Table of Contents

Screen

The block Screen matches the incoming caller-ID against a list of number patterns, then branches on the result. If the caller-ID contains a number pattern which is in the list provided, then the regular success output on the right is taken, otherwise the call takes the failure output on the bottom of the block. Anonymous calls are sent to failure output by default, but can be accepted by setting the Screen Anonymous parameter.

Settings for this block

  • Label: An arbitrary label to help identify the block.
  • Allow Numbers: A comma-separated list of numbers. Patterns can also be used where '?' matches a digit. Digits '0-9' and '?' with ',' separation allowed (no spaces).
  • Allow Anonymous: Check this box to send calls with no caller-id to the success output.

Examples for 'Allow Numbers' and Pattern Matching

Note that caller-id is passed from other networks, we try to standardise to the full international number with a leading plus (example: +35386123123123) but this is not guaranteed.

  • 123456789 - This would allow any call which contains 12345689 anywhere in the caller-id. For example 0123456789 or +44123456789 or 0044123456789.
  • 123456111,123456222 - This would allow any call which contains 123456111 or 123456222 anywhere in the caller-id. For example 0123456111 or +44123456222 or 0044123456111 or 0044123456222.
  • 111,222 - This would allow any call which contains 111 or 222 anywhere in the caller-id. For example 0123456111 or +44123456222 or 0044111234561 or 0044123222123.
  • 0 - This would allow any call which contains zero anywhere in the caller-id. For example 023343232332 or 003312334343 or +44232344545454.
  • 00 - This would allow any call which contains '00' anywhere in the caller-id. For example 023343230032 or 003312334343.
  • 00??? - This would allow any call which contains '00' followed by 3 digits anywhere in the caller-id. For example 023343200323 or 003312334343 (023343240033 would NOT be allowed).
  • 00??3 - This would allow any call which contains '00' followed by 2 digits then 3 anywhere in the caller-id. For example 023343200323 or 003332334343 (023343200331 would NOT be allowed).
  • ???????????? - This would allow any calls which have a minimum 12 digits as caller-id, note that ? matches letters too and if the call was 'unknown' it would match and allow it.
  • ?207???????, ?203???????, ?208??????? - This would match calls from UK London example 02071234567 or 00442071234567 or +442071234567.

See an Example using Screen