GPS / GNSS / NavIC Time Servers
Primary Reference Clock

VCL-2156-EXT NTP Server is a dual-band GPS clock supporting L1 (GPS, GNSS, SBAS, Galileo) and L5 (GPS, Galileo E5a, BeiDou B2a, NavIC) signals. Its dual-frequency design ensures high accuracy, reliability, and resilience. Multipath Mitigation with Dynamic Satellite Selection maintains signal integrity in difficult conditions. Ideal for telecom, power grids, data centres, and defence, it provides precise, uninterrupted synchronization with stable outputs from multiple constellations.

Using two frequency L1 and L5 bands makes the clock less vulnerable to jamming or spoofing of a single frequency. The receiver can switch to the other frequency band in case one is compromised by such attacks. Provides better continuity of service for critical infrastructure. VCL-2156-EXT locks to a GPS / GNSS / NavIC reference to provide an NTP time reference on up to 4+1, 10/100BaseT Ethernet Ports which can be segregated to serve separate classes of assets in the network.

NTP Peering:

NTP peering is a method to allow multiple NTP servers to share time. Having more than one reference server configured increase's reliability of the NTP server. In peering mode, in addition to its GPS reference, VCL-2156-EXT can be configured to receive and monitor time from an additional Stratum 1 NTP Server available on the network. This allows the unit to fall back to its peer source in the event its primary reference becomes unavailable.

Performance:

The VCL-2156-EXT has 4+1, 10/100 BaseT Industrial Ethernet Ports that meet and comply with “Power Contact and Lightening Protection” as per EN61000-4-5 Level 3 specifications making it suitable for the equipment to be installed in harsh industrial environments which include Electric Sub-Stations, Railway and Metro Networks. VCL-2156-EXT provides a better than 30 nanosecond accuracy to assure high bandwidth NTP Performance of better than 7,500 NTP requests per second (40,000 NTP Slaves supported).

Security Features and Capabilities:

• MD5/SHA1 authentication for secured NTP access
• Key management for NTP clients
• Option to disable clear text (Telnet) for secure communication
• Supports Secure Shell (SSH) network protocol for encrypted communication
• Supports RADIUS server for secure authentication and access control
• Supports user-configurable Ethernet port protection
• Supports NTP Peering for creating a redundant NTP server
• Encrypted Password Control to access the device
• Password Strength Monitoring
• Alert notifications using secure SNMPv3 traps

Holdover (G.812) Synchronization:

• OCXO (Double Oven-Controlled Crystal Oscillator)
• OCXO Stability: ± 3ppb
• Accuracy
• One day Aging is ± 0.4ppb
• 20Year Aging is ± 80ppb