This means SMS Central has successfully delivered the message to the carrier.
The message failed to reach the handset. It can be due to a hard bounce (the number is wrong or disconnected) or a soft bounce (the handset is out of coverage).
The message is still in SMS Central’s queue getting ready to be delivered.
We are still waiting for a Delivered/Bounced notification from the carrier. In most cases, the message will have been delivered.
You create a campaign and send 100 SMS.
Queued + Delivered + Bounced = 100 SMS
Usually the number of SMS Queued will go down as the messages leave SMS Central's gateway, and the number of blanks will be updated with delivered/bounced.
So, as soon as you send the campaign you will find:
Queued (100) + Delivered (0) + Bounced (0) = 100 SMS
As the campaign progresses, the queued number will go down and the delivered/Bounced will go up:
Queued (20) + Delivered (70) + Bounced (10) = 100 SMS
Once the messages are out of SMS Central’s gateway:
Queued (0) + Delivered (90) + Bounced (10) = 100 SMS
It might happen that the number of Bounced goes down, while the number of delivered goes up. This could happen when the bounces are “soft”. So if the recipient had no reception and then comes back to civilisation, the message finally goes through. Hence:
Queued (0) + Delivered (98) + Bounced (2) = 100 SMS