KIPS Transactions on Computer and Communication Systems (정보처리학회논문지:컴퓨터 및 통신 시스템)

Korea Information Processing Society (한국정보처리학회)
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Data Scrambling Scheme that Controls Code Density with Data Occurrence Frequency

데이터 출현 빈도를 이용하여 코드 밀도를 조절하는 데이터 스크램블링 기법

  • 현철승 (서울시립대학교 컴퓨터과학부) ;
  • 정관일 (서울시립대학교 컴퓨터과학부) ;
  • 유수원 (서울시립대학교 컴퓨터과학부) ;
  • 이동희 (서울시립대학교 컴퓨터과학부)
  • Received : 2021.02.03
  • Accepted : 2021.03.03
  • Published : 2021.09.30
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Abstract

Most data scrambling schemes generate pure random codes. Unlike these schemes, we propose a variable density scrambling scheme (VDSC) that differentiates densities of generated codes. First, we describe conditions and methods to translate plain codes to cipher codes with different densities. Then we apply the VDSC to flash memory such that preferred cell states occur more than others. To restrain error rate, specifically, the VDSC controls code densities so as to increase the ratio of center state among all possible cell states in flash memory. Scrambling experiments of data in Windows and Linux systems show that the VDSC increases the ratio of cells having near-center states in flash memory.

기존 데이터 스크램블링 기법은 랜덤한 코드를 생성한다. 이와 다르게 우리는 생성하는 코드의 밀도를 다르게 만드는 가변 밀도 스크램블링 기법을 제안한다. 먼저 코드 밀도를 다르게 만드는 조건과 방법에 대해 설명한다. 다음으로 가변 밀도 스크램블링 기법을 플래시 메모리에 적용하여 특정 셀 상태가 더 많이 발생하도록 한다. 특히 플래시 메모리의 에러율을 제한하기 위하여, 가변 밀도 스크램블링 기법은 코드의 밀도를 조절하여 모든 셀 상태 중 중간 상태를 가지는 셀 비율을 높일 수 있다. 윈도우즈와 리눅스 시스템의 데이터에 가변 밀도 스크램블링 기법을 적용하였으며, 실험 결과는 가변 밀도 스크램블링 기법이 중간과 가까운 상태를 가지는 셀의 비율을 증가시킴을 보여준다.

Keywords

Acknowledgement

This Research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education(2016009066).

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