Marc A Shapiro

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Eventual consistency aims to ensure that replicas of some mutable shared object converge without foreground synchronisation. Previous approaches to eventual consistency are ad-hoc and error-prone. We study a principled approach: to base the design of shared data types on some simple formal conditions that are sufficient to guarantee eventual consistency. We(More)
Fragmented Objects (FOs) extend the object concept to a distributed environment. The abstract view of a FO is a single, shared object, of which the distribution is hidden to clients. In the concrete view the FO designer controls (if wished) the distribution of data and function and of the communication between fragments. FO programming is supported by the(More)
S S P c h a i n s a r e a n o v e l t e c h n i q u e f o r r e f e r e n c i n g o b j e c t s i n a d i s t r i b u t e d s y s t e m . T o c l i e n t s o f t w a r e , a n y o b j e c t r e f e r e n c e a p p e a r s t o b e a l o c a l p o i n t e r ; w h e n t h e t a r g e t i s r e m o t e , a n S S P c h a i n a d d s a n i n d e t e r m i n a t e(More)
optimistic, replication, survey Replication is a key enabling technology in distributed data sharing systems for improving both availability and performance. This paper surveys optimistic replication algorithms, which allow replica contents to diverge in the short term, in order to support concurrent work and to tolerate failures in low-quality(More)
SSP chains are a novel technique for referencing objects in a distributed system. To client software, any object reference appears to be a local pointer; when the target is remote, an SSP chain adds an indeterminate number of levels of indirection. Copying a reference across the distributed system extends an SSP chain at one end; migrating the target object(More)
The prostate cancer incidence and mortality of black Americans is among the highest in the world. The reasons have not been adequately explained. Similar disparities have been noted for men of sub-Saharan origin living in Brazil and the Caribbean. Avenues of investigation have assessed racial and ethnic differences in diet as well as possible differences in(More)
Developing write-sharing applications is challenging. Remote and offline data sharing are increasingly important. We propose a generic platform called Telex to ease development and to provide guarantees. Telex is driven by application semantics. Telex takes care of replication and persistence, drives application progress, and ensures that replicas(More)
Optimistic replication lets multiple users update local replicas of shared data independently. These replicas may diverge and must be reconciled. In this paper, we present a general-purpose reconciliation system for mobile transactions. The basic reconciliation engine treats reconciliation as an optimization problem. To direct the search, it relies on(More)