Instruction manual

Page 1243 of 3156
Features and Services
Dial Tone Detection
Contents
The following are the topics in this section:
Feature description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1243
Operating parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244
Feature interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244
Feature packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244
Feature implementation . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244
Task summary list . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244
Feature operation . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1245
Feature description
The Dial Tone Detection (DTD) feature is needed because the first digit
cannot be sent until the dial tone is detected on calls to a Public Switched
Telephone Network (PSTN). This avoids the outpulsing of digits before the
PSTN is ready to accept them, thus avoiding either the loss of digits or the
misrouting of calls. The possibility of circumventing code dialing restrictions
is also minimized by the feature.
The feature is configurable on a route basis for all types of routes.
The time-out for the route is statistically averaged over the last eight times
that Dial Tone Detection was involved. Either the running-average time or the
pre-overlay programmed minimum time is used as the trunk time out,
whichever is greater. Dial Tone Detection can be invoked every time an
outgoing trunk route is selected, regardless of the selected feature.