Distributed file systems questions (Ed)
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16. Coda provides server replication to increase availability in the
presence of network partitions and server crashes.  Assuming
partitions between servers are extremely rare, how could Coda be
simplified (in terms of replication and consistency mechanisms) while
still preserving availability during server crashes?













17. Coda and xFS provide a global name space (meaning that a name
refers to the same file from every client), while NFS and Plan 9 do
not.  What are the main advantages and disadvantages of providing a
global name space?












18. You are designing a file "sharing" system that lets people access
music files stored on a set of stationary servers from handheld
computers, via a low-bandwidth, high-latency, unreliable network.  For
each of the following design considerations, what would you choose,
and why?

(a) caching granularity (file, block, none)
(b) locking strategy (optimistic, pessimistic, none)
(c) server replication (file replicas, striping, none)
(d) security (server authentication, client authentication, access
control, encryption)