security - SSL, Man in the Middle attack and caching of data transfers -

it possible store long periods of vast data transfers (ie. 1 month of communication in/out of whole country, continent etc.).

can ssl communication still considered safe in these circumstances?

i not security expert, wondering...

let communication between subjects involved (certification authority , both communicating entities) transferred on network being watched , data exchange stored somewhere. consider ca has not been breached (secure data stored in ca not leave ca, otherwise communication no longer safe).

is communication still secure?

how long take crack weak ssl certificate in case have data transferred on network available fastest supercomputer @ moment? (with short key, ie. 256bit ie. 100 pflops)

how long take 2048bit key in case have data transferred on network available?

thank answers, ready modify question if necessary (in case text / information needs modifying exact enough)

your question embodies contradiction in terms. can't have man-in-the-middle attack on stored session. man-in-the-middle attack occurs while connection up, , involves mitm posing peer both ends, requires certificate forgery. situation described in question concerns post-hoc decrypting of completed session, @ worst require brute-force iterating on possible keys, , feasibility halves every bit in key. these different attacks.