SpeedFusion 101 — the bonding engine
If your disaster recovery plan includes the word “failover,” you’re doing it wrong.
SpeedFusion bonding means more performance and more uptime — with no failover, because the session was already riding every path.
SpeedFusion is a tunnel between two endpoints that splits a session across many links and reassembles it at the far end. That two-endpoint rule is the single most important fact: bonding, smoothing and FEC all need something on the far side (another Peplink, a FusionHub, or a hosted endpoint). A lone router with no partner gets only load-balancing and failover — not true bonding.
Bonding vs. hot failover vs. load balancing
Bonding splits one session across all links for combined throughput. Hot failover pins the session to one link but moves it in under a second if that link drops — the call never drops. Load balancing spreads separate sessions (no tunnel needed). Old-school failover drops and reconnects; SpeedFusion never does.
Dynamic Weighted Bonding (always on)
DWB measures each link’s throughput, latency and loss moment to moment and shifts the mix in real time — a strong 5G link carries more, a struggling Starlink carries less, so one bad path never drags the bond down. Most “bonding is broken” tickets are really DWB correctly avoiding a misbehaving link.
WAN Smoothing & Forward Error Correction
Smoothing duplicates each packet across links and uses the first copy to arrive — zero-loss for real-time traffic, but its value comes entirely from path diversity and it is the most expensive feature in the catalog. FEC adds parity so the far end rebuilds a lost packet without a retransmit — far cheaper, works even on one link. Rule: reach for Adaptive FEC first; reach for smoothing last, and only on a dedicated real-time sub-tunnel.
Sub-tunnels & Boost
Sub-tunnels run parallel tunnels between the same two endpoints so you apply expensive protection surgically — voice on a smoothed sub-tunnel, bulk transfers on a plain bonded one. Boost accelerates a single high-latency link (5G, Starlink), the honest answer to “I only have one connection.”
Overhead at a glance
Every feature costs bandwidth. Size to the real numbers (West Networks lab + Peplink’s SpeedFusion Whitepaper), and apply protection only where it’s needed:
| Feature | Overhead | Use when |
|---|---|---|
| Bonded baseline (DWB, encryption) | ~14–18% | Always — the floor |
| Each added sub-tunnel | ~0–2% | Segmenting traffic types |
| Adaptive FEC | ~6–20% | Default on a lossy/single link |
| FEC (standard) | ~13% Low / ~27% High | Measured moderate loss |
| SpeedFusion Boost | ~10–15% / link | Single high-latency link |
| WAN Smoothing | +100% Normal → +300% High → +400%+ Max | Real-time, multi-path only |
From the field
- Mobile mammography bonded five cellular links into one reliable connection to move diagnostic images where single cellular and satellite had failed at any price.
- HYROX Chicago 2025 bonded six Starlinks with cellular — registration and live timing never dropped as links wobbled. Not “we have a backup” (failover), but “we don’t go down” (bonding).
- Heathgate Resources reached ~1.3 Gbps for 250+ workers bonding Starlinks to a FusionHub after a fire cut the mine’s microwave link — Boost kept the slower dishes from dragging the fast ones down.
Which router runs it best for your job? Peplink 101 → · Browse the line: Peplink Products →