1. DSR TIF User's Guide
  2. TIF Features
  3. TIF Blocklist Features
  4. TIF Selective Screening Feature
  5. TIF Selective Screening Call Types

2.6.5.1 TIF Selective Screening Call Types

The TIF Selective Screening process is based on Call Types configured for a DN in the Number Portability. The Call Types of a DN are a list of numerical values in the range of 1-254, 255 , and 0. The zero (0) value indicates that the specific Call Type is not provisioned. The 255 value (hexadecimal 0xFF) of the first Call Type, which is the first byte of the digit string, indicates a wild card (any/*). Only the first number in the set of eight numbers can be provisioned with this wild card value of 255 (any/*) because the following seven numbers will be ignored. Any other Call Type except the first Call Type provisioned as 255 (0xFF/any/*) will be treated as not provisioned.

The Call Types for a DN are stored in the Number Substitution DN field. The Number Substitution DN field for the DN is stored in the Number Portability. The Number Substitution DN field is a 15-digit digit string, with two digits stored per byte for a total of eight bytes). This allows provisioning seven 1-byte Call Types and one 4-bit Call Type for a total of eight possible Call Types per DN. The first seven Call Types a range from 1 till 254, and the eighth Call Type can have a value between 1 and 15. The Call Types are provisioned as hexadecimal digits: the first 7 Call Types are one-byte-long Call Types - as a pair of hexadecimal digits, and the last - eighth Call Type - as a single hexadecimal digit.

The Call Type for CdPN can also be configured with NPP rules for TIF NPP Service. The SELSCR Service Action is associatd with the configurable SAxDGTS parameter. A single Call Type (0x0 - 0xFF) can be configured in the SAxDGTS field corresponding to the SELSCR Service Action in the NPP Action Set.

The Call Types configured in the SAxDGTS parameter take precedence over the Call Types configured in the Number Substitution DN field. If the Call Type for the CdPN is configured in the SAxDGTS field, then the Call Types configured in the Number Portability are not considered for the CdPN. The Call Types for CgPN are always fetched from Number Portability.

Only the first Call Type configured for the CdPN in Number Portability is considered for Selective Screening. If more than one Call Type is configured for the CdPN in Number Portability, then the rest of the Call Types after the first Call Type are ignored.