BLOCKING READER: DESIGN AND IMPLEMENTATION OF A ...

Blocking Reader uses inventory round of the protocol to its advantage. The
Blocking Reader transmits a serious of Query commands hence capturing the Tags.
The Tags reply to the query with an RN16 value but instead of acknowledging the Tag,
the BR transmit another Query command. Now the Tag assumes that the Reader
has not received the RN16. So it sends the RN16 again. This is done continuously
capturing the Tag. Blocking Reader uses a low-cost Reader architecture design. In
this thesis I present a different low-cost Reader architectures and implement BR in
the simplest low-cost Reader design.
1.4 Previous Work
Many have come up with different ways to provide privacy and security to the
RFID systems. Jules came up with a concept of Blocker Tag [24]. S.A. Weis proposes
several security mechanisms to make the Tags smarter [44].
1.4.1 Blocker Tag
Ari Juels proposes a simple blocker-tag scheme for privacy protection [24]. Here
blocker tags selectively exploit the tree-walking singulation protocol. Indeed his ap-
proach was to participate in the Tag communication in a non-compliant way causing
active jamming. Here the the approach is behaving like a Tag and sending a full
spectrum of serial numbers. Hence this process will obscure the serial numbers of
other Tags. This makes Readers hard to singulate Tags in the field. The blocker tag
when carried by a person induces a physical region of privacy protection around the
person.
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