3a312c46_tal_Commodities___Bitcoin_Wiki__Ideal_Implementation
[Property] Speed B [Notes] For large values, bitcoin is fast enough only for shipments; anything faster than an hour on average requires compromising security. For small transactions, bitcoin can be practically considered instantaneous since the security risks from an unconfirmed transaction are low [Ideal Implementation] 
ideally transactions would be instantaneous
Ideal Properties of Digital Commodities - Bitcoin Wiki
Ideal Implementation