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Features of the free NTP server

NTP server ntp.mobatime.com operates in the first stratum. It retrieves the exact time directly from the global positioning system satellites. You can freely use it to synchronize your hardware and systems. The server address and time synchronization settings for different operating systems can be found on the page Connect.

Free time synchronization service is based on DTS 4130.timesever. Its features are shown in the table below.

Dimensions19" Rack, 1HE x 28TE (H x W x D [mm]) = 483 x 44 x 125
Weight approx.1.2 kg
Ambient temperature0 to 60ºC, 10-90% relative humidity, without condensation
OperationSerial interface (via RS 232) or Telnet/SSH (via LAN)
In addition, operation is also possible with SNMP.
AccuracyGPS (DCF input) to NTP server: typical < +/- 100 μs
GPS (DCF input) to DCF output: typical < +/- 10 μs
NTP to internal time typical < +/- 100 μs
Note: NTP reception (DTS 4130.timeserver as client or DTS 4130.timeserver as server to external clients) can be influenced by the network traffic load and network devices (Hub, Switch, Router, Firewall...). If many clients request simultaneously, the typical accuracy may not be reached.
Time keeping (internal)- Synchronized with GPS:
+/-10 μs to UTC
- Holdover (free run):
After at least 12 hours synchronization from the time source
< +/- 0.01 sec. / day (< 0.1ppm)
(measured over 24 h), at 20°C +/- 5°C.
< +/- 1 ms / day (< 0.01ppm)
(measured over 24 h), at constant temperature.
- After reboot without synchronization:
< +/- 0.25 sec. / day (< 2.5ppm)
(measured over 24 h), at 20°C +/- 5°C.
Redundant operation- Master to slave (optical DTS link): typical < +/- 1 μs
Time serverNTP V4 (fully V3 compatible), RFC 1305 (Port 123)
SNTP (UDP), RFC 2030 (Port 123)
TIME (TCP/UDP), RFC 868 (Port 37)
DAYTIME (TCP/UDP), RFC 867 (Port 13)
Max. number of NTP and SNTP client requests: > 250 requests / sec.
NTP ModeServer, Peer, Broadcast, Multicast
NTP-slave clock lines:1 line with up to 15 different time zone entries.
Communication through multicast:
-RFC 2236: Internet Group Management Protocol, Version 2
-RFC 1112: Host extensions for IP multicasting
-RFC 4601: Protocol Independent Multicast - Sparse Mode (PIM-SM)
-RFC 3973: Protocol Independent Multicast - Dense Mode (PIM-DM)
Time zonesUp to 80 predefined, 20 programmable entries (PC Software Tool)
Network interface10BaseT / 100BaseTX (IEEE 802.3)
Data transmission rate: Auto-negotiation / manual
Connection: RJ-45
Only shielded cables permitted.
IP ConfigurationDHCP, Static IP
Serial interfaceD-Sub 9: (38400, 8, n, 1, no flow control)
Cable length max. 3m.
DCF InputDCF77 or DCF from GPS, current loop
Time zone: MEZ or UTC (e.g. from GPS 4500)
Nominal 28 VDC, max. 32mA, response threshold 8mA
GPS InputGPS30xx as source currently not yet available
DCF OutputsDCF time code analogue DCF77, time zone selectable (same time zone for all)
Max. time deviation with GPS source: +/- 10 μs, jitter < 10 μs
- DCF time code passive current interface:
Vmax = 30 VDC, Ion = 10..15 am, Ioff < 0.1 mA @20VDC
Cable length max. 3m.
- DCF time code optical outputs:
ST plug Bayonet, (BFOC/2.5 in accordance with IEC-874-10)
Optical output powerMultimode fiber optic cable
Length = 1m, 50 / 125 μm: Pout = -15 dBm
Length = 2.5m, 62.5 / 126 μm: Pout = -11 dBm
Alarm contactOpening relay contact (Alarm active contact open).
Breaking capacity: max. 30 W (DC) or 60 VA (AC)
max. 125 VCD or 1 A / 150 VAC or 1 A
SINECSINEC Telegram via Ethernet in accordance with Siemens definition
DTS LinkPlug-in position for mini GBIC module (GigaBit Interface Converter)) 1000Mbps, 3,3V (with LC connector) e.g. D-Link DEM-311GT, SX 850 nm, 1.25 Gbps/MM/3.3 V
Maximal cable length depends on type of cable:
-Multimode fiber with a diameter of 50 μm: max. 550 m
-Multimode fiber with a diameter of 62.5 μm: max. 275 m
With LX standard longer cables can be achieved.
DC power supply24 VDC +20% / -10% / max. 10 W
Mains power supply85 – 265 VAC / 50 - 60 Hz / max. 15 VA
Power supply outputNominal 28 VDC, max. 200 mA

Synchronization requests are filtered with software specifically designed for the service. It automatically blocks DoS attacks aimed at the server and, if necessary (at greatly increased number of requests) connects additional NTP servers to process the requests (load balancing).