A request-reply protocol is implemented over a communication service with omission failures to provide at-least-once RMI invocation semantics. In the first case the implementor assumes an asynchronous distributed system. In the second case the implementor assumes that the maximum time for the communication and the execution of a remote method is T. In what way does the latter assumption simplify the implementation?

What will be an ideal response?

In the first case, the implementor assumes that if the client observes an omission failure it cannot tell whether it is due to loss of the request or reply message, to the server having crashed or having taken longer than usual. Therefore when the request is re-transmitted the client may receive late replies to the original request. The implementation must deal with this.

In the second case, an omission failure observed by the client cannot be due to the server taking too long. Therefore when the request is re-transmitted after time T, it is certain that a late reply will not come from the server. There is no need to deal with late replies