Differentiation Features of RFID Systems - RFID: Fundamentals and Applications in Contactless Smart Cards and Identification - page 26

Inductive coupling

Electromagnetic coupling
(backscatter) nondirectional

1 2 3 m

Electromagnetic coupling
(backscatter) directional

Figure 2.18 Comparison of the relative interrogation zones of different systems

The speed of transponders, relative to readers, together with the maximum write/read
distance, determines the length of time spent in the reader's interrogation zone. For
the identification of vehicles, the required range of the RFID system is designed such
that at the maximum vehicle speed the length of time spent in the interrogation zone
is sufficient for the transmission of the required data.

2.5.3 Security requirements

Security requirements to be imposed on a planned RFID application, i.e. encryption
and authentication , should be assessed very precisely to rule out any nasty surprises in
the implementation phase. For this purpose, the incentive that the system represents to
a potential attacker as a means of procuring money or material goods by manipulation
should be evaluated. In order to be able to assess this attraction, we divide applications
into two groups:

• industrial or closed applications;

• public applications connected with money and material goods.

This can be illustrated on the basis of two contrasting application examples.
Let us once again consider an assembly line in the automotive industry as a typical
example of an industrial or closed application. Only authorised persons have access
to this RFID system, so the circle of potential attackers remains reasonably small.
A malicious attack on the system by the alteration or falsification of the data on a
transponder could bring about a critical malfunction in the operating sequence, but the
attacker would not gain any personal benefit. The probability of an attack can thus be