Author

Lasse Johnsen

Co-founder & CTO, TimeBeat

Lasse Johnsen is co-founder and CTO of TimeBeat. He leads hardware engineering, firmware and the linuxptp software stack that powers the TimeBeat platform. His work spans FPGA design for sub-nanosecond White Rabbit nodes, OCXO/Rubidium holdover characterisation and the BMCA implementations behind TimeBeat's grandmaster fleet. Lasse contributes to the linuxptp open-source project and the OCP Time Appliance Project.

Expertise

linuxptpFPGA timing designWhite RabbitHoldover oscillator characterisationBest Master Clock Algorithm

LinkedIn ↗GitHub ↗

Articles

Written by Lasse

pillar22 min

PTP Grandmaster Clock: The Complete 2026 Guide

What a PTP grandmaster clock actually does, how to choose one, and what separates a grandmaster you can trust from one that quietly drifts. Written by TimeBeat's engineering team for network architects deploying IEEE 1588 in production.

pillar24 min

5G Fronthaul Timing: The Complete 2026 Guide

How precision timing actually works in 5G fronthaul networks — the time-error budget, the ITU-T accuracy classes, the role of G.8275.1, and what it takes to operate a fronthaul timing fabric without dropping calls or losing handovers. Written by TimeBeat's engineering team for mobile network operators and O-RAN integrators.

pillar20 min

PTP Jitter Attenuation: How TimeBeat Cleans the Clock Signal

What jitter attenuation actually does inside a PTP timing fabric, why raw timestamps are unreliable, and how TimeBeat's signal-processing engine delivers sub-nanosecond residual noise from noisy real-world inputs. Written by TimeBeat's engineering team.

cluster14 min

OCXO vs Rubidium Holdover: When Each Oscillator Class Earns Its Place

Choosing between OCXO, double-OCXO and rubidium holdover oscillators in a PTP grandmaster — the drift numbers that matter, the deployment scenarios where each is correct, and the trade-offs nobody talks about.

cluster15 min

PTP Profile Selection: G.8275.1, G.8275.2, ST 2110 and the Default Profile

Choosing the right PTP profile is the difference between a deployment that works on day one and one that needs three weeks of debugging. A practical guide to G.8275.1, G.8275.2, ST 2110 and the IEEE 1588 default profile — what each is for, what defaults matter, and how to mix them.

cluster12 min

ITU-T G.8275.1 Explained: The Telecom PTP Profile for 5G Fronthaul

What ITU-T G.8275.1 actually specifies, why it's the only PTP profile that meets the 5G fronthaul time-error budget, and what to look for in a grandmaster claiming G.8275.1 support.

cluster13 min

O-RAN Fronthaul Sync: How Open RAN Networks Get Their Time

Open RAN architectures have specific timing requirements baked into the O-RU / O-DU split. A guide to the LLS-C1, LLS-C2, LLS-C3 and LLS-C4 sync configurations, what each demands of the timing fabric, and how to operate them in production.

cluster14 min

Oscillator Tier Selection: OCXO vs Rubidium Black vs Rubidium Black+

An engineering decision framework for picking oscillator tier on an Open Time Appliance. Drift maths that matter, real-world holdover scenarios, and where each tier is the right economic answer — not just the best spec sheet.

cluster15 min

The 167 Telemetry Fields — What Timebeat Agent Actually Measures

An engineering-level tour of the 167 telemetry fields the Timebeat Agent emits per cycle to Sync Insight. Nine measurement domains, why each one matters for operations or compliance, and how to pick the handful of fields your Grafana dashboard actually needs day-to-day.

cluster12 min

Clock Ensemble: Multi-Source Clock Fusion Inside the Timebeat Agent

How the Timebeat Agent fuses GNSS, upstream PTP feeds, PPS inputs and oscillator discipline into a single weighted clock output — the same BIPM-style ensemble approach used to produce UTC itself, applied at the site level.

cluster14 min

PTP² Mesh: Self-Healing Timing Topology Across the Timebeat Agent Fleet

How PTP² Mesh turns a fleet of Timebeat Agents into a self-discovering, self-healing time distribution network. mDNS and DHT peer discovery, seat-based capacity, active-active operation and millisecond failover — for when you need redundancy without the rigidity of classical BMCA hierarchies.

cluster11 min

VGMC — The Virtual Grandmaster Clock Pattern

A virtual grandmaster clock is an IP endpoint that looks like a single PTP grandmaster to downstream clients but is backed by multiple physical Timebeat Agents — redundancy, capacity and failover at the topology level, with a single client-facing configuration.

Want to talk to Lasse?

The TimeBeat engineering team is happy to discuss timing architecture, deployment patterns and the operational realities of running production PTP fabrics.

Book an engineering call