Mitel SX-200 Documentation page 540

3. ROUTING
3.01 The ARS feature is based upon the North American telephone
numbering system. Using the information reviewed in Part 2 of
this Section, one must consider trunking arrangements in the system.
Obviously there. must be a proper ratio of trunks to extensions. This
may be calculated by completing a traffic survey as per Section
3.02 These studies reveal trunk requirements within a system.
Trunks may be Foreign Exchange (FX), Wide Area Toll Service
(WATS), Standard CO trunks, Tie trunks, etc. The type and/or quantity
of each is determined during the traffic study. For example, in the case
of a customer who makes most of his calls to a specific distant area, a
number of FX trunks to that location's Central Office (CO) may be the
best and most economical method. The customer may wish to force
extension users to use FX trunks by Toll Control. This would work, but
under heavy traffic conditions many extensions would not be able to
complete calls due to busy FX trunks. It would be more economical
and efficient to steer the extension user to the most economical route
(i.e., WATS) available. The best method of routing (or steering) would
be one that did not require any special dialing (beyond an access
code) by an extension user. That is, the extension user would only dial
the ARS access code + the normal seven or 10 digits (the prefix may
be optional). The system would analyze the dialed digits and select a
route based upon the time of the day. The system would be pro-
grammed to insert and delete digits as required by the route selected.
The dialed number would be first stored, examined and a route se-
lected, then outpulsed rapidly (in a manner similar to speed call also,
during outpulsing the user would be connected to Music on Hold if
provided). The user would still retain full use of such features as Speed
Call and Multi-Digit Toll Control. In addition, if a trunk-busy (tone)
condition is encountered, the user may dial the Automatic Callback -
Busy code. The user would be called back when the first trunk in the
ARS routing is free. There are a maximum of 32 callbacks that may be
stored in the system. Upon answering the call, the user will be con-
nected to the trunk and the system will automatically outpulse the
digits (and prefix if required) dialed.
4. OPERATION
4.01 The primary goal in the operation of ARS is to provide the most
economical trunk to a user at a given hour of the day. At the
same time, the ARS feature must retain a degree of simplicity that
requires the user to dial only the ARS feature code, then normal digits
(Figure 4-l).
4.02 As described in Part 2 of this Section, there may be seven or 10
digits dialed with a "1' prefix In the case of Interchangeable
Office codes, the system may be alerted to the NM difficulty by
selecting System Option 242 (ARS Unrestricted Office Locale Enable).
This option will alert the system to look for a '1" after the ARS access
code, for all long-distance calls outside of the Home Area code. In this
case, an extension that does not dial "1" after the ARS code will
SECTION MITL9105/911 o-096-21 3-NA
Page 3