Sign-Then-Encrypt Scheme with Cramer-Shoup Cryptosystem and
Dissanayake Digital Signature
Rahmad Bahri
1
, Mohammad Andri Budiman
2
and Benny Benyamin Nasution
3
1
Master of Informatics Program, Universitas Sumatera Utara, Medan, Indonesia
2
Faculty of Computer Science and Information Technology, Universitas Sumatera Utara, Medan, Indonesia
3
Politeknik Negeri Medan, Medan, Indonesia
Keywords:
Signcryption, Dissanayake, Cramer-Shoup, Running Time, Avalanche Effect.
Abstract:
Exchanging information in the era of Internet-based technology still has security violations such as disclosure,
modification, or destruction that make everyone worry about the exchange of information. The Dissanayake
digital signature is part of asymmetric cryptography based on the factorization of prime numbers and has
interesting mathematical properties. The property of such mathematics is that the sum of 2 odd numbers is a
multiple of 4. The Dissanayake digital signature does not generate signatures directly through messages. The
Cramer-Shoup algorithm is an asymmetric cryptographic algorithm that proved to be the first effective scheme
to withstand Adaptive Chosen Ciphertext Attack (ACCA) attacks compared to existing cryptographic systems.
The Cramer-Shoup algorithm is an extension algorithm of the Elgamal algorithm. This paper will implement
a sign then-encrypt scheme using Dissanayake digital signature and Cramer-Shoup algorithm and analyze
algorithms based on execution time and the avalanche effect. Based on simulation results, the characters’
length affects the execution time. The result of the process shows the length of the character linear with
execution time. From the results of the avalanche effect simulation, Dissanayake digital signature got the
average value of the avalanche effect of 51%, and the Cramer-Shoup algorithm got the average value of the
avalanche effect of 49%. Implementing the sign-then-encrypt scheme can maintain security by encrypting and
guaranteeing authenticity by adding a digital signature.
1 INTRODUCTION
Protecting data from disclosure, modification, or
destruction is essential in the development of to-
day’s technological era. The number of security
breaches that continues to increase makes everyone
who communicates through the global network (Inter-
net) worry about protecting their data. With the cur-
rent development of technology, computer security is
needed because computer security rests on confiden-
tiality, integrity, and availability (Stallings and Bauer,
2012; Manna et al., 2017). —many techniques in pro-
tecting data at this time by designing a sound com-
puter security system—can be used in cryptography
(Panhwar et al., 2019). Cryptography is a technique
that relies on mathematics to secure information such
as confidentiality, integrity, and entity authentication.
Confidentiality, integrity, and authenticity are the ba-
sic requirements of asymmetric cryptography (Abood
and Guirguis, 2018; Molk et al., 2021; Genc¸o
˘
glu,
2019).
Asymmetric cryptography, or public key cryptog-
raphy, has two keys (Public Key and Private Key)
used in the implementation process (Hossain et al.,
2013). In 1976, Whitfield Diffie and Martin Hellman
publicly introduced the concept of public key cryp-
tography (Lydia et al., 2021). Asymmetric crypto-
graphic algorithms use two keys to perform the en-
cryption and decryption process. Asymmetric cryp-
tography distributes public keys by publishing and
private keys stored by their owners or kept secret
(Khan et al., 2018; Maqsood et al., 2017).
Many security schemes have been implemented
by researchers in the field of cryptography, one of
which is signcryption, a scheme to achieve confiden-
tiality and authenticity (Elkamchouchi et al., 2018;
Kasyoka et al., 2021). In this case, confidentiality is
achieved by encryption schemes on asymmetric cryp-
tography, while authenticity can be achieved by digi-
tal signature schemes (Pandey, 2014),(Matsuda et al.,
2009).
One of the asymmetric cryptographic algorithms
Bahri, R., Budiman, M. and Nasution, B.
Sign-Then-Encrypt Scheme with Cramer-Shoup Cryptosystem and Dissanayake Digital Signature.
DOI: 10.5220/0012444900003848
Paper published under CC license (CC BY-NC-ND 4.0)
In Proceedings of the 3rd International Conference on Advanced Information Scientific Development (ICAISD 2023), pages 131-138
ISBN: 978-989-758-678-1
Proceedings Copyright © 2024 by SCITEPRESS – Science and Technology Publications, Lda.
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