The PASIS project is building survivable storage systems and developing
an engineering understanding of the associated trade-offs.
PASIS is a survivable storage system. Survivable storage systems can
guarantee the confidentiality, integrity, and availability of stored
data even when some storage nodes fail or are compromised by an intruder.
Some such systems also offer user anonymity. Survivable storage systems
build on decentralized storage systems by encoding and distributing
data across many storage nodes. Thus, key design decisions center on
how data is encoded and distributed, and these decisions dictate the
performance, security, and availability guarantees offered by the system.
There is an inherent trade-off amongst security, availability, and
performance in a survivable storage system. In the PASIS project, we
are building a general survivable storage system that enables us to
experiment with many different mechanisms for data encoding and distribution.
Using this platform, we are developing models of the performance, security,
and availability of stored data. These models will enable us to perform
an engineering analysis and identify which encoding and distribution
schemes best meet the overall requirements for a particular storage
Greg Ganger (www)