Digital Forensics in Small Devices: RFID Tag Investigation

These Class 4 tags are capable of not only initiating communication with the
reader, but also they can communicate with other tags. Class 5 tags, referred to as
the reader tag, have the same functionalities as that of Class 4, except they can
initiate communication with all classes of tags.
Hence, the main characteristics of different types and classes of RFID tags
are summarized as shown in Table 2.1.
2.1.2 RFID Transceiver or Reader
An RFID transceiver or reader (see Figure 2.5), sometimes referred to as an
interrogator, is a communication bridge between the tag and the host or controller.
A RFID transceiver consists of a transmitter and receiver. There is no need for a
line of sight scanning between the tag and the receiver in a RFID system; in the
same way the bar code system does (Hunt et al., 2007). The reader queries a tag
and received the data stored in the tag. The other parts of the reader include
“antenna (either integrated or a separate one), RS-232 serial port or Ethernet jack,
cryptographic encoding and decoding circuit, a power supply or battery and
communication control circuits” (Thornton et al., 2006, p. 16).
Figure 2.5: Handheld RFID reader (Source: http://www.prlog.org/10138875-
handheld-rfid-reader-dl8033-in-1356mhz.jpg)
Typically, RFID readers have the following basic functions, which are stated by
Hunt et al., (2007, p. 9):
“the readers read the contents of the data, write the data on the tag if
the tags are writable, transmit data to and from the host or controller,
and give power to the tags if the tags are passive”.
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