Comtech EF Data CDM-625A, Installation And Operation Manual

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CDM-625A Advanced Satellite Modem MN-CDM625A
Front Panel Operation Revision 4
6–72
On the top line –
To edit the selected Time Server’s IP Address
, use the ◄ ► arrow keys to select
a digit, and then use the
▲▼
arrow keys to change that digit.
On the bottom line – this read-only field displays the time and date that the selected server was
last updated. The time displays military format (HH:MM:SS); the date displays DAY-MONTH-
YEAR format in accordance with European convention. As the example shows, this line specifies
“
Never
” if no update information exists.
6.2.1.13.4.2 CONFIG: IP

ANT

PTP (Precision Time Protocol)
Sect. K.7.3 Precision Time Protocol (PTP) (Appendix K. ETHERNET NETWORK
CONFIGURATION)
All network devices between the Grandmaster and Slave devices must support PTP
for sub-microsecond accuracy.
Precision Time Protocol (PTP) is a FAST-activated feature that synchronizes computer clocks
throughout a computer network. On LANs, PTP achieves clock accuracy in the sub-microsecond
range – much more accurate than what is attainable by NTP (Network Time Protocol) – and it is
also used in network applications where GPS is either unaffordable or inaccessible.
PTP Feature = Enabled Transport=Multicast
PTP Grandmaster = LAN
(  )
On the top line
– Use the ◄ ► arrow keys to select
PTP
or
Transport
.
For PTP – Use the
▲▼
arrow keys to select PTP as Enabled or Disabled :
•
When Enabled , PTP establishes independent Wireless Receiver/Transmitter (WRT) protocol
segments – one for LAN, and one for WAN.
• When Disabled , by default the availability of the PTP protocol depends on the near-end
(e.g., the RNC/BSC) and distant-end (e.g., the BTS) IEEE 1588v2 (PTP) capable network
devices in the network.
For Transport – Use the
▲▼
arrow keys to select Multicast or Unicast . Press ENT to continue.
CONFIG: IP

ANT

PTP: Transport=Multicast
On the bottom line – Once you select Multicast , use the ◄ ► arrow keys to navigate to PTP
Grandmaster
. Then, use the ▲▼ arrow keys to select the
PTP Grandmaster
as
LAN
or
WAN
:
•
The LAN port receives messages from the PTP master.
•
The WAN port receives messages from the PTP master.