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In January 2013, the National Institute of Standards and Technology (NIST) announced the CAESAR (Competition for Authenticated Encryption: Security, Applicability, and Robustness) contest to identify authenticated ciphers that are suitable for a wide range of applications. A total of 57 submissions made it into the first round of the competition out of which 6 were announced as winners in March 2019. In the process of the competition, NIST realized that most of the authenticated ciphers submitted were not suitable for resource-constrained devices used as end nodes in the Internet-of-Things (IoT) platform. For that matter, the NIST Lightweight Cryptography Standardization Process was set up to identify authenticated encryption and hashing algorithms for IoT devices. The call for submissions was initiated in 2018 and in April 2019, 56 submissions made it into the first round of the competition. In August 2019, 32 out of the 56 submissions were selected for the second round which is due to end in the year 2021. This work surveys the 32 authenticated encryption schemes that made it into the second round of the NIST lightweight cryptography standardization process. The paper presents an easy-to-understand comparative overview of the recommended parameters, primitives, mode of operation, features, security parameter, and hardware/software performance of the 32 candidate algorithms. The paper goes further by discussing the challenges of the Lightweight Cryptography Standardization Process and provides some suitable recommendations.

Internet of Things (IoT) is an auspicious technology that will connect more number of devices through an internet. The huge number of communication expected to transmit high data securely is an important problem in recent days. In this paper, an Enhanced Energy Efficient Lightweight Cryptography Method which utilizes 8 bit manipulation principle (E3LCM) has been proposed. The proposed method has been verified for speech signal using MATLAB. The hardware complexity has been validated using Sparten3E XC3S500E FPGA devices and it has been found that the proposed method consumes 202mW power and 0.9 Kbytes RAM and it outperforms other methods.

암호 알고리즘은 많은 연산 자원을 요구하며 복잡한 수학적 원리를 통해 보안성을 가진다. 하지만 대부분의 사물인터넷 기기는 가용 자원이 한정적이며 그에 따라 연산 성능이 부족하다. 따라서 연산량을 적게 사용하는 경량암호가 등장하였다. 미국 국립표준기술연구소는 경량암호 표준화 공모전을 개최하여 경량암호의 원활한 보급을 꾀했다. 공모전의 알고리즘 중 하나인 TinyJAMBU는 순열 기반의 알고리즘이다. TinyJAMBU는 키 스케줄을 거치지 않는 대신 많은 순열 연산을 반복하며, 이때 시프트 연산이 주로 사용된다. 본 논문에서는 8-bit AVR 프로세서상에서 경량암호 TinyJAMBU를 고속 최적 구현하였다. 제안 기법은 시프트 연산을 반대 방향으로 하여 시프트 횟수를 최소화한 리버스 시프트 기법과 키와 논스가 고정인 환경에서 일부 연산을 사전 연산한 기법이다. 제안 기법은 순열연산에서 최대 7.03배, TinyJAMBU 알고리즘에 적용 시 최대 5.87배 성능 향상을 보였다. 키와 논스가 고정인 환경에서는 TinyJAMBU의 알고리즘이 최대 9.19배만큼 성능이 향상되었다.

Cryptographic algorithms require extensive computational resources and rely on complex mathematical principles for security. However, IoT devices have limited resources, leading to insufficient computing power. As a result, lightweight cryptography has emerged, which uses fewer computational resources. NIST organized a competition to standardize lightweight cryptography and TinyJAMBU, one of the algorithms in the competition, is a permutation-based algorithm that repeats many permutation operations. In this paper, we implement TinyJAMBU on an 8-bit AVR processor with a proposedtechnique that includes a reverse shift method and precomputing some operations in a fixed key and nonce environment. Our techniques showed a maximum performance improvement of 7.03 times in permutation operations and 5.87 times in the TinyJAMBU algorithm, improving up to 9.19 times in a fixed key and nonce environment.

SITM (See-In-The-Middle) 공격은 부채널 정보를 활용한 차분 분석 기법 중 하나로, CHES 2020에서 제안되었다. 이 기법은 부분적으로 부채널 마스킹이 적용된 블록암호에서 부채널 마스킹이 적용되지 않은 중간 라운드의 전력 파형을 이용해 차분 분석을 진행한다. 블록암호 GIFT는 CHES 2017에 제안된 경량암호로, 블록암호 PRESENT에서 발견된 취약점을 보완하고 더욱 효율적인 구현이 가능하도록 설계되었다. 본 논문에서는 부분 마스킹이 적용된 GIFT-128에 대한 SITM 공격을 제안한다. 이 공격은 4-라운드와 6-라운드 부분 마스킹이 적용된 GIFT-128을 공격대상으로 하며, 공격에 필요한 시간/데이터 복잡도는 각각 2^14.01 /2^14.01, 2¹⁶ /2¹⁶ 이다. 본 논문에서는 SITM 공격에서 사용 가능한 마스터키 복구 논리를 비교하여, 상황에 따라 더욱 효율적인 논리를 선택하는 기준을 성립한다. 마지막으로, NIST 표준 경량암호 공모사업 최종 후보 중 하나인 GIFT-COFB에 해당 공격을 적용하는 방안을 제시한다.

