Understanding the Problem
In rural areas, broadband infrastructure can be vulnerable to unexpected disruptions. At one of our sites in Kent, the primary FTTC connection suddenly failed without warning. Initially, this looked like a routine outage, but reports from staff on social media suggested something more serious: copper cable theft affecting several nearby villages.
When the ISP confirmed the cause, it became clear this would not be a quick fix. With the primary connection offline and no immediate resolution in sight, we needed a reliable way to restore essential services and maintain remote access.
Choosing LTE as the Backup Path
The quickest and most practical solution was to deploy an LTE modem. We selected a compact device that could be installed on‑site with minimal disruption. A prepaid data SIM was used to bring the connection online, and the network provider offered a public IP address suitable for remote access.
Once the modem was configured, the site had a working internet connection again. This allowed essential services, such as email, to resume while the primary broadband remained offline.
Restoring Email Through DNS Failover
To ensure email continued to flow, we added a secondary MX record pointing to an address updated automatically by the firewall’s dynamic DNS service. This meant the on‑site mail server could send and receive messages over the LTE connection without requiring any changes from users.
This approach kept communication running smoothly throughout the outage, even though the primary broadband was unavailable for several days.
A Single On‑Site Visit for Long‑Term Resilience
Setting up the LTE modem required one visit to the premises, as remote access was unavailable at the time. Once installed, however, the modem became a permanent part of the network’s resilience strategy. All further configuration and monitoring could be handled remotely.
This reflects a broader principle in our work: if a site visit is necessary, we use the opportunity to reduce the need for future visits.
Adding a Secondary VPN Path
With the LTE connection in place, we configured a second VPN endpoint on the firewall. This provided an alternative route into the network whenever the primary broadband was unavailable. From that point on, even if the FTTC line failed to reconnect cleanly, we could still access the site through the LTE link.
This secondary VPN path proved valuable on several occasions, allowing remote maintenance and troubleshooting without waiting for the primary connection to recover.
The Outcome
The FTTC line was restored five days after the incident, but the LTE modem remained in place as a permanent safeguard. It provided:
- a reliable backup internet connection
- uninterrupted email delivery during outages
- a secondary VPN path for remote access
- improved resilience for future incidents
What began as an emergency response became a long‑term improvement to the site’s connectivity.
Engineering Philosophy
This experience reinforced several principles that guide our approach to infrastructure:
- plan for real‑world failure modes
- keep solutions simple and maintainable
- use technology that can be deployed quickly
- ensure remote access is always available
- turn temporary fixes into permanent improvements
By adopting LTE as an emergency connectivity layer, we ensured that essential services remained available even during extended outages.