Choosing a Second ISP: How to Get Real Redundancy
Adding a second internet connection is the most common resilience upgrade — and one of the most commonly done badly. Many organisations discover during an outage that both links failed together.
Questions to ask
- Different physical path? Ask both providers for route maps from your building to their PoP.
- Different building entry? Two cables in the same riser fail together.
- Different last-mile owner? Some providers resell the same access network.
- Different upstream networks? Two ISPs buying transit from the same carrier share its outages.
- Different technology? Fibre plus radio or 5G is naturally diverse.
Making failover work
- Without your own IP space, failover changes your public IP — fine for outbound browsing, not for hosted services or site-to-site VPNs unless they are designed for it.
- With your own ASN and IPs, BGP makes both links active and failover seamless.
- SD-WAN can use both links actively and steer applications intelligently.
Test regularly
Disconnect the primary during a maintenance window every few months and confirm everything — VPNs, voice, cloud apps — keeps working.
We source diverse connectivity and design the failover. See our Transit service or ask for a diversity check.
