GRASS VALLEY IQUCP25, User Manual

Page: 86 / 338

86
Essence Processing SDC
PTP - An Overview
PTP - An Overview
PTP provides a mechanism for distributing a common reference clock throughout the
system. Each device maintains an internal clock that is synchronized to this common
reference clock. RTP timestamps within the RTP packet header (and extended header) are
used for synchronization.
Synchronization across multiple essence streams is achieved by comparing the offset
between the RTP timestamp and clock.
PTP Network
Interface
Set the check boxes to enable the network interfaces on which PTP is
supported. Enable check boxes as required.
Ethernet 1: represents the rear panel SFP1 connection.
Ethernet 2: represents the rear panel SFP2 connection.
See Connections and Cabling on page 53 for connector
information.
The Preference list allows port priority to be set. Select from:
None:
PTP will fail over from one to the next in the absence of sync
messages. Once failed over, it shall remain on that port until it fails
over again.
Ethernet 1: If Ethernet 1 is available, it has priority. Thus, if we have
failed from Ethernet 1 to Ethernet 2, as soon as Ethernet 1 becomes
available again we will switch back.
Ethernet 2: as per Ethernet 1 but for Ethernet 2.
PTP Configuration Select values from the PTP Domain and PTP Delay Request
Frequency drop-down lists, as required. Type the appropriate IP
number into the PTP Multicast address field.
PTP Status Shows the current network port used for the PTP connection and the
connection status for that port:
Free running: Card is not being synchronized.
No Lock: PTP being used but clocks haven't synchronized /-
1mS.
Locked: PTP being used and clocks are within the accepted range.
NTP:
Card is using NTP to synchronize.
Details Set the Details check box to display status information. See Interface
Status Panel on page 87, Histogram Panel on page 89, and Visible
Clocks Panel on page 90.
Save Settings Displayed only if settings on this page are changed.
Restore: discards any configuration changes made.
Restart: implements the configuration changes and reboots the card
(a reboot takes approximately 75 seconds).
Parameter Description