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MDE-LEDI-NETWORK-TDS-4099V1.0
3.4. NTP PROTOCOL GENERAL INFORMATION
NTP (Network Time Protocol) is a network protocol designed to synchronize a device (the
client) with a time reference (the server). The LEDI
®
NETWORK TDS V1 is a server that
can synchronize numerous client devices from a main time source and optionally a client
capable of synchronizing on several servers.
In client/server mode, the client queries the server who answers with a time message. The
analysis of the transit times allows to determine the time difference between the client and
the server, thus deducing the appropriate correction.
NTP Exchange
In broadcast mode, the server periodically sends a time output on the network that is
received and used by NTP clients. This mode is bandwidth saving but less accurate5 than
the Client/ Server mode since the transit times are not compensated.
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The time distribution using the NTP protocol is always done in the UTC time format.
Time zones and DST must be set up on client sides.
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The NTP protocol can be used with MD5 hashes to authenticate the timing information.
The client and the server must use the same secret key and same key index (see sec-
tion "5.2.6. “NTP” page").
Query server date
Receive reply date
client side
server side
Network
Return current server date
ENGLISH