I have repeatedly experienced problems whereby the Business Hub stops issueing IP addresses after around 6 weeks of installation to wireless devices. I have experianed this on 2 Business Hub 3's, a Business Hub 2 and also a Home Hub 4. The wireless devices recognise the Hubs SSID but no IP address is issued to the devices. Switching off then on the power supply to the Hub does not resolve these issues.
The hub is used in a small business where there are 4 wired Desktops and, on average, about 12 wireless devices.
The IP range is set to 192.168.1.5 to 192.168.1.250. The Hub is connected to an BT Infinity modem.