Dialing rules are required to standardize the format of a group of users attempting to make the same type of calls, e.g. internal extension dialing. As not all users dial in the same way, the dial plan, which is defined at the firm level, manipulates the digit strings to standardize various formats to get the digits formatted in a way that will be acceptable for the call processing.
Simple Dial Plan:We have two basic levers that can be used to do basic digit standardization:
- Digit Prefix: This field will add to the beginning of all digit strings a set of characters
- Example: +91
- Extension Length: As not all calls need to have the digit prefix added, customers can specify a digit length that would exclude the digit prefix from being added to the beginning of the string
Cloud9 also supports customers creating a more complex dial plan. Creating a complex dial plan is based on pairs of patterns and actions.
Complex Dial Plan:
- Patterns: String of digits that the dial plan will look to match in order to take action on
- Actions: Once a pattern match has occurred determine what action should be taken
Acceptable Inputs to Create Patterns:
- Numbers: Any numbers 0 to 9 will be treated literally
- Special Characters: Star (*), Pound (#), and Plus (+) will all be treated literally
- Any Digit: X should be used to denote any interchangeable digit
- Any Character: x should be used to denote any interchangeable digit or special character listed above
- Consecutive Digit Range: [ -] should be used to express a consecutive digit range such [4-7]11 would convey 411, 511, 611, and 711
Acceptable Actions to be Taken on Digit String:
- Remove one digit from the beginning of the digit string: r
- Remove one digit from the end of the digit string: R
- Insert one digit at the beginning of the digit string: i
- Insert one digit at the end of the digit string: I
If multiple digits need to be inserted or removed, then simply string together multiple actions.
Some Examples of Pattern, Action Pairs:
- Example: +912125551234 would be sent as 51234
- Potential extension dialing
- Example: 12125551234 would be sent as +912125551234
- External dialing
The dial plan is not required to take action on all patterns, if there is no pattern to match in the dial plan then the digits will be sent as they are entered to the call control platform. It will then be the responsibility of the call control platform to send back a 404 if the digit string is invalid.