig. 4.4 Number of publications dedicated to hardware Trojans (a); publications in the volume of
the subject (b)