Arbiter Systems 1088A, Руководство по эксплуатации

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C.22 Option 34: NTP/PTP Server 217
PTP Terms
•
Domain: a collection of one or more PTP subdomains. A subdomain is a logical grouping
of 1588 clocks that synchronize to each other using the PTP protocol, but that are not
necessarily synchronized to PTP clocks in another PTP subdomain. Subdomains provide
a way of implementing disjoint sets of clocks, sharing a common network, but maintaining
independent synchronization within each set.
•
Announce interval: specifies the time for sending announce messages. The range is from 0 to
4 seconds; the default is 2 seconds.
•
Sync interval: the time for sending synchronization messages. The range is from -1 to 1
seconds; the default is 1 second.
•
Delay request interval: specifies the time recommended to the member devices to send delay
request messages when the port is in the master state. The range is -1 second to 6 seconds.
The default is 5 (32 seconds).
•
Peer Delay Request: allows the requesting device to calculate the propagation delay for the
individual segment.
•
Announce receipt timeout: specifies the number of seconds the announce interval has to
pass without receipt of an Announce message before the occurrence of the event, AN-
NOUNCE RECEIPT TIMEOUT EXPIRE.
• Delay mechanism: communication delay, end to end or peer to peer.
•
Protocol: UDP IPv4, UDP IPv6 or Layer2.
•
Clock class value: used to advertise the quality level of the clock. A GPS clock is given the
value of 6.
•
Clock accuracy: 22 is used for clock accuracy to within 250 ns.
•
Priority 1: used in the execution of the best master clock algorithm.
•
Priority 2: used in the execution of the best master clock algorithm.