In the event that the DHCP server or DNS server do not support or permit DDNS updates, then the DNS server database will need to be manually configured. Also, because these updates are not occurring, all of the machines should have fixed pre-assigned IP addresses. This is not strictly necessary for clients, since they will not have incoming DICOM connections, but may be needed for other reasons. In practice maintaining this file is very similar to the maintenance of the older hostname files. There is still a significant administrative gain because only the DNS and DHCP configuration files need to be maintained, instead of maintaining files on each of the servers and clients