Network time
Maintain a consistent time reference across your infrastructure to manage, debug and protect your network.
Network time synchronises the computer clock times in your network to within a few milliseconds, ensuring that the devices connected to your IP network are adjusted to the same time. Time synchronisation is critical on a modern infrastructure network. It’s essential for ensuring staff and students don't miss meetings or lectures and for enabling your security teams to operate efficiently.
Available as part of your Janet connection, we deliver a stable time reference using the network time specified in RFC 5905. Our system provides stratum-1 time servers that are geographically distributed across the network and use various technologies to ensure accurate and consistent time references such as atomic clocks, GPS and the radio time signals MSF (UK) and DCF-77 (Europe).
Benefits
The network time protocol ensures a consistent time across your infrastructure, bringing these benefits:
- Accurate logging and auditing on devices help to reduce the time required to correlate events from multiple sources, such as firewalls, intrusion systems (IDS/IPS) and servers, which enables network security teams to respond to security events quickly and with better intelligence
- Time-based technologies such as certificates, DNSSEC and one time passcodes (OTP) become easier to maintain, even when spread over diverse logical and physical locations
- Network critical services such as clustering and systems automation require time-sensitive actions
- Network latency metrics and benchmarking are enabled
- Accurate time synchronisation is a requirement for PCI DSS compliance
- Provides digital CCTV timestamping
- Logs accurate time-based events from devices such as environmental monitors
- Our systems support both IPv4 and IPv6.
Register for the service
Contact your relationship manager to find out more about using the service. If you need support, email securityservices@jisc.ac.uk or call us on 0300 300 2212.
To register your Janet-connected organisation please complete the online application form.
Service updates
Please note that from time to time the National Physical Laboratory carries out scheduled maintenance on their MSF transmission equipment which will affect the Janet NTP servers ntp0.ja.net and ntp2.ja.net. Any known maintenance dates are provided below. There shouldn't be any interruptions to the service, but the servers ntp0 and ntp2 will be running at stratum-2 instead of stratum-1 during these maintenance periods. The remaining Janet NTP servers should be available as normal unless other maintenance work is being carried out.
Scheduled maintenance by National Physical Laboratory: 14 February 2026, 08:00 - 20:00
Additional maintenance periods: 14 February 2026: Network improvements to NTP5. 15 minute outage expected on NTP5 only. This does not affect the remaining Janet NTP servers.
Please note that from time to time the National Physical Laboratory carries out scheduled maintenance on their MSF transmission equipment which will affect the Janet NTP servers ntp0.ja.net and ntp2.ja.net. Any known maintenance dates are provided below. There shouldn't be any interruptions to the service, but the servers ntp0 and ntp2 will be running at stratum-2 instead of stratum-1 during these maintenance periods. The remaining Janet NTP servers should be available as normal unless other maintenance work is being carried out.
Scheduled maintenance by National Physical Laboratory: 14 February 2026, 08:00 - 20:00
Additional maintenance periods: 14 February 2026: Network improvements to NTP5. 15 minute outage expected on NTP5 only. This does not affect the remaining Janet NTP servers.
Support and advice
It is recommended that an organisation should choose between two to four local systems to be stratum-2 servers. The local server systems do not have to be reserved systems - they can do other work. However, they should be physically distributed around the organisation, so that they are not all on the same power supply or the same segment of a LAN.
Each local server should be configured as a client of a Janet stratum-1 server, and as a peer to the other stratum-2s at the organisation.
It is recommended that an organisation should choose between two to four local systems to be stratum-2 servers. The local server systems do not have to be reserved systems - they can do other work. However, they should be physically distributed around the organisation, so that they are not all on the same power supply or the same segment of a LAN.
Each local server should be configured as a client of a Janet stratum-1 server, and as a peer to the other stratum-2s at the organisation.
Service level description
Service description
A service to provide a high quality time reference service for use by organisations in accordance with RFC 5905.
Hours of service
The service is available 24 hours a day, seven days a week all year.
Target availability
The target availability is 100%.
Fault management
Faults with the service may be reported via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk
Resilience
The service comprises multiple servers which replicate the service.
Security
Organisations must ensure they understand and adhere to the security policy.
Your responsibilities
You are responsible for providing all relevant information requested by Jisc to enable the processing of the application.
You are also responsible on an ongoing basis for maintaining contact details.
Charges
This service is centrally-funded.
Request for service
Request this service via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk.
Service delivery time
Within five business days, as defined in SLD definitions, of receipt of all necessary information.
Terms and conditions
Organisations must ensure they understand and adhere to the Janet Network terms and conditions.
Escalation
If you are experiencing an issue with the service, and wish to escalate the issue within Jisc please contact us via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk.
Technical section
This service supports IPv4 and IPv6. See further service technical details.
Service description
A service to provide a high quality time reference service for use by organisations in accordance with RFC 5905.
Hours of service
The service is available 24 hours a day, seven days a week all year.
Target availability
The target availability is 100%.
Fault management
Faults with the service may be reported via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk
Resilience
The service comprises multiple servers which replicate the service.
Security
Organisations must ensure they understand and adhere to the security policy.
Your responsibilities
You are responsible for providing all relevant information requested by Jisc to enable the processing of the application.
You are also responsible on an ongoing basis for maintaining contact details.
Charges
This service is centrally-funded.
Request for service
Request this service via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk.
Service delivery time
Within five business days, as defined in SLD definitions, of receipt of all necessary information.
Terms and conditions
Organisations must ensure they understand and adhere to the Janet Network terms and conditions.
Escalation
If you are experiencing an issue with the service, and wish to escalate the issue within Jisc please contact us via the service desk on tel: 0300 300 2212 or via email: help@jisc.ac.uk.
Technical section
This service supports IPv4 and IPv6. See further service technical details.
ISO certification
This service is included within the scope of our ISO9001 and ISO27001 certificates.
