| dc.description.abstract | In recent years, Internet of Things (IoT) has been a hot topic; it
has attracted much research attention and has promising market
prospects. IoT can be used to connect real world objects to the Internet,
and thus creates novel applications, such as home care, smart cities,
and smart factories. With the increasing adoption of IoT applications,
the security of IoT data transmission is more and more important.
Moreover, many IoT systems exchange data via wireless communications.
Hackers are thus easy to intercept information to launch attacks. The
encryption and decryption techniques of cryptosystems are applied to
tackle the IoT security issues. The techniques are classified into two
kinds: symmetric techniques and asymmetric techniques. Symmetric
techniques use the same key to encrypt and decrypt data exchanged
between devices. Asymmetric techniques use a pair of a public key and
a private key to encrypt and decrypt data. Symmetric techniques have
lower computation costs, but the distribution and management of keys
are difficult for this kind of techniques. Asymmetric techniques have
higher computation costs, but the public keys can be publicly
distributed without leaking the system secrets. Moreover, they can be
used to achieve digital signatures. This study is to improve the
asymmetric Rabin cryptosystem for applying it to the IoT to resist the
chosen ciphertext attack by duplicating the last few plaintext bytes
of an arbitrary length that is within a fixed range. Moreover, this
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study utilizes the fact that the computation costs of encryption and
decryption are also asymmetric in the Rabin cryptosystem. IoT devices
with limited resources encrypt/decrypt data with lower computation,
while devices with adequate resources encrypt/decrypt data with higher
computation costs. The improved Rabin system is to endow the IoT with
the properties of privacy, integrity, non-repudiation and
authentication. | en_US |