Introduction 95
SmartLink 4020 Getting Started Guide C • Dial plans
Introduction
The MGCP and SIP code will allow provisioning (via web browser) of the dial plan. A dial plan gives the unit
a map to determine when a complete number has been entered and should be passed to the SIP server or gate-
keeper for resolution into a destination IP address. Dial plans are expressed using the same syntax as used by
MGCP NCS specification.
The formal syntax of the dial plan is described by the following notation:
Digit ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
Timer ::= "T" | "t"
Letter ::= Digit | Timer | "#" | "*" | "A" | "a" | "B" | "b" | "C" | "c"| "D" | "d"
Range ::= "X" | "x" -- matches any digit
| "[" Letters "]" -- matches any of the specified letters
Letters::= Subrange | Subrange Letters
Subrange::= Letter -- matches the specified letter
| Digit "-" Digit -- matches any digit between first and last
Position::= Letter | Range
StringElement::= Position -- matches any occurrence of the position
| Position "." -- matches an arbitrary number of occurrences
including 0
String ::= StringElement | StringElement String
StringList::= String | String "|" StringList
DialPlan::= String | "(" StringList ")"
A dial plan, according to this syntax, is defined either by a (case insensitive) string or by a list of strings. Regard-
less of the above syntax a timer is only allowed if it appears in the last position in a string (12T3 is not valid).
Each string is an alternate numbering scheme. The unit will process the dial plan by comparing the current dial
string against the dial plan, if the result is under qualified (partial matches at least one entry) then it will do
nothing further. If the result matches or is over-qualified (no further digits could possibly produce a match)
then send the string to the gatekeeper and clear the dial string. The Timer T is activated when it is all that is
required to produce a match. The period of timer T is 4 seconds. For example a dial plan of (xxxT|xxxxx) will
match immediately if 5 digits are entered, it will also match after a 4 second pause when 3 digits are entered.
Sample Dial Plans
Simple Dial Plan
Allows dialing of 7-digit numbers (e.g. 5551234) or an operator on 0. Dial plan is (0T|xxxxxxx)
Non-dialed Line Dial Plan
As soon as handset is lifted the unit contacts the gatekeeper (used for systems where DTMF detection is done
in-call). Dial plan is (x.) i.e. match against 0 (or more) digits. Note: the dot ‘.’
Complex Dial Plan
• Local operator on 0, long distance operator on 00
• 4-digit local extension number starting with 3, 4, or 5
• 7-digit local numbers are prefixed by an 8