Bing Wei, Ming Zhong, Qian Chen, Yi Wu^*, Yubin Li

CMC-Computers, Materials & Continua, Vol.86, No.2, pp. 1-20, 2026, DOI:10.32604/cmc.2025.069910 - 09 December 2025

Abstract In erasure-coded storage systems, updating data requires parity maintenance, which often leads to significant I/O amplification due to “write-after-read” operations. Furthermore, scattered parity placement increases disk seek overhead during repair, resulting in degraded system performance. To address these challenges, this paper proposes a Cognitive Update and Repair Method (CURM) that leverages machine learning to classify files into write-only, read-only, and read-write categories, enabling tailored update and repair strategies. For write-only and read-write files, CURM employs a data-difference mechanism combined with fine-grained I/O scheduling to minimize redundant read operations and mitigate I/O amplification. For read-write files,… More >

Chanhyeong Cho¹, Byeori Kim², Haehyun Cho², Taek-Young Youn^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.142, No.1, pp. 813-834, 2025, DOI:10.32604/cmes.2024.056952 - 17 December 2024

Abstract With the rise of remote collaboration, the demand for advanced storage and collaboration tools has rapidly increased. However, traditional collaboration tools primarily rely on access control, leaving data stored on cloud servers vulnerable due to insufficient encryption. This paper introduces a novel mechanism that encrypts data in ‘bundle’ units, designed to meet the dual requirements of efficiency and security for frequently updated collaborative data. Each bundle includes updated information, allowing only the updated portions to be re-encrypted when changes occur. The encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes, such… More >

Yifei Xiao, Shijie Zhou^*

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.1, pp. 169-185, 2023, DOI:10.32604/cmes.2022.021795 - 29 September 2022

Abstract To achieve the high availability of health data in erasure-coded cloud storage systems, the data update performance in erasure coding should be continuously optimized. However, the data update performance is often bottlenecked by the constrained cross-rack bandwidth. Various techniques have been proposed in the literature to improve network bandwidth efficiency, including delta transmission, relay, and batch update. These techniques were largely proposed individually previously, and in this work, we seek to use them jointly. To mitigate the cross-rack update traffic, we propose DXR-DU which builds on four valuable techniques: (i) delta transmission, (ii) XOR-based data More >

Taek-Young Youn¹, Nam-Su Jho^2,*

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 151-164, 2022, DOI:10.32604/cmc.2022.026653 - 18 May 2022

Abstract

Due to the development of 5G communication, many aspects of information technology (IT) services are changing. With the development of communication technologies such as 5G, it has become possible to provide IT services that were difficult to provide in the past. One of the services made possible through this change is cloud-based collaboration. In order to support secure collaboration over cloud, encryption technology to securely manage dynamic data is essential. However, since the existing encryption technology is not suitable for encryption of dynamic data, a new technology that can provide encryption for dynamic data is required

… More >