Consistency maintenance in a Distributed Diary for Mobile computers

02.07.2001

Abstract

We have presented a distributed diary system by describing relations between diaries, diary-clients, diary-servers, iCal-objects and users. In this thesis we have designed and implemented the part of a diary system called a diary-client, which has been our research vehicle for studying consistency maintenance within and between diaries. We have focused on mobile diary-clients, which often have limited storage space and network bandwidth available.

Our solution is based solely on direct communication between diary-clients because we want diary-clients to work independently of diary-servers. We have therefore explored how diary-clients may provide functionality to their users in situations where they are unable to connect to a diary-server.

Diary systems are different than some more traditional distributed systems, like file systems, because they deal with data, which is related to certain semantic rules File systems, on the other hand, must often deal with files containing arbitrary data. Our diary system uses standard iCalendar objects as data units. We believe that consistency can be easier maintained for diary systems, than for file systems, by taking advantage of the semantics included in iCalendar objects.