AudioCodes Mediant 4000 SBC User Manual page 275

CHAPTER 16 Services
In addition to Cost Groups, the device can calculate the call cost using an optional, user-defined
average call duration value. The logic in using this option is that a Cost Group may be cheap if the
call duration is short, but due to its high minute cost, may prove very expensive if the duration is
lengthy. Thus, together with Cost Groups, the device can use this option to determine least cost
routing. The device calculates the Cost Group call cost as follows:
Total Call Cost = Connection Cost + (Minute Cost * Average Call Duration)
The below table shows an example of call cost when taking into consideration call duration. This
example shows four defined Cost Groups and the total call cost if the average call duration is 10
minutes:
Table 16-15:Call Cost Comparison between Cost Groups for different Call Durations
Cost Group
A
B
C
D
If four matching routing rules are located in the routing table and each one is assigned a different
Cost Group as listed in the table above, then the rule assigned Cost Group "D" is selected. Note
that for one minute, Cost Groups "A" and "D" are identical, but due to the average call duration,
Cost Group "D" is cheaper. Therefore, average call duration is an important factor in determining
the cheapest routing role.
Below are a few examples of how you can implement LCR:
■ Example 1: This example uses two different Cost Groups for routing local calls and
international calls:
Two Cost Groups are configured as shown below:
1. "Local Calls"
2. "International Calls"
The Cost Groups are assigned to routing rules for local and international calls:
Routing Index
1
2
■ Example 2: This example shows how the device determines the cheapest routing rule in the
Tel-to-IP Routing table:
The 'Default Call Cost' parameter in the Routing Policy rule is configured to Lowest Cost,
meaning that if the device locates other matching routing rules (with Cost Groups assigned),
the routing rule without a Cost Group is considered the lowest cost route.
● The following Cost Groups are configured:
Connection Cost Minute Cost
1
0
0.3
6
Cost Group
Dest Phone Prefix
2000
00
Total Call Cost per Duration
1 Minute
6 7
10 10
8 8.3
1 7
Connection Cost
2
6
Destination IP
x.x.x.x
x.x.x.x
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Mediant 4000 SBC | User's Manual
10 Minutes
61
100
80.3
16
Minute Cost
1
3
Cost Group ID
1 "Local Calls"
2 "International Calls"