3Com CoreBuilder 7000 Operation Manual page 119

Figure 40 Switch Cell Rate Utilization for VBR and CBR Service Classes
GCAC for ABR Service Class
The GCAC for the ABR service is similar to that of the VBR service except
that it is based on the minimum cell rate (MCR) parameter read from the
traffic contract.
Figure 41 shows the cell rate utilization for the entire CoreBuilder 7000
switch for the ABR Service Class.
Available Cell Rate
Figure 41 Switch Cell Rate Utilization for ABR Service Class
GCAC for UBR Service Class
A connection with a unspecified bit rate (UBR) service is never rejected
because of bandwidth considerations. However, the selective cell discard
may be used on a UBR connection to limit its influence on connections of
other service classes.
Displaying CAC Parameters
You can display the CAC parameters which are used at a port (see "Call
Admission Control" on page 219 in the Management Guide).
Displaying Call Contract Parameters
You can display the traffic contract parameters which are used for a call
(see "Display Call Routed to ATM Address" on page 165 in the
Management Guide).
Call Admission Control
Maximum Usable Cell Rate
Aggregate Minimum Rate =
Actual Allocated Capacity
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