Model: MC-1-DE
Doc Ref. No:-m05dom102
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User’s Manual
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intervals or NTP packets may be discarded by network (as NTP packet is UDP based transmission
packet) since it may cross packet TTL (Time To Live) value in network.
9.6 NTP Hierarchical Time Distribution:
NTP architecture model consists of number of primary reference sources, synchronized by wire or ra-
dio clock. There are other several multiple secondary time sources/clients which are arranged in hie-
rarchal manner in network which request time from primary reference sources. Under normal cir-
cumstances it is intended that the synchronization subnet of primary and secondary servers assumes
a hierarchical-master-slave configuration with the primary servers at the root and secondary servers
of decreasing accuracy at successive levels toward the leaves.
NTP Server-client architecture are generally arranged in hierarchical arrangement in network. Refer
below figure 27 to understand time distribution model in hierarchical arrangement.
Figure 27 NTP Time distributions in Hierarchical Arrangement
As shown in Figure 27, GPS TIME SYNC UNIT MC-1-DE receives time form GPS Satellites. Accord-
ing to NTP protocol, GPS satellites are considered to be operating at stratum level 0 as most accu-
rate time source. As the devices passes down to other levels of network architecture, stratum level
increases by 1. GPS TIME SYNC UNIT MC-1-DE model operates at stratum level 1 which is consi-
dered next accurate time source to GPS Satellites. Other NTP clients stratum level increases by 1 as
NTP devices goes downwards in network layers. Stratum level can be upto maximum 14 to be consi-
dered as valid NTP time source.
NTP client accuracy also depends on the hierarchical arrangement of NTP servers and NTP clients in
network because the stratum value increases by 1 at every hierarchical stage in network and as stra-
