How much faster is a T1 (1.5 Mbs) link vs. a 128Kbs link? Is it as simple as dividing one into the other which would equal roughly 11 times faster? What will this look like for the user who goes from 128K one day to a T! the next?
128 kbps is equal to 128/1024 = .125Mbps so yes a 1.5Mbs line would be approximately 12 times faster assuming they are both being used to capacity ! -- whether that speed would be realized depends on the data being sent\received for example if it is just small text files that require less than 128Kbs then you would not notice any speed difference.