Overview

You would like to confirm whether you can use d0 as an identifier for the OrigAddressGSM parameter. You are also curious how to interpret d1 when there is no d0 reference. You have the encrypted characters for the OrigAddressGSM and you can decode them using 7-bit binary encoding. 

Information

Yes, you can consider TON alphanumeric represented by "d0" in the OrigAddressGSM field.

You can also consider the TON=4 and NPI=5 of origAddress to identify any application traffic originator.

Below are a couple of examples:

• d0 = alphanumeric/unknown
• d1 = alphanumeric/telephone

The first byte identifies the TON=alphanumeric while the second byte identifies the NPI used. See below other possible values for NPI but combinations of d0 (alpha/unknown) and d1 (alpha/telephone) are the most commonly used.

NumberingPlanIndicator ::= INTEGER

{ unknown (0), telephone (1), reserved (2), data (3), telex (4), scspecific5 (5), scspecific6 (6), reserved7 (7), national (8), private (9), ermes (10), reserved11 (11), reserved12 (12), reserved13 (13), reserved14 (14), reserved15 (15) }