Cellular Network Infrastructure » Core Network (CN) » OsmoMSC

From 3GPP TS 129.002, section 17.7.8 "Common data types":

AddressString ::= OCTET STRING (SIZE (1..maxAddressLength))
-- This type is used to represent a number for addressing
-- purposes. It is composed of
--   a) one octet for nature of address, and numbering plan
--      indicator.
--   b) digits of an address encoded as TBCD-String.

-- a) The first octet includes a one bit extension indicator, a
--    3 bits nature of address indicator and a 4 bits numbering
--    plan indicator, encoded as follows:

-- bit 8: 1  (no extension)

-- bits 765: nature of address indicator
--   000  unknown
--   001  international number
--   010  national significant number
--   011  network specific number
--   100  subscriber number
--   101  reserved
--   110  abbreviated number
--   111  reserved for extension

-- bits 4321: numbering plan indicator
--   0000  unknown
--   0001  ISDN/Telephony Numbering Plan (Rec ITU-T E.164)
--   0010  spare
--   0011  data numbering plan (ITU-T Rec X.121)
--   0100  telex numbering plan (ITU-T Rec F.69)
--   0101  spare
--   0110  land mobile numbering plan (ITU-T Rec E.212)
--   0111  spare
--   1000  national numbering plan
--   1001  private numbering plan
--   1111  reserved for extension
--   all other values are reserved.

Here is an example of an alphanumeric address:

TP-Originating-Address - (Facebook)
   Length: 14 address digits
   1... .... = Extension: No extension
   .101 .... = Type of number: Alphanumeric (coded according to 3GPP TS 23.038 GSM 7-bit default alphabet) (5)
   .... 0000 = Numbering plan: Unknown (0)
   TP-OA Digits: Osmocom