Spectrum, timing and PNT
PRTC and enhanced PRTC
GNSS-traceable time references at 100 ns or 30 ns accuracy that anchor a timing network.
We design, deploy, operate and maintain.
ITU-T G.8272 (PRTC) · ITU-T G.8272.1 (ePRTC)
Grandmasters and holdover: the clock keeps time from its oscillator when the sky goes dark. The loop, step by step: 1. A grandmaster, its antenna and a rack of radios. 2. Sensor, link, edge and console stand ready. 3. Satellite time disciplines the oscillator. 4. Time and place are fixed to every sample. 5. The antenna loses its view of the sky. 6. The edge verifies every signature first. 7. The grandmaster switches to holdover. 8. Only a confirmed result leaves the edge. 9. The oscillator keeps phase within the limit. 10. Instruments confirm the response took effect. 11. The rack still receives one clean beat. 12. Relays carry the packets without reading them. 13. Operators see the drift budget count down. 14. The console shows the evidence with the alert. 15. Record, proof and action are archived together. 16. The sky returns and the clock re-locks.
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A grandmaster, its antenna and a rack of radios
Nexus Observatory/
Positioning, navigation and timing/
Grandmasters and holdoverReference clocks that keep time when the sky goes dark.
Grandmasters and holdover, inside Positioning, navigation and timing: PRTC and enhanced PRTC, primary reference clocks for frequency, atomic and quartz oscillators, holdover design and more. Every item is traced to its specification, from ITU-T G.8272 (PRTC) to ITU-T G.8272.1 (ePRTC), and runs on the open Observatory Protocol.
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At a glance
PRTC and enhanced PRTC
GNSS-traceable time references at 100 ns or 30 ns accuracy that anchor a timing network. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds PRTC and enhanced PRTC, drawn against ITU-T G.8272 and ITU-T G.8272.1 and used beside traceability to national time scales on the same sites.
Inkinga
Reference clocks that keep time when the sky goes dark
Positions drive autonomous trucks; timestamps order every event in a network. When a receiver is jammed or spoofed, both can be wrong while looking perfectly normal. Integrity has to be designed and measured, because a degraded signal rarely announces itself to the systems that depend on it.
Key facts
- Specification
- ITU-T G.8272 (PRTC) · ITU-T G.8272.1 (ePRTC)
- Specification
- ITU-T G.810 (definitions and terminology) · ITU-T G.8260 (time and phase metrics)
- Specification
- ITU-T G.8272.1 (ePRTC with autonomous time reference) · ITU-T G.811.1
- Specification
- ITU-T G.8273.2 (holdover performance) · ITU-T G.8272.1
- Specification
- ITU-T G.811 · ITU-T G.811.1 (ePRC)
Components
- PTP grandmaster clock with GNSS antenna
- Robotic total station in a monitoring shelter
- Slope stability radar on a trailer
- Haul truck with onboard network and autonomy kit
- Private LTE mast on a solar skid
- “AI tower in a box”
- Data hall row pair with cold-aisle containment
- Operations console with a video wall
Interfaces
- Time and position
- PTP (IEEE 1588) · GNSS 1PPS · NTP
Where it works
- Timing performance monitoring
- Holdover design
In the story below
- The system, part by part
- Assembly
- Installation
- Deployment
- Connections
- Operation
- Failure and recovery
- Scale and federation
- What you get
Scenes · 13
Next steps
Plan a deploymentOpen the Field Deployment StudioSee Positioning, navigation and timingTalk to salesPositioning, navigation and timing · Grandmasters and holdover
Reference clocks that keep time when the sky goes dark
Positions drive autonomous trucks; timestamps order every event in a network. When a receiver is jammed or spoofed, both can be wrong while looking perfectly normal. Integrity has to be designed and measured, because a degraded signal rarely announces itself to the systems that depend on it.
