Percentage Distribution Algorithm

A node with a percentage distribution mode distributes passes through the node in a specified proportion.

The percentage distribution calculation occurs each time a call passes through the distribution algorithm and it is based on the number of calls that have passed though the node since it was configured.

Initially flow is passed to each configured percentage item in order of decreasing percentage value.

Subsequent passes are allocated according to the configured percentages.

For example, having 4 configured percentage items of 15%, 20%, 30% and 35%, after 16 passes the platform would have the following table stored for the Node:-

Configured Percentage	Pass Count	Current Percentage	Weight
15	2	12.5	-2.5
30	5	31.25	1.25
20	3	18.75	-1.25
35	6	37.5	2.5

The “Pass Count” column represents the number of times the flow has passed through that percentage item since the node was configured.

The “Weight” column calculation is the “Current Percentage” minus the “Configured Percentage”

Each time a call is presented to the distribution algorithm, it uses the table above to select the percentage item with the lowest value in the “Weight” column then increments the “Pass Count” for that item. In the example above the next pass would select the 15% item increasing the Pass Count from 2 to 3 resulting in the following table:-

Configured Percentage	Pass Count	Current Percentage	Weight
15	3	17.64705882	2.647059
30	5	29.41176471	-0.58824
20	3	17.64705882	-2.35294
35	6	35.29411765	0.294118

The next pass would select the 20% item as this now has the lowest value in the “Weight” column. The table would then be updated as follows:-

Configured Percentage	Pass Count	Current Percentage	Weight
15	3	16.66666667	1.666667
30	5	27.77777778	-2.22222
20	4	22.22222222	2.222222
35	6	33.33333333	-1.66667

The next pass would then select the 30% and so on….. In the event of two or more percentage items having the same “Weight” value, the item with the highest configured percentage is selected.

Scope

Global

The Pass Count represents all inbound calls that have passed through the Node since it was last configured. The Pass Count is reset to zero when the percentage configuration is changed. This option should be used when you want to apply percentage distribution to all inbound calls to a service.

Call

The Pass Count is reset to zero for each inbound call that passes through the Node. The percentage calculation is isolated to an individual inbound call.