Fifty-five percent of federal inmates are housed either in a camp or minimum security level facility. Only 11% are as you characterized max. Medium federal facilities are controlled movement, cells as opposed to dormitories or cubicles and interaction only on you walkway as opposed to going wherever you want as long as the yard is open, usually 10:00pm. If plenty of AK wind up in medium level the nature of the crime may compell that. Some examples are: armed bank robbery, continuing criminal enterprise, drug sentences of 20yrs and consecutive sentences of anything totalling 20 yrs or more. States will often relinquish prosecution to the feds for expense, ease of prosecution and conviction and federal 95% conviction ratio.