Setting Voicemail Waiting Indication via SMS

This entry is part 16 of 17 in the series Sending out an SMS

As shown in an earlier post, the Data Coding Scheme (DCS) octet in the SMS PDU can be used to turn a regular text message into a flash message.

Another feature of SMS that is enabled through use of the DCS is the Message Waiting Indication:

  • When someone leaves you a voicemail, the voicemail system communicates with the SMSC to send your phone a special SMS message that turns on the little icon on your phone that indicates that you have a new voicemail.
  • When you listen to your voicemail, the voicemail system also communicates with the SMSC to send your phone a SMS message that turns the little icon off again.

Using the DCS you can turn the voicemail icon on or off yourself.

This is an example PDU to set a voicemail indication:


Here is what the individual octets represent:

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