Model 5600MSC Master Clock/SPG Manual
TECHNICAL DESCRIPTIONOPERATION
Revision 1.6
Page
3-67
3.7.10.5. Setting up the Internet Protocol Gateway Enable.
GENERAL
IP RULES
IP Gateway En.
IP gateway on
IP gateway off
This item is used to enable gateway operation in the 5600MSC.
When set to IP
gateway on
if an IP request comes from a source outside of
the local network, then it is returned to the gateway I.P. address.
When set to IP
gateway off
any IP requests from outside the local network
are ignored
3.7.11. Configuring the Network Time Protocol Functions (Units fitted with the T Option)
The
NTP RULES
sub-menus of the
GENERAL
Setup menu are used to configure the 5600MSC for
NTP. In most cases you will only have to plug in your Ethernet cable and configure the network IP
address (
A
) to contain an unused IP address in the valid range. Entries are made in standard IP
address format. Please consult your Network administrator for IP address allocations, netmask and
gateway requirements.
The NTP (Network Time Protocol) message generated by the 5600MSC conforms to the RFC-1305
specification which dictates that the NTP server (the 5600MSC) shall indicate an unlocked condition
when it has no reference. The 5600MSC must have its
TIME REF
menu item set to
GPS time ref
, with
a GPS antenna connected to show a GPS locked condition. (The
STATUS
display message will say
Time GPS Locked
.) The 5600MSC may also have its
TIME REF
menu item set to
Modem time ref
,
and have placed a successful call to synchronize the time within the past ten days to show a time
locked condition. (The
STATUS
display message will say
Time Locked
.) Unless the 5600MSC has
one of these two time locked conditions active, lower stratum clients will reject signals from it, according
to NTP rules.
"
This means that the 5600MSC must be locked to GPS or via modem to a high order
time reference in order to supply NTP.
3.7.11.1. Setting up the NTP restrictions.
Restrictions are a list of I.P. addresses that will be ignored if NTP requests come form them. They use
the standard I.P. address/mask. There are 8 restrictions allowed, and they are additive. For the sake
of simplicity in the manual only the menu items for restriction 1 will be shown.
3.7.11.1.1.
Setting up the NTP Restriction I.P.
GENERAL
NTP RULES
Ntp restrict 1
Restrict 1 i.p.
123.123.255.111
This item is used to set the restricted Internet Protocol address for
restriction 1. Restricted addresses are addresses that the 5600MSC will
NOT respond to.
USO
RESTRITO
