Masterclock GMR5000 - NTP Client Settings; NTP Query Modes Configuration; NTP Server and DHCP Settings

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MasterclockGMRUserManualv2–2016.12
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NTPCLIENTSETTINGS
FromtheInputControlwindow,clicktheNTPClientbuttontoaccesssettingsfortheNTPclient.
TheNTPclientisenabledbydefault.TodisabletheNTPclientforcertainapplications,deselectEnableNTPclientif
desired.
ThenetworkclientcanbeconfiguredtoeitherquerytheNTPtimeserver
ataselectedinterval,tolistentoNTP
broadcastsonly,ortolistentomulticast
broadcasts.
QUERYNTPSERVERFORTIME–isenabledby
default.Thisistheunicastmode.Thedefault
configurationistoquerytheNTPserverat10‐
secondintervals.
LISTENFORNTPVIABROADCASTADDRESS
–The
GMRcanbeconfiguredtolistentoNTPbroadcasts
byselectingtheListenforNTPviabroadcast
address[255,255,255,255]checkbox.Whenthisis
selected,thebroadcasttimeoutperiod(inseconds)
isadjustable.Toconfigurethedevicetoonlylisten
toNTPbroadcasts,clickthecheckboxListenfor
NTPbroadcasts
onlyandenteraBroadcast/
MulticastTimeoutinseconds.Thedefaulttimeout
is3600seconds(1hour).
LISTENFORNTPVIAMULTICASTADDRESS–The
GMRcanbesetuptolistentoNTPusingmulticast
addressingbyselectingtheListenforNTPvia
multicastaddresscheckbox.Whenmulticastmode
isselected,theclientwillalsolistentobroadcast
messages.
Whenenabled,theMulticastClassD/Group
Addressmaybespecifiedaswellasthefrequency
thatmulticastbroadcastswillbeissued.Thiscanbe
changedasdesired.TheNTPclientcanlistenfor
NTPmulticastbroadcastsusingthefullClassD/Group
Addressrange.TheNTPclientdoesnotrestricttheuseof
themulticastaddressassignmentandsupportsthefullrangeofClassDmulticastaddressesorgroupsfrom
224.0.0.0to239.255.255.255.
ThesegroupaddressesaredefinedandgovernedbyRFC3171,IANAIPv4MulticastGuidelines.
Typically,themulticastaddressrange224.0.1.0to
224.0.1.255isutilizedforNTPtraffic.Pleaserefertothe
RFC3171foryourspecificapplication.http://www.rfc‐editor.org/rfc/rfc3171.txt
NTPSERVERNAMES–BydefaulttheUseNTPserverprovidedbytheDHCPserverboxischeckedandaprimary
NTPserveraddressisdisplayed.Ifyouwishtounchecktheboxandprovide
yourownserveraddressesforboth
primaryandsecondaryservers,dosohere.
NTPCLIENTAUTHENTICATIONSETTINGS–Thiswindowpermitstheenteringofupto32MD5keyvaluestobe
trustedorallowed.Primaryclientsettingspermittheentryofaprimaryserverkeynumber,asecondaryserver
key
numberandabroadcastkeynumber.
NTPADVANCEDSETTINGS–Advancedsettingsallowfortheadjustmentofadditionalnetworkcommunication
settings.Undermosttypicaloperatingcircumstances,itisnotnecessary,norisitsuggested,tochangethe
advancedsettingsoptions.
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