Fi-Wi for Low-Latency, High-Density Wi-Fi

Umber Networks is building a fiber-wireless architecture that centralizes control, keeps queues at the radio edge, and makes Wi-Fi behave like a predictable, L4S-friendly bottleneck.

Read the Fi-Wi & L4S Architecture Engineering Portal Login

Designed for MDUs, enterprise, and dense IoT environments where latency and coordination matter.

Fi-Wi Conceptual Data Path -------------------------- End Host ↓ L4S TCP/QUIC Fi-Wi Concentrator ↓ Fi-Wi fronthaul (fiber / copper) Remote Radio Head (RRH) ↓ 802.11 MAC/PHY with aggregation Wi-Fi Client / IoT • Centralized control & pacing • Time-synchronized RRHs • L4S-aware ECN at the RRH queue

Why Fi-Wi?

Traditional Wi-Fi deployments scatter fully independent access points throughout a building. Each AP has its own queues, its own contention loop, and its own retry behavior. Latency becomes unpredictable, and modern congestion control (like L4S) only sees a noisy, end-to-end signal.

Umber’s Fi-Wi system moves the intelligence into a central concentrator and treats Remote Radio Heads as coordinated, time-synchronized endpoints. The result is a single, well-behaved bottleneck that can be explicitly controlled and measured.

Centralized scheduling
Low, predictable latency
802.11 aggregation preserved
L4S-friendly ECN marking
Building-scale coordination

Technical Whitepaper

For engineers and architects, we maintain a detailed write-up on how Fi-Wi integrates with L4S, how timestamp-synchronized marking works, and how the dual control loops are structured:

Fi-Wi Architecture & L4S: Timestamp-Synchronized Control Loops

Engineering Access

Internal tools and additional documentation are available behind the engineering portal. If you have been provisioned with an account:

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