Call-By-Call Min/Max Control - Toshiba DK14 Programming Manual

ISDN
Call-By-Call Overview

Call-by-Call Min/Max Control

There are two variables that can be programmed for each trunk group to ensure optimum call
utilization. These are the minimum and maximum values.
o The minimum (min.) value is defined as the minimum number of B-channels in reserve that
are necessary to ensure that a given trunk group can adequately service calls. The default value
is zero.
o The maximum (max.) value is the maximum number of B-channels that are necessary to
ensure that a given trunk group can adequately service calls during a peak period. The default
value is 23.
The min and max values must be determined by you based on the traffic volume and environment.
Here are some guidelines:
o The total number of lines assigned to all trunk groups as minimums should not exceed the
number of B-channels in the channel group. For example, if there are 23 B-channels in the
channel group, the total sum value programmed as minimum in all trunk groups should not
exceed 23.
o The maximum value typically never exceeds the total of the subscribed B-channels for the
channel group. The programmed maximum value is typically used to limit the total number of
shared lines available to a given trunk group.
Example 2
This example shows how to determine the maximum number available to a trunk group.
Refer to
the number of B channels in the channel group. The remainder is the total number of lines
available for that trunk group. This is outlined in steps 1 and 2 below.
1. Determine the total number of lines
available to Trunk Group 1.
3
+ 5
8
2. Subtract from other Trunk Groups'
min. values from the number of
B-channels in that Channel Group.
23
- 8
15
Note
Maximum trunk group values are set in Program * 67-4. Minimum trunk group values (reserved)
are set in Program * 67-3.
7-12
Figure 7-3. Add the min. values from the other trunk groups, then subtract that sum from
Trunk Group 2 Min.
Trunk Group 3 Min.
Min. Value for Trunk Groups 2 & 3
B-channels in Channel Group 1
Min. Value for Trunk Groups 2 & 3
Lines available to Trunk Group 1
(8 reserved + 7 shared)
Even through the max. value is
set for 23 channels, only 15
channels are available for
Trunk Group 1.
Channel Group 1
Trunk Group 1
Max. = 23
Min. = 8
Trunk Group 2
Max. = 7
Min. = 3
Figure 7-3 Example 2 – Shared Trunk Lines
Strata DK Programming
Trunk Group 3
Max. = 12
Min. = 5
4917
5/00