A network engineer designs a new dial plan and wants to block a certain range of numbers (8135100 through 8135105)
What is the most specific route pattern that can be configured to block only the numbers in this range?
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A. B. C. D.A.
The most specific route pattern that can be configured to block only the numbers in the range of 8135100 through 8135105 is option A, which is 813510[012345].
Explanation:
In a dial plan, a route pattern is used to match the dialed digits with the destination number or route. Route patterns are created using regular expressions or wildcards. Regular expressions use special characters to match patterns of text. Wildcards are characters that represent one or more digits.
In option A, the route pattern 813510[012345] matches any number that starts with 813510 and ends with a digit between 0 and 5. The square brackets [] indicate a character set, which means that any digit within the set can be matched. The pattern will match the numbers 8135100, 8135101, 8135102, 8135103, 8135104, and 8135105. Any other number that starts with 813510 will not match this pattern and will be allowed through the dial plan.
Option B, 813510[12345], is not as specific as option A because it will match any number that starts with 813510 and ends with a digit between 1 and 5. This includes the numbers 8135101, 8135102, 8135103, 8135104, and any other number that ends with 1, 2, 3, 4, or 5.
Option C, 813510[^0-5], uses the caret (^) character to indicate a negated character set. This means that any digit except 0-5 can be matched. This pattern will match any number that starts with 813510 and ends with a digit other than 0-5. It will block more numbers than just the range of 8135100-8135105.
Option D, 81XXXXX, is a wildcard pattern that matches any number that starts with 81 and has six digits. This pattern will block all numbers that start with 813510, as well as other numbers that start with 81. It is not specific enough to block only the range of 8135100-8135105.