Static IP
You can request a static IPv4 (address) at the network tutor. Only a few static IPv4 addresses are available. The request has to include a substantial motivation. Requesting a static IP for remote access for example is not a sufficient reason, because this can be done by DynDns service using ports 50000-50010. Using an own server is mainly the standard reason for a static IP. If a user is allowed a static IPv4, he will receive a special user name for the Internet login. After login with this user name he will get the static IP.
Without an assigned IPv4 address, a login using zxxxxx-ip1 is also possible. In this case a dynamic IPv4 address and a static IPv6 prefix will be assigned.
When using a static IP, more ports are open as when using a dynamic IP. More information on this below Firewall.