Detailed Product Description
Receive GPS satellite signals or the dual-satellite signal of GPS and GLONASS
Four 10/100M BaseT adaptive network ports
GTT-400 network time server is the ptofessional networking equipment providing high-stability time source. GTT-400 network time server receives GPS satellite signals and extracts the timing information to adjust the server's local time. It distributes standard time under NTP protocol (Network Time Protocol). Upon the PC or server which need time synchronization services, it will run a client program to read the NTP protocol, derive time information, and modify the native machine time. The network time server can be widely used in telecommunications, finance, taxation, public security and other special networks as well as general corporate networks to unify the network time.
l Receive GPS satellite signals or the dual-satellite signal of GPS and GLONASS (optional)
l Adopt RFC1119/1305 NTP protocol (Network Time Protocol) to delivery time
l Support RFC1769/2030 SNTP protocol (Simple Network Time Protocol)
l Different client programs support Windows 98/2000/NT/XP, Linux, Unix, FreeBSD and other operating systems, to adapt to different applications
l Four 10/100M BaseT adaptive network ports
l Response capability per unit time: >1000 times per second
l GPS receiving system support position holding mode which greatly improves the system availability.
l Support SNMP, with the serial port to enter
l 5 lamps display the device working status
With the rapid development of modern society, higher demand on the time precision and frequency is put on the agenda. Nowadays with the development of modern digital communication networks and the information superhighway construction, the political, cultural, technological and social information coordination is based on a strict system of time synchronization, especially in the communications, electricity, financial securities, computer networks, production line operation, administration and national defense and other fields urgently need the time synchronization equipment.
Global Positioning Satellite (GPS) signals act as the reference source of GTT-400 network time server. The time reference contained in the GPS satellite signals synchronizes with the universal time coordinated (UTC). The long-term frequency stability has achieved the10-13 level of magnitude of cesium atomic clock, which is equivalent to be only 1 second slower during 30 years. To adjust local time with this reference signal can eliminate the accumulation of deviation resulted from the low accuracy of local clock time and also can greatly improve the timing precision of the server. GTT-400 network time server use the professional GPS timing receiver. It can receive and lock the satellite signal fast and reliably.
NTP protocol (Network Time Protocol) is a common international network timing protocol. Its principle is through the client to launch a time polling to the server after an interval of time. According to a certain filtering algorithm it can calculate the time deviation between the server and the client as well as the propagation delay caused by network transmission. Then according to these two parameters to adjust the client's local time and make it consistent with the server. Compared to other time calibration prorocols, NTP protocol can eliminate the impact caused by network transmission delay, so it can provide high-precision timing services. Detailed description can be referred to the latest protocol standards documents RFC1305 and RFC2030. GTT-400 network time server can be compatible with NTP v2 / v3 / v4 in various versions.
GTT-400 network time server consists of the outdoor part and interior part.
The outdoor part is composed of the GPS satellite receiving antenna, surge arrester and antenna amplifier (optional). The function is to complete the reception of satellite signals.
The interior part is the master device of GTT-400 network time server to complete the functions of the satellite signal demodulation, the local clock calibration, achieving NTP protocol and so on. It provides NTP timing service to other network equipment by 10M network ports.