Q. What are two dreadful problems that designers should solve to implement a network-transparent system?
Answer: One such issue is making all the processors as well as storage devices seem transparent across the network. In other sense the distributed system must appear as a centralized system to users. The Andrew file system as well as NFS provides this feature the distributed file system appears to the user as a single file system however in reality it may be distributed across a network.
One more issue concerns the mobility of users. We want to permit users to connect to the "system" rather than to a specific machine (even though in reality they may be logging in to a specific machine somewhere in the distributed system).