The SITM (See-In-The-Middle) proposed in CHES 2020 is a methodology for side-channel assisted differential cryptanalysis. This technique analyzes the power traces of unmasked middle rounds in partial masked SPN block cipher implementation, and performs differential analysis with the side channel information. Blockcipher GIFT is a lightweight blockcipher proposed in CHES 2017, designed to correct the well-known weaknesses of block cipher PRESENT and provide the efficient implementation. In this paper, we propose SITM attacks on partial masked implementation of GIFT-128. This attack targets 4-round and 6-round masked implementation of GIFT-128 and time/data complexity is 2^14.01 /2^14.01, 2¹⁶ /2¹⁶. In this paper, we compare the masterkey recovery logic available in SITM attacks, establishing a criterion for selecting more efficient logic depending on the situation. Finally, We introduce how to apply the this attack to GIFT-COFB, one of the finalist candidates in NIST lightweight cryptography standardization process.

This paper proposes a new lightweight cipher VAYU. VAYU has a balanced Feistel structure. VAYU cipher supports 64 bit plaintext and 128/80 bit key length and it has a total of 31 rounds. It needs only 1290 GEs for 128 bit key length. It also results in minimal memory size as compared to all other existing lightweight ciphers. This paper discusses the security analysis of VAYU cipher design which is adequate against linear and differential cryptanalysis, Biclique attack, zero correlation attack, algebraic attack. VAYU cipher design will be best suitable for applications like IoT, smart Wireless Sensor networks. VAYU cipher uses two F-functions with substitution box, which results in a high diffusion mechanism.

Pervasive computing is the emerging field that needs ultra lightweight secure designs. In this paper, we have proposed a robust hybrid structure by fusion of RECTANGLE, LED and SPECK. With the help of a hybrid design, we have improved the key scheduling aspect of LED and related key attacks which were neglected in the LED cipher. In this paper, we also aimed at providing robust architecture by reducing footprint area to as less as possible. By using the S-box of RECTANGLE and the bit slicing technique, clustering of linear and differential trails are avoided which also strengthens the cipher. S-box of RECTANGLE is perfectly interfaced with LED design as their combination results in a differential path probability which is has an upper bound of 2-50 in its first round. The use of Bit slicing technique in this hybrid design results in good differential and linear properties, which provide resistance to cache and timing attacks. LED cipher which uses S-box of PRESENT results in clustering of linear and differential trails as S-box of PRESENT is specifically designed for compact hardware implementation. Column wise substitution and robust S-box design of RECTANGLE will make LED design robust and secure and enables it to provide resistance against any type of attack. SPECK which is designed by NSA has compact key scheduling and is best suited for our hybrid design, which helps in improving key scheduling of LED. In this paper, we have introduced a novel approach for robust design by amalgam of S-box of RECTANGLE & LED structure, and key scheduling by SPECK. This hybrid cipher design is secure against linear and differential cryptanalysis.

RC 무선조종기를 통해 드론을 원격으로 제어하는 경우, 제어 데이터의 기밀성과 무결성은 드론 제어권 탈취 방지를 위한 핵심 고려 사항이다. 본 논문은 드론 RC 무선조종기 제어 데이터 보호를 위해 경량 암호화 알고리즘 중 하나인 Lightweight Encryption Algorithm (LEA)를 적용하는 방법을 제시한다. LEA 는 32 비트 마이크로 컨트롤러인 ARM Cortex-M4 와 같은 플랫폼에 최적화된 구조로, 저전력으로 데이터 보호를 유지하면서 효율적인 암호화 알고리즘을 적용할 수 있다.

미국 국립표준기술연구소는 사물 인터넷 환경 상에서 원활하게 구동할 수 있는 경량암호의 표준화 공모전을 개최하였다. 경량암호 표준화 공모전은 2019년 Round 1 결과가 발표되었고, 2021년에는 최종 라운드 후보를 발표하였다. 최종 선정된 알고리즘은 총 10종이다. 선정된 알고리즘은 동작 방식에 따라서 순열 기반, 블록암호 기반, 트위커블 블록암호 기반, 그리고 스트림 암호 기반으로 분류된다. 또한 필수적으로 AEAD 기능을 제공할 것을 요구하며, 추가적으로 해시 기능을 제공하기도 한다. 본 논문에서는 국립표준기술연구소에서 진행한 경량암호 표준화 공모전의 최종 라운드에 대해서 확인해본다.

