As per the SMPP protocol, On SMPP:submit_sm the UDHI (User Data Header Indicator) in the esm_class parameter :
esm_class = 0x40 x1xxxxxx is set in the esm_class field to indicate udhi is true
The concatenation UDH values are inserted at the start of the message body.
For example
- Message 1 (UDH+153 chars length message):
- esm_class = 0x40 x1xxxxxx
- short_message = 0x05 0x00 0x03 0x05 0x02 0x01Barcelona are to appeal against Uefa’s proposal to ban Andres Iniesta for an additional Champions League match for allegedly provoking a yellow card.The
- Message 2 (UDH+rest of the message):
- esm_class = 0x40 x1xxxxxx
- short_message =0x05 0x00 0x03 0x05 0x02 0x02 26-year-old Spain midfielder was booked in the quarter-final against Shakhtar Donetsk, meaning he missed the return leg but would then be available.
- Concatenation UDH structure:
Remark: The maximum number of characters per concatenated message depends on the encoding:
- 153 characters for 7-bit encoding (e.g. Latin-1/9 and GSM8)
- 134 characters for 8-bit encoding (Binary)
- 67 characters for 16-bit encoding (Unicode)
ITPRO CHARACTER COUNT POLICY FOR PLAIN TEXT MESSAGE:
0-160 = 1 standard SMS message
161-306 = 2 concatenated SMS messages
307-459 = 3 concatenated SMS messages
460-612 = 4 concatenated SMS messages
613-765 = 5 concatenated SMS messages
766-918 = 6 concatenated SMS messages
919-1071 = 7 concatenated SMS messages
1072-1224 = 8 concatenated SMS messages
ITPRO CHARACTER COUNT POLICY FOR UNICODE MESSAGE:
0-70= 1 standard SMS message
71-134 = 2 concatenated SMS messages
135-201= 3 concatenated SMS messages
202-268 = 4 concatenated SMS messages
269-335 = 5 concatenated SMS messages
336-402 = 6 concatenated SMS messages
403-469 = 7 concatenated SMS messages
470-536 = 8 concatenated SMS messages