A garbage detection protocol for a realistic distributed object-support system

We present a new protocol for the distributed detection of garbage, suitable for a low-level distributed object-support system. It is based on realistic assumptions: messages may be lost or duplicated; sites may crash; an object may migrate or be deleted. The protocol uses only information local to each site, or exchanged between pairs of sites; no global mechanism is necessary. It is parallel and should scale to extremely large systems. It takes into account the objectnding protocol. Its interface is designed for maximum independence from other components. R esum e Nous pr esentons un nouveau protocole pour la d etection r epartie des miettes. Il se prête a une mise en uvre au niveau syst eme. Il se base sur des hypoth eses r ealistes : un message peut se perdre ou être dupliqu e ; un site peut crasher ; un objet peut migrer ou être e ac e. Ce protocole n'utilise que des informations locales a un site, ou echang ees entre deux sites ; aucun m ecanisme global n'est n ecessaire. Il est parall ele et se prête a des syst emes de tr es grande echelle. Il tire parti des autres composantes du syst emes, comme le protcole de recherche des objets. Son interface permet une grande ind ependance entre composantes.

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