The traffic reports shown below represent a series of Apogee Trunk Utilization and Traffic Analysis
reports taken quarterly at an organization experiencing considerable call volume growth during the
time period under study (click to view).

As indicated on the Trunk Utilization report, incoming calls hunt from the bottom of the trunk
group (route) upward and the outgoing calls hunt from the top of the group downward.  It
is clear in the initial quarter on the Trunk Utilization (report on the left in the foreground)
that there is plenty of call handling capacity and that fact is also verified in the Erlang
calculations tabulated in the corresponding Traffic Analysis report (report on the right in
the foreground).



Note on successive Trunk Utilizations reports that the incoming and
outgoing traffic visually start to "bang" into each other.  In the fourth quarter
Trunk Utilization report there might still seem to be sufficient traffic handling capacity as the
highest percent utilization on any trunk is about twenty four (24) percent.  The Traffic
Analysis report for that quarter, however, indicates otherwise - from 2:00 PM to 2:59 PM
approximately ninety two (92) percent of the time all trunks in the group were busy.  More
trunks are required for a P.01 grade of service than exist in the group - blocked calls begin to
appear.



The different conclusions that might be derived from the two reports can be attributed to the
Poisson statistics that describe how calls tend to clump together.  This difference also
illustrates why Apogee traffic reports are so powerful and how simple summary reports can be
misleading.



Furthermore, in multi-site systems with PBX equipment networked in tandem, it is absolutely
essential that ALL members involved in trunk-to-trunk routing be assigned the proper usage
statistics to obtain proper traffic analysis calculations in a manner similar to the approach
used in Apogee.  Too often only the primary trunk statistics are tallied and not the
secondary.



Proper analysis of multi-site systems in tandem PBX configuration also often
requires extensive Call Translation to present the call data in the straightforward
fashion achieved by Apogee.