Flash SMS support in SMPP SMS Services
The FLASH SMS functionality is implemented in Ozeki NG SMS Gateway. If you use the SMPP protocol, you have to configure your SMPP service provider connection to support FLASH SMS messages.
Configure your SMPP service provider connection
You can use FLASH SMS in SMPP connections in two ways:
1.) The first option: If your SMPP provider does not support TLV fields, you can encode the FLASH SMS message class setting in the DCS field of the SMPP PDU. To use this option, make sure the "Put UDH into TLV for text SMS" checkbox is not checked in Message data tab of the SMPP service provider connection form. On the same tab set the "Server charset:" to "Default"! After this is configured, you can send GSM 7-bit charset messages as flash SMS.
Please note, that if you use UNICODE characters in SMPP 3.3 or SMPP 3.4 the only way you can use FLASH SMS is if your provider supports the TLV fields.
2.) The second option: If your SMPP provider supports TLV fields, here is what you should do: Make sure the "Put UDH into TLV for text SMS" checkbox is checked. If TLVs are supported by your service provider, both GSM 7bit and UCS2 messages can be sent as FLASH.
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