Kannel is a gateway for connecting WAP (Wireless Application Protocol) phones to the Internet. It also works as an SMS/SMPP gateway, for providing SMS based services for GSM phones.

Sqlbox is a special Kannel box that sits between bearerbox and smsbox and uses a database queue to store and forward messages.

Messages are queued on a configurable table (defaults to send_sms) and moved to another table (defaults to sent_sms) afterwards.

You can also manually insert messages into the send_sms table and they will be sent and moved to the sent_sms table as well. This allows for fast and easy injection of large amounts of messages into Kannel.