10 appendix d: dial plans, Teledex ip250d user’s guide sip/mgcp – Teledex IP250DVoIP User Manual

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Teledex IP250D User’s Guide SIP/MGCP

APPENDICES

24

10 Appendix D: Dial Plans

The IP Phone 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 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. 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 overqualified (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 four (4) seconds. For example, a dial plan of

(xxxT|xxxxx)

will match

immediately if five (5) digits are entered, it will also match after a four (4) second pause
when three (3) digits are entered.

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