Overview

A third-party application is having issues when trying to send messages with the MSISDN as the message title and the messages are getting blocked by the SMSC. 

Solution

This issue may be caused by a faulty data coding configuration.

Diagnosing the issue

To confirm that this is the root cause, run the following command on your traffic nodes to generate a trace file: 

tcpdump -i any port 9500 -s0 -w /var/tmp/`hostname`_Test.pcap

Then, open the pcap file that is generated using software such as Wireshark. Use the search term "Data coding" to search for the data coding details: 

In the search results, check the configured Data Coding Scheme (DCS):

Based on the SMPP Protocol Implementation Compliance Statement document, value 0xf0 is not supported on the AO-MT routing path:

For AO-AO all values of data_coding are supported. For AO-MT or AO-Store to GSM handsets, values 0, 4, and 8 are supported.

For reference, a correctly configured DCS will look like the following: 

Changing the DCS settings

To fix this issue, you will have to change the byte value of the DCS settings in the AO rule. To do so:

1. In the MGR GUI, navigate to Routing > Routing Rules > AOR
   
   
   
   
2.  Select the Application/AOR that is having issues. Scroll down to the field DCS [cond] and from the dropdown menu, select Byte Value (00-FF). A text box will appear to the right, in this enter the value 00. 
   
   
   
   
3. Scroll down and click on Save: