By the SightShield team · · 3 min read
When the internet stops, so does work
Cloud software, video calls, billing systems, UPI payments, cloud telephony and remote CCTV all depend on the internet. A single fibre line can be cut by road digging, a damaged pole or an outage at the provider, and repairs can take hours or days. For most businesses, a second internet connection that takes over automatically is cheap insurance.
Building blocks
| Component | Role |
|---|---|
| Primary business fibre | Main connection with good speed and support |
| Second ISP | Different provider, ideally on a different physical route |
| 4G/5G router | Backup where a second fibre is not available |
| Dual-WAN firewall or router | Detects failure and switches traffic |
| Static IP (if needed) | For VPNs, servers or remote access rules |
Failover or load balancing?
- Failover: all traffic uses the primary line; the backup takes over only when it fails.
- Load balancing: traffic is spread across both lines, using the combined capacity.
- Policy routing: calls and critical apps use the better line; bulk downloads use the other.
- Most small businesses start with failover and add policies later.
Truly independent lines
Two providers sharing the same cable route along the same road can fail together when a backhoe cuts the duct. Ask each provider how their cable reaches your building, and prefer different entry points or one wired line plus a wireless 4G or 5G backup. In multi-tenant buildings, check with the facility team which providers already have fibre in the riser.
What breaks during a switchover
- Video calls and VoIP calls drop and must reconnect.
- Remote access using a fixed public IP needs the backup line’s IP configured too.
- Some payment terminals and banking portals need re-login.
- Cloud-based CCTV viewing reconnects automatically through the brand’s service.
Branches and SD-WAN
Businesses with several branches can use SD-WAN, which manages multiple internet links at each site, routes traffic by application, and links branches securely. It replaces older leased lines for many retail chains and clinics. For one or two sites, a good dual-WAN firewall is usually enough.
Test it
- Unplug the primary line during a quiet hour and check that everything keeps working.
- Confirm alerts reach IT when a line fails.
- Check the backup line’s speed is enough for essential work.
- Repeat after any change to the firewall or provider.
Choosing the primary line
- Business fibre with a service level agreement for repairs, not a home plan.
- Upload speed matters for video calls, cloud backups and remote CCTV viewing.
- Ask for typical repair times in your area and an escalation contact.
- Get a static IP only if you host services or use site-to-site VPNs.
An example
A diagnostic centre in Malleshwaram lost its only fibre line for a full day when road work cut the cable, stopping reports, payments and calls. It added a second provider entering the building from the opposite side and a dual-WAN firewall with failover. Months later, another cut took the primary line down for six hours; staff noticed only a brief pause on one video call.
Set it up with us
We install dual-WAN firewalls, coordinate second lines and 4G/5G backup, and test failover end to end.
IT networking services →Quick answers
Does a small business need two internet lines?+
If billing, calls or cloud software stop when the internet fails, a second line is worth it.
Is 4G backup good enough?+
For essential work during outages, often yes; check signal strength and data limits.
What is the difference between failover and load balancing?+
Failover uses the backup only when the primary fails; load balancing uses both together.
Will calls drop during failover?+
Active video and VoIP calls usually drop and reconnect; most other work continues.
How do I know if the backup line is working?+
Set up alerts on the firewall and test failover by unplugging the primary line during a quiet hour.
Should both lines be the same speed?+
Not necessarily. The backup needs enough speed for essential work, not everything.
What is SD-WAN?+
Software that manages multiple internet links and connects branches securely, routing traffic by application.