It is Dynamic DNS service for EGI Federated cloud.
Users can register their chosen meaningful and memorable DNS host names in given domains (e.g. my-server.vo-name.fedcloud.eu) and assign to public IPs of their servers hosted in EGI Federated Cloud.
Just log in to the portal using EGI account and register your own hostnames. Fololow instruction after host creation for updating IP address.
A short tutorial is available at wiki