An advance over the prior art is achieved through an efficient method for
an admission control algorithm and a scheduling mechanism that complement
each other in providing the following three classes of service. A first
class of service is termed Class 1 where users specify a nominal amount
of bandwidth desired. A second, lower tier service class is termed Class
2, wherein users specify a nominal and minimum amount of bandwidth
desired when entering into a network connection. A third server class is
Class 3, where Class 3 users are treated as best effort users. For Class
1 users the methodology of the present invention provides a guaranteed
nominal amount of bandwidth. The admission control procedure ensures that
Class 1 users are admitted only if resources exist to satisfy the nominal
bandwidth requirements of the Class 1 users. Class 2 users are admitted
if resources exist to satisfy the minimum bandwidth requirements of the
user. Class 2 users are served with a bandwidth of up to their nominal
bandwidths if there is capacity left after serving the Class 1 users with
their nominal capacities. Class 3 users are served only if the Class 2
users have received their nominal bandwidths.