LevelOne 4100 User Manual

Appendix A. Dial Plans

The 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 gatekeeper for resolution into an 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 in 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. Regardless 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 it sends the string to the gatekeeper and clear the dial

string. The Timer T is activated when it has 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.