Digit Mapping

You can use digit mapping to determine when the device stops collecting the digits of a dialed phone number from the Tel side (caller), after which it uses them for the destination number to establish the call. Digit mapping is typically used for closed numbering schemes.

The device stops collecting digits and starts sending the digits upon any of the following scenarios:

■ The maximum number of digits is received: You can configure the maximum number of collected digits that can be received from the Tel side. When the number of collected digits reaches this maximum (or a digit map pattern is matched before the maximum), the device stops collecting more digits and uses the collected digits for the called destination number. To configure the maximum number of collected digits, use the [MaxDigits parameter] parameter.
■ The inter-digit timeout expires (e.g., for open numbering schemes): The inter-digit timeout is the time that the device waits between each received (collected) digit. When the timeout expires, the device stops collecting more digits and uses the collected digits for the called destination number. To configure the timeout, use the [TimeBetweenDigits] parameter.
■ The phone's pound or number (#) key is pressed.
■ The digits match one of the digit map patterns: Digit map (pattern) rules are configured by the [DigitMapping] parameter. The digit map pattern can contain up to 52 options (rules), each separated by a vertical bar ("|"). The maximum length of the entire digit pattern is 152 characters. The digit mapping notations are described in the following table:

Digit Map Pattern Notations

Notation

Description

[n-m]

Range of numbers (e.g., "1-7").

.

(Single dot) Repeat digits until the next notation (e.g., T).

x

Any single digit.

Note: This notation doesn't apply to some scenarios when using the * or # key. For example, the key sequence of "**" must be presented in the dial plan as "*x.s" (instead of xx).

T

Dial timeout between received digits, which is configured by the [TimeBetweenDigits] parameter.

S

Short timeout between received digits, which is configured by the [TimeBetweenDigits] parameter whose value is then divided by 2. For example, if you leave the parameter at its default (i.e., 4), then the short timeout is 2 (i.e., 4 divided by 2). You can use the short timeout when you configure a specific rule after a more general rule. For example, if the digit map is "99|998", the device terminates digit collection when the first two 9 digits are received. Therefore, the second rule "998" can never be matched. But if you configure the digit map as "99S|998", then after the first two 9 digits are dialed, the device waits another two seconds, within which the caller can dial the digit 8.

Below is an example of a digit map containing eight rules:

DigitMapping = 11xS|00[1-7]xxx|8xxxxxxx|#xxxxxxx|*xx|91xxxxxxxxxx|9011x|9011x.T

In the example, the rule:

■ "00[1-7]xxx" denotes dialed numbers that begin with 00, and then any digit from 1 through 7, followed by three digits (of any number). Once the device receives these digits, it doesn't wait for additional digits, but starts sending the collected digits (dialed number) immediately.
■ "9011x.T" can apply to International numbers where 9 is for the dialing tone, 011 the country code, and then any number of digits for the local number.
● If you want the device to accept any number, make sure that the digit map contains the rule "xx.T"; otherwise, the device rejects all dialed numbers that can't be matched to any digit map.
● If you are using an external Dial Plan file for dialing plans (see Dialing Plans for Digit Collection), the device first attempts to locate a matching digit pattern in the Dial Plan file. Only if not found, does the device search for a matching digit pattern in the digit map.
● It may be useful to configure both Dial Plan file and digit maps. For example, the digit map can be used for complex digit patterns (which are not supported by the Dial Plan) and the Dial Plan can be used for long lists of relatively simple digit patterns. In addition, as timeout between digits is not supported by the Dial Plan, the digit map can be used to configure digit patterns that are shorter than those configured in the Dial Plan ( ([MaxDigits] parameter) or left at default. For example, the digit map "xx.T" uses the Dial Plan and if no matching digit pattern is found, the device waits for two more digits and then after a timeout ([TimeBetweenDigits] parameter), it sends the collected digits. Therefore, this ensures that calls are not rejected as a result of their digit pattern not been completed in the Dial Plan.