Point codes are either 24 or 14 bits wide and have varying structure. The term structure refers to the grouping of bits within the full bit field and the meanings assigned to the groups.
The ITU point code is 14 bits wide. The ITU point code structure is not standardized throughout the world so Xygnada products rely on using a single decimal integer representation for ITU point codes. Here is a collection of ITU point code formats from around the world:
- UK
- decimal 14327 is structured as 13-15-55
- decimal 4457 is structured as 4-5-41
- There is not enough information in the example to derive the bit width of each of the 3 fields in the structured format.
- We do not know the meanings of the structured format fields.
- Moldova
- decimal 99 is structured as 1-35
- decimal 10 is structured as 0-10
- There is not enough information in the example to derive the bit width of each of the 2 fields in the structured format.
- We do not know the meanings of the structured format fields.
- Poland and Holland format is 3 decimal digit-3 decimal digit; for example
- PC = 5 - 137 - 5 is represented as 088-077 in the 3 decimal digit-3 decimal digit format, or as 11341 in decimal, or as 101 - 10001001 - 101 in binary, or as 2C4D in hex
- APC = 4 - 219 - 0 is represented as 077-088 in the 3 digit-3 digit format, or as 9944 in decimal, or as 100 - 11011011 - 000 in binary, or as 26D8 in hex
- These examples tells us there is also a 3 bit-8 bit-3 bit structure.
- We do not know the meanings of the structured format fields.
The 24 bit point code is used mainly in Canada, China, and the United States. In China, the ITU flavor of SS7 is used with a 24 bit point code. In Canada and the United States, the ANSI flavor of SS7 is used with a 24 bit point code. In the ANSI applications, the point code structure is three groups of 8 bits in the form of network-cluster-member. Each number is given in decimal format. We currently have no information on how the 24 bits are structured in China. Xygnada products use the three eight-bit field representation for 24 bit points codes, for example, 3 112 241. Note that the numbers 3, 112, and 241 are separated by spaces. In documentation, it is common to see the point fields separated by dashs like this, 3-112-241.