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4.4
Operation modes / synchronization
For time synchronization, two operation modes are available, unicast or multicast.
4.4.1 Unicast
The interface is synchronized from an NTP server to UTC (coordinated world time).
This operation mode supports the monitoring and configuration of the NMI via the net-
work connection. The configuration can take place automatically through a DHCP
server or manually using the software MOBA-NMS.
For monitoring and configuration with MOBA-NMS, one of the group addresses (mul-
ticast IP) 239.192.54.0 or 239.251.34.0 for IPv4 resp. FF38::EFC0:3600 or
FF38::EFFB:2200 for IPv6 or the IP address is used.
In this operation mode, the interface will try to obtain the following network parameters
from a DHCP server (see also chapter 7.2):
-
IP
address
-
gateway
address
-
subnet
mask
-
NTP server address(es) / time zone server address
-
SNMP manager address
In this operating mode, the clock will try to obtain the following network parameters in
an IPv6 network from a DHCPv6 server (see also chapter 7.4):
-
IP
address
-
NTP server address(es) / time zone server address
-
SNMP manager address
The NTP server addresses must be configured as a DHCP option by the network ad-
ministrator. If an address is sent to the NMI, the latter will request NTP and time zone
packages from the former. The request interval can be configured using the software
MOBA-NMS.
4.4.2 Multicast
The interface is synchronized to UTC (coordinated world time) by an NTP server. The
configuration can only be carried out using the software MOBA-NMS.
For monitoring and configuration with MOBA-NMS, one of the multicast group ad-
dresses (multicast IP) is used. The group address is an IP address in the multicast
range (224.0.0.0 to 239.255.255.255), addresses selected by Moser-Baer AG from a
freely available range:
-IPv4:239.192.54.x and 239.251.34.x, whereat x = 1..15
With IPv6, the ranges mentioned above are implemented as follows:
-IPv6:FF3y::EFC0:360x and FF3y::EFFB:220x, whereat x = 0x1..0xF and y=scope
E.g.: 239.192.54.5
FF38::EFC0:3605 or 239.251.34.10
FF38::EFFB:220A
For scope, the following values are possible:2 = Link Local Scope
5
=
Site
Local
Scope
8
=
Organization
Local
Scope
14
=
Global
Scope
Contrary to unicast mode, the interface receives multicast addressed NTP and time
zone packages from an NTP server on a fixed group address (multicast IP). The
standard port numbers are 123 (NTP) and 65534 (time zone). The operation mode
multicast poses the smallest configuration effort for a network administrator.