What it does
PRTC and enhanced PRTC
GNSS-traceable time references at 100 ns or 30 ns accuracy that anchor a timing network. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds PRTC and enhanced PRTC, drawn against ITU-T G.8272 and ITU-T G.8272.1 and used beside traceability to national time scales on the same sites.
- Specification
- ITU-T G.8272 (PRTC) · ITU-T G.8272.1 (ePRTC)
Grandmasters
Timing performance monitoring
Measuring time error, MTIE and TDEV across the network to catch degradation early. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds timing performance monitoring, drawn against ITU-T G.810 and ITU-T G.8260.
- Specification
- ITU-T G.810 (definitions and terminology) · ITU-T G.8260 (time and phase metrics)
Grandmasters
Atomic and quartz oscillators
Caesium, rubidium, chip-scale atomic and oven-controlled quartz oscillators chosen by holdover needs. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds atomic and quartz oscillators, drawn against ITU-T G.8272.1 and ITU-T G.811.1.
- Specification
- ITU-T G.8272.1 (ePRTC with autonomous time reference) · ITU-T G.811.1
Grandmasters
Holdover design
Keeping time within budget for hours or days when GNSS is lost. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds holdover design, drawn against ITU-T G.8273.2 and ITU-T G.8272.1. We build it into every site for grandmasters and holdover against that standard, and keep its version and its test results on the site’s record.
- Specification
- ITU-T G.8273.2 (holdover performance) · ITU-T G.8272.1
Time and place
When and where, on every record
Every record made for grandmasters and holdover carries its time, from a clock disciplined by satellite time or a PTP grandmaster, with the position and siting record of the station that made it. When time or position degrades, the record for grandmasters and holdover says so, and every user downstream sees the same warning.
Grandmasters
Primary reference clocks for frequency
Frequency references for SyncE and legacy networks. In grandmasters and holdover, part of Positioning, navigation and timing, the grandmasters, reference clocks and holdover layer holds primary reference clocks for frequency, drawn against ITU-T G.811 and ITU-T G.811.1 and used beside edge and distributed grandmasters on the same sites.
- Specification
- ITU-T G.811 · ITU-T G.811.1 (ePRC)
Ukwethembeka
Proved before it is trusted
A node joins a network for grandmasters and holdover only after its hardware root of trust answers an attestation challenge. Its keys stay in secure hardware, its software arrives signed and every record it makes for grandmasters and holdover carries a signature, so anyone downstream can check where a value came from.
Ubufakazi
Traced to its specifications
We trace each part of grandmasters and holdover to its specification: ITU-T G.8272, ITU-T G.8272.1 and ITU-T G.811. We keep the versions, configurations and test results of grandmasters and holdover as signed records, so a buyer or an auditor can check what was delivered against what was specified.
- Amazinga
- ITU-T G.8272 · ITU-T G.8272.1 · ITU-T G.811 · ITU-T G.811.1
Izibuyekezo
Updates in rings, with rollback
Software and configuration reach a fleet for grandmasters and holdover in rings: one canary site first, then a few, then all, each ring gated on health and data completeness. A failed gate stops the wave, and each node for grandmasters and holdover returns to its last good release without a site visit.
How it scales
One base unit, repeated
A network for grandmasters and holdover starts with one base node and the instruments it reads. A station adds power and radio, a site adds a relay and a fleet repeats the proven site, so capacity for grandmasters and holdover grows by adding units, never by replacing what works.
What you get
Timing and positioning integrity
PTP grandmasters with GNSS holdover, interference detection and timing monitoring for networks and instruments. For grandmasters and holdover, it goes to carriers, utilities, financial infrastructure and observatories as hardware and software or a managed service, sized to the sites they run.
Talk to salesNext step
Grandmasters and holdover, planned with you
Tell us the sites, the systems grandmasters and holdover must work with and the outcome you need, with a map or a list of addresses if you have one. An engineer replies with a survey proposal, a design and a scope for grandmasters and holdover, and the plan grows from one site to the network you need.
Plan a deploymentOpen the Field Deployment StudioSee Positioning, navigation and timing
More presentations
See it from every side.
