Why a backup is worth having
Fibre outages are uncommon but not rare. Roadworks dig through cables, equipment at the exchange fails, and building works damage internal cabling. When the line goes down, cloud phones stop, cloud apps become unreachable, card terminals that use the network stop taking payments, and staff end up hotspotting from their own mobiles. An outage of a few hours can cost a small business far more than a year of backup connection fees. Count what an outage costs you: staff wages for the time they cannot work, lost sales, missed calls and the reputational effect on clients. That number tells you how much to spend on a backup and how fast it needs to take over.
4G and 5G wireless backup
A wireless router or a SIM inside your business firewall gives you a second connection over the mobile network. It is cheap to run, quick to install and, crucially, uses an entirely different path from your fibre. With good coverage, 4G or 5G can run phones, email and cloud apps for a small office for the duration of an outage.
Check coverage inside your premises, not just on a map; concrete buildings and basements can block signal. An external antenna can help. Choose a business data plan with enough allowance for an outage day, or one that only charges for what you use. Ideally pick a mobile network different from your fibre provider's, to reduce shared points of failure.
A second fibre connection
A second fibre service gives fast, stable backup with full capacity, and suits offices that move lots of data or cannot tolerate slower speeds during an outage. For it to be useful, it should ideally come into the building by a different route or use a different provider's network; two fibres sharing the same duct can both be cut by the same digger. It is more expensive and slower to install than wireless backup, and in some buildings diverse paths are simply not available. Ask providers about route diversity and be realistic about whether a second fibre is truly separate from the first.
Starlink as a backup
Starlink connects to satellites rather than ground infrastructure, so it is independent of local fibre and mobile networks. It is a strong backup option for rural sites, offices with poor mobile coverage, and businesses that want protection against wider regional outages. It needs a clear view of the sky and a mounting position for the dish. Latency is higher than fibre but usually fine for calls and cloud apps, with occasional brief interruptions. Starlink has business plans and plans with different data allowances; check current options. Installation involves mounting and cabling the dish; any new power circuit must be done by a registered electrician.
How automatic failover works
A backup connection is only useful if it takes over without someone noticing and plugging cables in. A business firewall or router with two internet ports, or one built-in wireless modem, monitors the main connection. When it fails, traffic switches to the backup within seconds, and switches back when the main line recovers.
Some things may reconnect after failover, such as active video calls or VPN sessions, and services that rely on your static IP may not work on the backup. Plan for those: let remote staff know, and check whether any systems whitelist your office address. Test failover every few months by unplugging the fibre at a quiet time.
Choosing what suits your office
For a typical small urban office, wireless backup with automatic failover is the sensible baseline. If mobile coverage is weak indoors or the business depends heavily on uploads, consider a second fibre with diverse routing or Starlink. Rural sites with no fibre may use Starlink as the main connection and 4G or 5G as backup.
Costs differ a lot between the options. A wireless backup often costs a modest monthly fee plus a one-off router or SIM setup, a second fibre costs roughly what your main plan costs, and Starlink adds hardware plus its own monthly plan. Prices change, so get current quotes. Weigh each against your outage cost estimate from earlier; for most small offices the cheapest option that genuinely uses a separate path is the right one, and anything beyond that is insurance you should only buy if the numbers support it.
Whatever you choose, include it in your business continuity plan, document how to check which connection is active, and monitor both links. A backup that silently stopped working months ago offers no protection on the day you need it. Ask whoever manages your network to alert you when either link goes down, so a failed backup SIM or an expired data plan is fixed in a quiet week rather than discovered during an outage.
In short
- A backup connection should use a different physical path from your fibre.
- 4G or 5G with automatic failover suits most small offices.
- A second fibre needs route diversity to be truly independent.
- Starlink is a good backup where mobile coverage is weak or sites are rural.
- Test failover regularly and monitor both connections.