* @send_msg: routine which handles buffer transmission
* @enable_media: routine which enables a media
* @disable_media: routine which disables a media
* @addr2str: routine which converts media address to string
* @addr2msg: routine which converts media address to protocol message area
* @msg2addr: routine which converts media address from protocol message area
* @send_msg: routine which handles buffer transmission
* @enable_media: routine which enables a media
* @disable_media: routine which disables a media
* @addr2str: routine which converts media address to string
* @addr2msg: routine which converts media address to protocol message area
* @msg2addr: routine which converts media address from protocol message area