Kannel is an WAP and SMS gateway. WAP is short for Wireless Application Protocol, and is used to
implement hypertext based services on mobile phones. SMS is short for Short Message Service, and is used
to send and recive short (up to 160 characters) text messages with mobile phones. SMS can also be used
to implement simple text based services on mobile phones.
Kannel consists of three programs, usually run as daemons: bearerbox, wapbox, and smsbox. They implement
the connection to the phone (SMS or UDP), the WAP protocol stack, and the SMS based services,
respectively.
For more information, see http://www.kannel.org or file:///usr/share/doc/kannel/.