RFID Authentication Protocols using Symmetric Cryptography

by Boyeon Song

RHUL-MA-2009-24

Abstract:

Radio Frequency IDentification (RFID) is emerging in a variety
of applications as an important technology for identifying and
tracking goods and assets. The spread of RFID technology,
however, also gives rise to significant user privacy and
security issues. One possible solution to these challenges is
the use of a privacy-enhancing cryptographic protocol to
protect RFID communications.

This thesis considers RFID authentication protocols that make
use of symmetric cryptography. We first identify the privacy,
security and performance requirements for RFID systems. We then
review recent related work, and assess the capabilities of
previously proposed protocols with respect to the identified
privacy, security and performance properties.

The thesis makes four main contributions. First, we introduce
server impersonation attacks as a novel security threat to RFID
protocols. RFID tag memory is generally not tamper-proof, since
tag costs must be kept low, and thus it is vulnerable to
compromise by physical attacks. We show that such attacks can
give rise to desynchronisation between server and tag in a
number of existing RFID authentication protocols. We also
describe possible countermeasures to this novel class of
attacks.

Second, we propose a new authentication protocol for RFID
systems that provides most of the identified privacy and
security features. The new protocol resists tag information
leakage, tag location tracking, replay attacks, denial of
service attacks and backward traceability. It is also more
resistant to forward traceability and server impersonation
attacks than previously proposed schemes. The scheme requires
less tag-side storage than existing protocols and requires only
a moderate level of tag-side computation.

Next, we survey the security requirements for RFID tag
ownership transfer. In some applications, the bearer of an RFID
tag might change, with corresponding changes required for the
RFID system infrastructure. We propose novel authentication
protocols for tag ownership and authorisation transfer. The
proposed protocols satisfy the requirements presented, and have
desirable performance characteristics.

Finally, we address the issue of scalability in anonymous RFID
authentication protocols. Many previously proposed protocols
suffer from scalability issues because they require a linear
search to identify or authenticate a tag. Some RFID protocols,
however, only require constant time for tag identification;
unfortunately, all previously proposed schemes of this type
have serious shortcomings. We propose a novel RFID pseudonym
protocol that takes constant time to authenticate a tag, and
meets the identified privacy, security and performance
requirements. The proposed scheme also supports tag delegation
and ownership transfer in an efficient way.