The re.rockspace.local IP address is the default IP address for a WiFi extender, and it is used for troubleshooting and configuration. The re.rockspace.local is a unique address that your router uses to connect to your extender. It's used to help the extender establish a connection with the router and make sure that it can be found by other devices in your network. This address is not visible or accessible to users when they're connected via wifi, so you don't need to worry about someone else being able to access it. Simply put, the re.rockspace.local domain is a unique service for Rockspace users. It allows users to setup and customizes the Rockspace wireless extender.