Telecom Routing

One of the primary strategies in delivering cost effective
telecommunications services is known as Least Cost
Routing. This is the process where all possible routing
choices are evaluated based on their cost. The first or
optimum choice is considered to be the one with the
lowest associated cost.

Realistically there are other factors that need to be
considered. Other than cost the greatest consideration
is call quality. There may be several criteria that are
used to evaluate call quality. Among them are the ability
to complete the call, the fidelity of the speech signal
and the time needed to have the call answered.

The telecommunications industry has developed metrics
to measue and quantify the performance of their routing
decisions. Among them are the ASR (Answer Seizure
Ratio), ACD (Average Call Duration), and Call Setup Time
or PDD (Post Dial Delay). These indicate the probability
that the call will be answered, the length of time of the
average call, and how long it will take for the call to
receive a ringing signal from the called party.