Each opens as a full-screen presentation: deeper pages on the same subject, explainers, stories, guided tours of the places, network scenes and the observatories that came before.
All presentationsIn depth
Use case Highway corridor coverage and safety sensingUse case Utility grid-edge private LTE and wildfire weatherUse case Wildfire camera and fire-weather nodeUse case Avalanche detection siteExplainers
Explainer · Environment and climate Environment and climate — SectorsMethane fencelines, acoustic biodiversity grids, flux towers, river sondes and smoke networks: an interactive explainer with the method behind every number.Explainer · Communities and rural Communities and ruralCommunity cellular coverage on real terrain, fixed-wireless Fresnel clearance, corridors, a remote microgrid sized from its load and interim public-safety broadband.Inkundla Positioning, navigation and timingA wrong timestamp is a wrong answerInkundla Edge compute & AIThe archive is too lateStories
Story · Timing and PNT Time as infrastructureA 5G cell must hold its phase within 3 µs of its neighbours, ±1.5 µs of a common reference; a synchrophasor’s one per cent vector error leaves room for only…Story · 6G and sensing Networks that senseThe framework for 6G names integrated sensing and communication as one of its usage scenarios: the same radio that carries data also measures range,…Story · Mountains and avalanche terrain Snowpack, slope and signalAvalanche forecasting reasons about the likelihood and size of avalanches on given terrain. The observations behind it come from a few stations in hard…Places and networks
Guided tour · Guided 3D tour Orbit viewGround tracks of a sun-synchronous imager and three shells of a broadband constellation, computed from their orbits over a rotating Earth.Guided tour · Guided 3D tour Arctic stationA self-powered station on the ice: a microgrid, a low-orbit satellite terminal, a weather station, a GNSS monument and an edge node that holds data through the polar night.Guided tour · Guided 3D tour Offshore and oceanA moored met-ocean buoy and a profiling float report through a satellite pass overhead; the red link is the uplink.Network scene · Private 5G · Port Private 5G at a container portSmall cells on the yard lighting masts and a sector site on the operations building serve remote-controlled cranes and trucks among steel container stacks.Network scene · NTN · Satellite Satellite direct to device in a mountain valleyWhere the valley cell cannot reach, phones on the pass road connect straight to a low-orbit satellite, which relays through its feeder link to a gateway.Heritage observatories
Heritage observatory · China · 132 Zhang Heng’s seismoscopeIn 132 CE a court astronomer presented a bronze urn that, it was recorded, told the capital of an earthquake no one in Luoyang had felt. No original survives.Heritage observatory · United States · 2009 Ocean Observatories InitiativeCabled and moored arrays in the Atlantic and Pacific, designed to give scientists a continuous, real-time view of the ocean for decades.Interactive tools
Interactive tool · Configure a station Station BuilderConfigure a station part by part in 3D, check the rules as you go and request a quote for the assembly.01Yini
Grandmasters, reference clocks and holdover.
The shared foundations every network and sensor depends on: how spectrum is licensed, shared and monitored, GNSS positioning and its corrections, packet timing with PTP and SyncE, grandmasters and holdover, resilient PNT alternatives, and the detection of interference, jamming and spoofing. Each technology below carries what it is, what we do with it, and the standard it is drawn against.
Spectrum, timing and PNT
Primary reference clocks for frequency
Frequency references for SyncE and legacy networks.
We design and deploy.
ITU-T G.811 · ITU-T G.811.1 (ePRC)
Spectrum, timing and PNT
Atomic and quartz oscillators
Caesium, rubidium, chip-scale atomic and oven-controlled quartz oscillators chosen by holdover needs.
We design, integrate and maintain.
ITU-T G.8272.1 (ePRTC with autonomous time reference) · ITU-T G.811.1
Spectrum, timing and PNT
Holdover design
Keeping time within budget for hours or days when GNSS is lost.
We design and operate.
