?이동 컴퓨팅 환경에서 캐쉬 관리를 위한 TWB 기법

Trickle Write-Back Scheme for Cache Management in Mobile Computing Environments

  • 김문정 (성균관대학교 전기전자및컴퓨터공학부) ;
  • 엄영익 (성균관대학교 전기전자및컴퓨터공학부)
  • 발행 : 2000.01.15

초록

최근 사용자가 위치를 이동하는 도중에도 네트워크에의 연결을 계속해서 유지할 수 있도록 하는 이동 컴퓨팅 환경에 대한 연구가 이루어지고 있다. 이러한 이동 컴퓨팅 환경을 위해 설계되고 구현되어야 할 요소 중의 하나가 이동 호스트를 고려한 분산 화일 시스템이며 이에는 여러 가지 설계 사항들이 존재한다. 이러한 설계 사항들 중에는 제한된 대역폭 상에서의 통신량 문제와 공유 화일에 대한 여러 사용자들의 수정 충돌(update conflict)로 인하여 발생되는 데이타 일치성 문제가 있다. 본 논문에서는 이동 컴퓨팅 환경에서 이동 클라이언트의 캐쉬 관리를 위하여 약한 연결상태를 이용하는 TWB(Trickle Write-Back) 기법을 제안한다. 본 제안 기법은 불필요한 write-back을 지연시키되 일정시간마다 중간 상태를 write-back 함으로써, 이동 컴퓨팅 환경에서 중요한 자원인 대역폭을 절약함과 동시에 그로 인한 디스크 낭비와 단절 상황 시에 발생될 위험 부분을 축소하도록 한다. 또한 기존의 분산 화일 시스템 구조를 충분히 이용하면서 사용자에게는 가능한 한 투명성을 제공한다.

Recently, studies on the mobile computing environments that enable mobile hosts to move while retaining its network connection are in progress. In these mobile computing environments, one of the necessary components is the distributed file system supporting mobile hosts, and there are several issues for the design and implementation of the shared file system. Among these issues, there are problems caused by network traffic on limited bandwidth of wireless media. Also, there are consistency maintenance issues that are caused by update-conflicts on the shared files in the distributed file system. In this paper, we propose TWB(Trickle Write-Back) scheme that utilizes weak connectivity for cache management of mobile clients. This scheme focuses on saving bandwidth, reducing waste of disk space, and reducing risks caused by disconnection. For such goals, this scheme lets mobile clients write back intermediate states periodically or on demand while delaying unnecessary write-backs. Meanwhile, this scheme is based on the existing distributed file system architecture and provides transparency.

키워드

참고문헌

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