Administrator's Guide

Features and technical reference
555-233-5061490 Issue 5 October 2002
Automatic circuit assurance
Automatic circuit assurance (ACA) helps you identify possible trunk
malfunctions. With ACA enabled, the system measures the holding time of each
trunk call. If the measurements show calls with either extremely long or extremely
short holding times, MultiVantage places a referral call to an attendant or
telephone.
The system records holding time from when a trunk is accessed to when it is
released. You set short-holding-time and long-holding-time limits for each trunk
group. The system then compares the recorded holding times against these limits.
You enable ACA for the entire system, and administer thresholds for individual
trunk groups. You can have all trunks or only certain trunks measured.
MultiVantage deals with long-holding and short-holding calls differently. For
every call that is shorter than the administered short-holding time, the system
increases the short-holding counter by 1. For calls over the same trunk that are
within the normal range, it decreases the short-holding counter by 1. Thus, trunks
that handle a normal variety of call lengths are not singled out as faulty. If the
counter reaches the administered short-holding threshold, the system places a
referral call.
If one long call exceeds the long-holding time, the system makes a referral call.
You cannot measure personal CO lines, out-of-service trunks, or trunks
undergoing maintenance testing.
The referral call
The display or voice-synthesized message that accompanies an ACA call contains
the following information:
■ The fact that this is an ACA call
■ The trunk access code, trunk group number, and trunk group member
number
■ The type of referral (short or long holding time)
Once the referral call is answered, this information is displayed and remains
displayed until the call is released. If the call is not answered within three minutes,
the call stops. The system places the call again after one hour, and continues to
place the call hourly until someone answers.
The attendant or telephone user who receives the referral call can stop further calls
by pressing the aca-halt button, if one is provided. This is a toggle button, and
turns off the feature until the user presses the button again.