During the days of 11.x and 12.0 IOS, i used to figure out the my service provider bandwith on a simple serial link by issuing the <sh controller ser x/y> command, and reading the clockrate figures. These days i am having it though with the 12.3+ versions. Any clue on the way out.
Attached is an example of the kind of output i recieve now. The point is that the link is slow and my manager needs to know what is happening.