Some broadband ISP customers on Cityfibre’s national Fibre-to-the-Premises (FTTP) network, which covers 4 million UK premises, are currently experiencing ongoing connectivity problems due to an unspecified issue that seems to only be affecting those that have one of Nokia’s Optical Network Terminals (ONT) installed inside their building.
Just for context. The ONT / ONU or optical modem device is usually installed inside your home or office (wall hung), near to where the fibre optic cable physically enters your property, and its primary job is simply to take the optical signal and convert it into an electrical one that can be connected to your broadband router via a Local Area Network (Ethernet) port. The standard ONT is usually a very small single port device.
Most of the residential customers on CityFibre’s network are probably connected using the ONT supplied by Calix, which tend to be coloured black (there are several models in circulation, but they’re usually the same colour). By comparison, Nokia‘s ONT is more of a cream white colour and has rounded edges. This is most commonly found in CityFibre’s newer XGS-PON (10Gbps) areas (roll-out update), although Calix also do some of the XGS-PON kit.
However, several of ISPreview’s readers from different parts of the UK have been reporting problems with Nokia’s ONT units since just after 8pm last night, which has also generated a related post on Reddit. As one of our readers (Jonny) said this morning: “My connection went down at 20:30 last night and [my ISP] have confirmed a wider network issue to me in a support ticket. Symptoms are a steady flashing PON light, which is supposedly indicative of a firmware update. Outage has so far been 15 hours.”
The fault is not believed to be impacting too many of CityFibre’s connections and as a result we haven’t seen many of their ISPs putting out a notice about it yet, although we did get this from No One Internet (Leetline).
Jan 09, 10:09 AM
CityFibre is aware of an issue impacting a small number of FTTH and business FTTP customers. We have engaged with our technical teams who are currently investigating to resolve the underlying issue as quickly as possible, and we are also working to minimise impact to those customers who are affected. We apologise for any inconvenience this is causing.
We have asked for a comment from CityFibre too and will report back when one arrives. The hope is that this fault can be rectified remotely, but if it is a problem with a borked firmware update, then those can sometimes only be rectified by a device replacement. But at this time, the specifics are not clear on what has actually gone wrong.