An Independent Source of Precise Time for Your Network
The CESTime service, operated by the CESNET association, delivers precise time to organizations over a separate network that is physically isolated from the Internet. Customers gain an additional independent time source for their internal time authority (Grandmaster Clock) – and with it greater resilience of time synchronization, including for critical systems. Every connection to the CESTime service begins with an individual consultation.
What Do I Need to Connect to the CESTime Service?
To connect, you need a working infrastructure for distributing time within your own network – you will use the CESTime service as an additional time source alongside your existing ones.
Specifically, we assume that you:
- operate an internal time authority (Grandmaster Clock) that distributes time within your network, for example using PTP or NTP,
- receive a time signal from at least one source (GNSS, NTP or DCF77),
- have a device capable of comparing the time from individual inputs.
If critical systems in your organization depend on precise time, we recommend ensuring time continuity even in the event of an outage or interference on any of the time distribution paths.
Which Types of Physical Connection Does the CESTime Service Support?
The preferred method is a fiber optic connection; a copper connection is only possible in exceptional cases and with reduced accuracy.
Available physical connection options:
- Dedicated optical fiber – a fiber reserved exclusively for the CESTime service,
- Dedicated wavelength – a wavelength separated by optical filters and/or wavelength division multiplexers (WDM),
- Copper cable – only in exceptional cases, with reduced time distribution accuracy.
The CESTime service cannot be operated over a shared internet connection – the CESTime network is separated from the Internet. However, several mutually independent channels can be operated within a single physical optical fiber. The CESTime team will help the customer with the technical implementation, including the design and, if needed, the supply of equipment.
Which Protocols Does the CESTime Service Use to Deliver Time?
The CESTime network delivers precise time using the PTP (IEEE 1588) and White Rabbit protocols. The CESTime service does not support NTP.
- The customer's Grandmaster Clock is connected directly to the CESTime network.
- The infrastructure does not carry any data other than time protocols between ports.
- The commercial terms are the same for both PTP and White Rabbit.
Why Does Every Connection to CESTime Begin with an Individual Consultation?
Every organization has different technical prerequisites as well as different requirements for the accuracy and resilience of time synchronization. That is why a personal consultation always takes place before the CESTime service is provided. Together, we assess your organization's infrastructure, propose a suitable form of connection and set up the service parameters so that CESTime brings you the greatest possible benefit.
How Do I Order the CESTime Service?
The fastest first step is to send an e-mail to cestime@cesnet.cz
Based on your inquiry, we will arrange an initial consultation and propose a solution tailored to your organization's needs.