In recent Apple Mac OSX 10.13.2 system update, a new daemon called 'rapportd' has been found to do the following:
* It is an undocumented 'Rapport Connectivity Framework' (RCF), * Port 49158/tcp * It is not power-friendly, wakes up the entire box too often * systemstat starts this rapportd daemon * RCF is a multi-client chatty protocol * iPhone and iPad makes effort to connect with iMac
It's ill-conceived and not well thought out. https://discussions.apple.com/message/32698485?