Using a Period in SIP Dial Rule Patterns for Cisco 9971 IP Phones

D.

Asterisk (*) matches one or more characters.

The * gets processed as a wildcard character.

You can override this by preceding the * with a backward slash (\) escape sequence, which results in the sequence \*

The phone automatically strips the \, so it does not appear in the outgoing dial string.

When * is received as a dial digit, it gets matched by the wildcard characters * and period (.).

In SIP Dial Rule patterns, a period (.) is a wildcard character used to match any single digit from 0 to 9, the asterisk (*) or pound (#) symbols. When a SIP Dial Rule pattern is associated with a Cisco 9971 IP Phone that is registered to Cisco Unified Communications Manager, the period has a significant dialing impact as it allows for more flexible dialing patterns.

For example, if the SIP Dial Rule pattern is configured as 9.555XXXX, it will match any dialed string that starts with 9, followed by a single digit from 0 to 9, followed by the digits 555, and ending with any four digits (X represents any digit). This means that a user can dial any number that starts with 9, followed by the area code 555, and then any four digits.

Therefore, the correct answer is A. It matches any single digit from 0 to 9.