Active Multi-Link
Several links carry traffic at once, so there is no cold standby to bring up.
Branch WAN failoverWAN resilience
Keep Every Branch Online When a Link Goes Down
Customer problem
One Link Is One Point of Failure
Branches depend on the network for core banking, point-of-sale, billing and dispatch. When the link drops, the branch cannot do its job.
Links fail for ordinary reasons: a cable cut, a provider outage, a local power loss. Some do not fail outright but become slow and unstable, which can be just as disruptive.
Backups often sit idle and untested.
- Branches offline when the only link fails
- Idle backup links that are never tested
- Failover only on a hard link-down
- Primary and backup from the same carrier
- Slow, unstable links that disrupt users
- Outages discovered when the branch calls
THE COSGRID SOLUTION
Multi-Link Resilience at Every Branch
ReFleX-Edge appliances connect to every available link, including multi-SIM 4G/5G, and Guider holds policy and shows link status across sites. If a link fails or degrades, traffic moves to the links that remain. Outcomes depend on how many independent links a site has.
With ReFleX WAN, organisations can
- Run several links at once instead of an idle backup
- Move traffic off links that fail or degrade
- Bond multiple 4G/5G SIMs as a second path
- Protect real-time traffic with packet cloning
- See link health across branches in Guider
How It Works
Connect and Define Policy
Give each branch two or more links, ideally from different providers or technologies, then set application preferences and link thresholds in Guider.
Measure Every Link
ReFleX-Edge continuously probes round-trip time, jitter and packet loss on each path.
Steer and Fail Over
Traffic is steered across healthy links. When a link fails or degrades, flows shift to the remaining links, and packet cloning can protect calls.
Alert and Restore
Guider shows the affected branch and link. When the link recovers and meets policy, traffic can use it again.
Key Benefits
Failover on Degradation
Traffic can move off a link that is losing packets or adding delay, not only one that is dead.
Cellular Resilience
4G/5G multi-SIM bonding gives a path that does not share the branch's cable route.
Real-Time Protection
Packet cloning can send voice over two links at once. Forward error correction is also available.
Central Visibility
An SLA dashboard with NetFlow/IPFIX analytics shows which branches are running on fewer links.
NexusShield Sites
Where a NexusShield firewall is the site device, it supports failover and 5G multi-SIM too.
Traditional Branch WAN vs Resilient SD-WAN with ReFleX WAN
Traditional Branch WAN
- One primary link, idle backup if any
- Failover only when a link is fully down
- Backup untested until needed
- Same provider for primary and backup is common
- Outages discovered when the branch calls
- Real-time traffic drops during a switch
Resilient SD-WAN with ReFleX WAN
- Several active links in use at once
- Failover can trigger on loss, jitter or delay too
- All links carry traffic, so problems show up early
- Links from different providers and cellular networks
- Link health visible centrally in Guider
- Packet cloning can protect calls across two links
Use cases
Built for every outage scenario
Stay online while the cable is repaired
Traffic moves to the second broadband or 4G/5G link instead of the branch staying offline until repair.
Keep working on another provider's link
Branches with links from another provider or a cellular path keep working on those links.
Move off a poor link before users notice
Probes detect rising loss or jitter, and traffic can move to a better link before users suffer dropped sessions.
Protect calls across two links
Packet cloning can carry the call over two links at once, so the loss of one path has less effect.
Who Is This For
Planning the link mix first? See "Move branches off MPLS onto broadband and 4G/5G"
- CIOs
- Network Heads
- Branch & Store Operations
- Warehouses & Logistics Sites
- Remote Sites
FAQs
Have a question about branch WAN failover with ReFleX WAN?
What is branch WAN failover?
Branch WAN failover moves a branch's traffic from a failed or poor link to another working link. With SD-WAN, several links are usually active at once, so traffic shifts between them instead of waiting for a backup to start.
Does ReFleX WAN keep a branch online through any outage? No network can promise that. ReFleX WAN reduces the impact of individual link failures by using several links and moving traffic to the healthy ones. If every link at a site fails, the site goes offline. Links from different providers and technologies make that less likely.
How fast is failover? It depends on the links, the policy and the type of failure. We do not publish a general figure. A resilience assessment can test failover behaviour on your own links.