ITU-T G.8273.2 (holdover performance) · ITU-T G.8272.1
Spectrum, timing and PNT
Timing performance monitoring
Measuring time error, MTIE and TDEV across the network to catch degradation early.
We operate and maintain.
ITU-T G.810 (definitions and terminology) · ITU-T G.8260 (time and phase metrics)
Spectrum, timing and PNT
Traceability to national time scales
Linking network time to UTC through a national metrology institute.
We design and support.
BIPM Circular T · UTC(NRC) (National Research Council Canada)
Spectrum, timing and PNT
Edge and distributed grandmasters
Grandmaster functions at cell sites and edge nodes to shorten timing chains.
We design, integrate and deploy.
ITU-T G.8275.1 · O-RAN WG4 CUS-Plane (LLS-C3 topology)
02Architecture
Where it sits, and what it speaks.
Grandmasters and holdover draws on the spectrum below; the highlighted layers carry this area, and the protocol functions it speaks are marked.
Spectrum regimes and access
9
Spectrum monitoring and interference management
8
GNSS positioning and augmentation
9
Packet timing: PTP, SyncE and NTP
10
Grandmasters, reference clocks and holdover
7
Resilient PNT
9
Interference, jamming and spoofing detection
7
01Joyina Identity, attestation quote, signed policy.
02Admit Admitted for a stated scope, nothing wider.
03Chaza What, where, how and by whom, with calibration.
04Time One clock across the grid, with its error bound.
05Observe Every value with quality and provenance.
06Qualify Tested against the specification, state on record.
07Federate Signed exchange across grids and trust domains.
08Orchestrate Software and configuration by signed plan.
09Correct A correction marks what depends on it and publishes a new version.
10Exchange Products reach people and applications through versioned interfaces.
11Prove Signed proof receipts that an independent verifier can check.
12Exit and decommission An open exit path, and a record that closes.
03On the grid
Every site joins one observing grid.
The open networks on the grid today, over real relief and the geodesic cells we count them into, filtered to the solid earth domain this area serves. A site built here enrols into the same grid.
The observing grid
- Open solid earth instruments on the observing grid.
04In the field
Where this runs, sector by sector.
Deployment scenarios from the sector research that rely on grandmasters and holdover.
TransportMaritime and port met-ocean with vessel tracking
Wave buoys and a receiver for vessel position broadcasts.Government and public safetyNational GBON surface and upper-air network
WMO-grade stations reporting through WIS 2.0, funded through the systematic-observations financing pathway.Government and public safetyWildfire camera network and fire-weather stations
Camera towers with edge inference and co-located fire-weather stations, utility- or agency-funded.Government and public safetyUrban street-flood sensor network
Open-hardware depth sensors with open data and alerts to emergency management.Government and public safetyAlerting integration with the Common Alerting Protocol and cell broadcast
Software-heavy: sensor triggers feed an alert origination tool; the alert authority keeps every decision.Government and public safetyDeployable communications and sensing for incident command
A cell on wheels with satellite backhaul, mesh telemetry and environment nodes at the incident base.05Open and enterprise
Open by default. Enterprise by contract.
The open counterpart lives on the main site for anyone to read and run. The enterprise service is designed, deployed and operated with you, under contract.
Open, on the main site
- Timing budget method
- Reference station metadata rules
Enterprise, on this site
- Timing and positioning integrity
- Reference network design and operation
- Holdover engineering
06The rest of the line
Positioning, navigation and timing, area by area.
Positioning, navigation and timingGNSS reference networks
Continuously operating stations, tied to the geodetic frame.Positioning, navigation and timingTime distribution
PTP, SyncE and NTP, engineered to the budget.Positioning, navigation and timingResilient PNT
Several sources, cross-checked, one trusted solution.Positioning, navigation and timingInterference detection
Jamming and spoofing found, located and logged.Bring us the site.
Survey, design, deployment and operation for grandmasters and holdover. The form names who receives your details.
Talk to usAsk for a quote