The device will always return his hostname. At the delivery time to the customer a default value is already present. The default value consists of the device type and the second half of the MAC address of the device. As far as he is concerned the customer can write his own hostname later. The hostname must have a length of 2 to 63 characters. Only letters, numbers and hyphens (apart from the first character) are allowed. If the hostname resolution is enabled, the device can be reached via his hostname. If mDNS is used for name resolution an additional .local suffix is appended to the hostname.