화이트박스 암호는 룩업 테이블 안에 키를 안전하게 숨기는 방법으로 메모리 접근 및 수정이 가능한 화이트박스 공격에 대응할 수 있다. 그러나, 룩업 테이블의 크기가 크고 암호화 속도가 느리기 때문에 IoT(Internet of Things) 기기같이 자원이 제한되어 있으면서도 실시간성이 필요한 장치에는 적용이 어렵다. 본 연구에서는 화이트박스 암호가 룩업 테이블 크기 기준으로 암호화를 처리하는 특성을 활용하여 짧은 길이의 평문을 모아서 한 번에 처리하는 방안을 제안한다. Chow와 XiaoLai 방식의 테이블 크기를 각각 720 KB(Kilobytes), 18,000KB로 가정한 제안 방식을 기존 방식과 비교한 결과, 메모리 사용량은 Chow와 XiaoLai 방식에서 평균 약 29.9%, 약 1.24% 감소하였다. 시간 지연도는 15Mbps(Mega bit per second) 이상의 트래픽 로드 속도일 때, Chow와 XiaoLai 방식에서 각각 평균 약 3.36%, 약 2.6% 감소하였다.

White-box cryptography can respond to white-box attacks that can access and modify memory by safely hiding keys in the lookup table. However, because the size of lookup tables is large and the speed of encryption is slow, it is difficult to apply them to devices that require real-time while having limited resources, such as IoT(Internet of Things) devices. In this work, we propose a scheme for collecting short-length plaintexts and processing them at once, utilizing the characteristics that white-box ciphers process encryption on a lookup table size basis. As a result of comparing the proposed method, assuming that the table sizes of the Chow and XiaoLai schemes were 720KB(Kilobytes) and 18,000KB, respectively, memory usage reduced by about 29.9% and 1.24% on average in the Chow and XiaoLai schemes. The latency was decreased by about 3.36% and about 2.6% on average in the Chow and XiaoLai schemes, respectively, at a Traffic Load Rate of 15 Mbps(Mega bit per second) or higher.

IoT (Internet of Things) 시대가 활성화되면서 개인정보를 포함한 많은 정보들이 IoT 디바이스들을 통해 전달되고 있다. 정보보호를 위해 디바이스끼리 상호 암호화하여 통신하는 것이 중요하며 IoT 디바이스 특성상, 성능의 제한으로 인해 경량 보안 프로토콜 사용이 요구된다. 현재 보안 프로토콜에서 사용하는 암호 기법들은 대부분 RSA, ECC (Elliptic Curve Cryptography)를 사용하고 있다. 하지만 고사양의 양자 컴퓨터가 개발되고 쇼어 알고리즘을 활용한다면 앞선 RSA와 ECC가 근거하는 안정성의 문제를 쉽게 해결할 수 있기 때문에 더 이상 사용할 수 없다. 이에 본 논문에서는 양자 컴퓨터의 계산능력에 내성을 가지는 보안 프로토콜을 설계하였다. 미국 NIST (National Institute of Standards and Technology) 양자내성암호 표준화 공모전을 진행중인 코드기반암호 ROLLO를 사용하였으며, IoT 디바이스끼리의 상호 통신을 위해 연산 소모가 적은 해시, XOR연산을 활용하였다. 마지막으로 제안하는 프로토콜과 기존 프로토콜의 비교 분석 및 안전성 분석을 실시하였다.

As the IoT (Internet of Things) era is activated, a lot of information including personal information is being transmitted through IoT devices. For information protection, it is important to perform cryptography communication, and it is required to use a lightweight security protocol due to performance limitations. Currently, most of the encryption methods used in the security protocol use RSA and ECC (Elliptic Curve Cryptography). However, if a high performance quantum computer is developed and the Shor algorithm is used, it can no longer be used because it can easily solve the stability problems based on the previous RSA and ECC. Therefore, in this paper, we designed a security protocol that is resistant to the computational power of quantum computers. The code-based crypto ROLLO, which is undergoing the NIST (National Institute of Standards and Technology) post quantum cryptography standardization, was used, and a hash and XOR computation with low computational consumption were used for mutual communication between IoT devices. Finally, a comparative analysis and safety analysis of the proposed protocol and the existing protocol were performed.

Using carefully assembled sets of IDs based on the cryptographic principle of secret shares, we can create RFID tags that yield virtually no information to casual "hit-and-run" attackers, but only reveal their true ID after continuous and undisturbed reading from up-close something that can hardly go unnoticed by an item's owner. In this paper, we analyses the practical issues of cryptography for RFID privacy with lightweight method.