Most businesses only think about backup broadband after the first time their connection goes down. Suddenly the card machine will not connect, calls stop ringing and the team cannot reach the files they need. Full fibre is a reliable technology, but no single connection can promise never to fail.
A backup connection, with failover set up properly, means an outage becomes a minor inconvenience rather than a lost day. This guide explains the options and how to choose.
What causes business broadband outages?
Knowing what goes wrong helps you choose a backup that avoids the same weak point.
- Physical damage. Cables can be cut during roadworks or building work, or damaged by vehicles and bad weather.
- Equipment faults. Routers and network equipment in your building can fail, or lose their settings.
- Network faults. Problems further along the network, at a cabinet, exchange or data centre, can affect many customers at once.
- Power cuts. If your router has no power, your connection is down, even if the line itself is fine.
- Planned work. Networks occasionally carry out maintenance, which is usually scheduled out of hours but can still affect businesses that work around the clock.
What is failover?
Failover means your network switches to a second connection when the main one stops working. There are two broad approaches.
Automatic failover
A router that supports two connections, often called a dual WAN router, watches the main line. When it detects a problem, it moves traffic to the backup, and moves it back when the main line recovers. Staff may notice a brief pause, and calls or video meetings in progress may drop, but most things carry on.
Manual failover
Someone notices the outage and switches over, for example by plugging in a mobile router or turning on hotspots from work phones. It costs less to set up but depends on a person being there, knowing what to do and remembering where the equipment is.
Backup broadband options
4G or 5G mobile backup
A mobile router with a data SIM is the most common backup for small businesses. It uses a completely different path from your fixed line, so a cut cable in the street will not affect it. It suits card payments, email, cloud software and calls well.
The main limit is signal. Mobile coverage varies inside buildings, especially in basements, steel framed units and older stone buildings. Test the signal where the router will sit, and consider an external antenna if it is weak. Check the data allowance too, so a long outage does not leave you stuck.
A second fixed line
A second broadband connection gives you a backup that behaves much like your main line. It works best when the two lines are genuinely separate: different networks, or at least a different route into the building. Two lines from the same cabinet, sharing the same duct, can both be taken out by one digger.
Leased line with a backup circuit
Businesses on a leased line often pair it with a broadband or mobile backup, or for critical sites a second circuit. Leased lines are usually supported by faster fault fix targets, but a backup still covers the time it takes to repair a cut fibre.
Diverse routing
For businesses where downtime is very costly, a backup can be designed to take a physically different route, entering the building at a different point and connecting to a different part of the network. This is the strongest protection and is usually quoted per site.
How to choose the right backup
Start with what an outage actually costs you and what must keep working.
- Which systems are essential? Card payments, phones and a booking system may matter more than large file downloads.
- How long could you cope without a connection? An hour, a morning, or not at all?
- How much speed do you need on backup? Often much less than on your main line, because you only need to keep the essentials running.
- What signal and networks are available? This decides whether mobile backup or a second fixed line is the practical choice.
Our guide to how much broadband speed a business needs can help you work out what is essential.
Things failover does not fix on its own
Power
A backup line will not help if the router has no power. A small uninterruptible power supply, often called a UPS, can keep your router, network switch and phones running through short power cuts.
Static IP addresses
Your backup connection will usually have a different public IP address from your main line. If you rely on a static IP for remote access, VPNs or allowlisting, plan how those will work on backup, for example by adding the backup address to your allowlists.
Phone calls
Internet based phones can move to the backup line automatically, but calls in progress may drop during the switch. Many hosted phone systems can also divert calls to mobiles if your office goes offline. Our guide to VoIP and your broadband explains more.
Problems inside your network
If a network switch fails or your WiFi drops, a backup internet line will not help. Keep spare cables to hand and know who to call.
Test your backup before you need it
A backup that has never been tested is a hope, not a plan. Once it is set up:
- Unplug the main line during a quiet period and check that everything essential still works.
- Take a card payment, make a call and open your key cloud systems.
- Reconnect the main line and check that traffic moves back.
- Repeat every few months, and check that any SIM is still active and has data.
Write down what staff should do if the connection drops, including who to contact and where the backup equipment is.
Talk to us about keeping your business online
We can help you think through what you need to protect and which backup makes sense for your premises. Check your address for business full fibre, request a leased line quote, or contact our team in Sunderland to talk through backup options.