Orolia Spectracom VelaSync 1232, Руководство пользователя

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Settings changed by the user will be maintained when the PTP daemon is stopped and star-
ted, and between reboots and powercycles.
Figure 2-11:
Edit PTP Settings panel
Protocol tab
PTP version : [1, 2] Select Version 1 or Version 2.
Domain : [1 through 127] Sets the current PTP Domain Number, as defined in IEEE
Std 1588-2008 Section 7.1
Communication Mode : Select multicast, hybrid, or unicast mode.
A b o u t … P T P T r a n s m i s s i o n M o d e s
The PTP Card is able to transmit the PTP packets in three transmission modes:
• Multicast Mode
: PTP packets are transmitted to all PTP Clocks by means of Mult-
icast IP addresses dedicated to the PTP protocol (224.0.1.129, 224.0.0.107). PTP packets
received by the PTP Clocks are then filtered from the Domain Number, the Port Iden-
tity (Clock Id Port Number) of the transmitter. When the Master Clock is set in
Multicast mode, this module will deny the requests from the Slaves Clocks to run in
Unicast mode. When the Master Clock is set in Unicast mode, it doesn’t transmit any
PTP messages until a Slave has been granted to run in Unicast mode.
• Unicast Mode
: This is a Point-to-Point transmission mode between two PTP
Clocks by means of the unique IP address assigned to each PTP Clock.
• Hybrid Mode
: [default] This mode uses Multicast messages for Sync, Follow-Up,
and Announce packets from the Master. Slaves are expected to send Delay Request mes-
sages to the Master in Unicast, and the Master responds in Unicast. No Unicast Nego-
tiation grants are necessary.
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VelaSync 1232 User Manual Rev. 4
2.11 Configuring PTP