This attribute specifies the committed burst size (Bc). It represents
the amount of data that a network agrees to transfer under normal
conditions over a measurement interval when rate enforcement is in
effect. Data marked DE=1 is not accounted for in the committed
burst size.
When rate enforcement is not in effect, this attribute is ignored.
Note: The committedInformationRate must have a value of 0 when
rate enforcement is in effect and committedBurstSize has a value of
0.