Peer-to-peer systems typically depend on untrusted and volatile computer systems for most of their resources. Trust is a social phenomenon with technical consequences. Volatility (i.e. unpredicatable availability) also is often due to human actions. Elaborate your answers by discussing the possible ways in which each of them is likely to differ according to the following attributes of the computers used:

i) ownership

ii) geographic location

iii) network connectivity

iv)country or legal jurisdiction

What does this suggest about policies for the placement of data objects in a peer-to-peer storage service?

ownership The owner of a computer is likely to act in a manner that maximizes his benefit, regardless of the fact that some of its resources are shared by others. The notion of trust is relative to ownership, so actions of type (b) or even (c) may be classified as acceptable.

geographic location Computers are subject to events of type (a) according to their geographic location.

network connectivity Portions of a network may become separated, making communication between them impossible. This might enable the owners in a disconnected portion to act against the interest of the majority.

country or jurisdiction The affects the ‘freedom of speech’ issue since governments or courts may persecute the owners of information or order the deletion of data. The latter can be addressed by ensuring that there are replicas in several countries/jurisdictions.