300-070 Question #367: Real Exam Question with Answer & Explanation

Question

Options

• A9.!
• B9!
• C9.*
• D9.XXXXXXXXXXX
• E9.1XXXXXXXXXX
• F9.[^9]XXXXXXXXXX

Explanation

The route pattern 9.1XXXXXXXXXX is the most specific match for the dialed string 9+13135551212, covering the outside access code, long-distance prefix 1, and a 10-digit NANP number.

Common mistakes.

• A. 9.! uses the variable-length ! wildcard that matches one or more digits, which would match this number, but CUCM's best-match algorithm selects 9.1XXXXXXXXXX first because it contains a literal digit 1 making it more specific.
• B. 9! omits the dot separator, meaning the entire dialed string including the 9 access code digit is forwarded to the destination unchanged rather than being stripped, which would cause incorrect call routing.
• C. In CUCM route patterns the asterisk () character represents the physical * key on the phone keypad and is not interpreted as a zero-or-more digit wildcard, so 9. would only match if the caller presses the * key after 9.
• D. 9.XXXXXXXXXXX uses 11 X wildcards that would technically match 9+13135551212, but because every position is a wildcard rather than a literal digit, it is less specific than 9.1XXXXXXXXXX and CUCM's match algorithm will not select it.
• F. 9.[^9]XXXXXXXXXX matches any non-9 digit followed by 10 digits after the separator, which would technically match this number since 1 is not 9, but the literal digit 1 in 9.1XXXXXXXXXX is more specific than the range expression [^9], so CUCM selects E instead.

Concept tested. CUCM route pattern wildcard matching and specificity rules

Reference. https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/admin/12_5_1/systemConfig/cucm_b_system-configuration-guide-1251/cucm_b_system-configuration-guide-1251_chapter_011.html

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