WorstCase Traffic Utilization
The default analysis is to identify up to 10 failures for the worstcase utilization on each interface in the network.
Worst case is the highest utilization that a particular interface experiences over all the failure sets and traffic levels that you selected. WAE Design also determines which combination of failures would cause this worstcase utilization.
Alternatively, you can record failures causing utilizations within a specified percent of the worstcase utilization.
Note 
To control the number of threads that WAE Design processes in parallel when examining failure scenarios, set the “Maximum number of threads” field. 
Upon finishing the analysis, WAE Design switches to the WorstCase Traffic view and updates the plot to simultaneously display all worstcase failures (Figure 1). It also updates the following columns in the Interfaces and Circuits tables.

WC Util—The worstcase utilization for that interface. The worstcase for a circuit is defined to be whichever of the worst cases of the two constituent interfaces results in the larger utilization. Thus, for circuits, this value is the larger of the WC Util values for the two interfaces in the circuit.

WC Traffic—The actual traffic (Mbps) through the interface under the worstcase scenario.

WC Traff Level—The traffic level under which this worstcase scenario occurs.

WC Failure—List of one or more failures that cause the worstcase failure of the circuit. An easier way to read this list is to rightclick an interface and choose Fail to WC.
Example: The circuit between cr1.lon to cr1.par, the cr1.lon node, and the L1 link between lon and par would all cause the worstcase utilization failure. ct{cr1.lonto_cr1.par}cr1.par{to_cr1.lon}}; nd{cr1.lon};L1lnk{lonparlonpar}
If you record failures causing utilizations within a given percent of worst case, this column shows QoS violations as a percent. (See WorstCase QoS Violations.) If the number is positive, then the allotted capacity has been surpassed. If negative, the capacity has not been surpassed. For example, if a circuit has 10,000 Mbps capacity, and if the amount of traffic on it as a result of three different failures is 11,000, 8000, and 4000 Mbps, the utilizations are 10%, –20%, and –60%, respectively and in descending order.
Example: The circuit between cr1.ams and cr2.lon is the worstcase failure and would cause this interface to exceed its capacity by 24.75%. The failure of the cr2.lon node would cause the interface traffic to go to its second highest utilization, which is 2.8% less than its capacity.
ct{cr1.ams{to_cr2.lon}cr2.lon{to_cr1.ams}} (–24.75%);nd{cr2.lon} (2.8%)
For information on reading notation of objects within tables, see the Cisco WAE Design Integration and Development Guide .

WC Service Class—The service class for which this worstcase scenario occurs. For information on running a Simulation Analysis with QoS, see WorstCase QoS Violations.
Note
For information on worstcase calculations for VPNs, see VPN Simualtion.
WorstCase QoS Violations
WAE Design includes QoS bound (maximum available capacity) as part of the worstcase calculations. If there are no QoS parameters set, then the QoS bound is 100% and violations occur if utilization goes over that 100%. However, if a worstcase policy has been set on a service class or if interface queue parameters have been set, then worstcase QoS violations are calculated. In these instances, WAE Design identifies the interface with the highest percentage of QoS violation as the worstcase possibility. The following columns are updated accordingly.

WC QoS Bound—The worstcase interface capacity available without violating these QoS requirements. This value is based on available capacity, traffic utilization, worstcase policies set on service classes, and interface queue parameters. The WC QoS Bound (%) column identifies this same value as a percentage of the total capacity.

WC QoS Violation—The worstcase traffic minus the worstcase capacity permitted (worstcase QoS bound). A violation occurs if the QoS capacity allotted through worstcase policies for service classes is exceeded or if QoS capacity allotted through interface queue parameters was exceeded. If the number appearing in the WC QoS Violation column is positive, then the allotted capacity has been surpassed. If negative, the capacity has not been surpassed. The WC QoS Violation (%) column identifies this same value as a percentage of total capacity.
To see the cause of worstcase QoS violations, rightclick a circuit and choose Fail to WC. The table that appears lists all causes of this interface’s worstcase utilization and its worstcase QoS violations. Choose the worstcase failure to view, and click OK.

WC Service Class—The service contributing to the worsecase QoS violation.
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Worstcase QoS calculations for VPNs 
Failing Circuits to WorstCase Utilization
You have the option to selectively view each failure scenario that causes the worstcase utilization or worstcase QoS violation for a single interface.

Rightclick an interface or a circuit and choose Fail to WC. If there is only one worstcase failure (listed in the WC Failure column), the object causing the worstcase utilization is listed. You can select it to fail it immediately.
If there are multiple possibilities for a worstcase failure, or if there is a range of failures within a percentage of the worstcase failure, a WorstCase Failures dialog box lists each failure, its worstcase utilization percent, and its QoS violation percent (Figure 1). Choose the worstcase failure to view, and click OK. The network plot changes to show this particular failure scenario. If you choose to fail an L1 link or L1 node, switch to the L1 view to see the failure.
Note
If you choose an interface, you are actually failing its associated circuit to its worst case.

Alternatively, to filter to these worstcase failures for an interface without invoking a failure, rightclick an interface or a circuit, choose Filter to > Filter to WC, and then choose the worstcase failure scenario of interest. If you fail this object from here, it achieves the same as if you had selected it from the WorstCase Failures dialog box.