Masterclock GMR1000 - Configuration Options; WinDiscovery; Telnet and SSH Interfaces; Password Protection and UTC Time

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MasterclockGMRUserManualv2–2016.12
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ConfigurationOptions
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WINDISCOVERY
IncludedwithyourGMRistheWinDiscoveryGUIapplication.WinDiscoveryisadetection,configurationand
managementsoftwareapplicationwhichworkswithallMasterclockbrandnetworkdevices.Itoperatesunder
mostWindows‐basedoperatingsystems.
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TELNETANDSECURESHELL(SSH)INTERFACES
Telnet,aterminal‐stylecommandlineinterface,isusedonnetworksthatarenotWindows‐based(i.e.Linuxand
UNIX).TheTelnetinterfacemaybedisabled.SecureShell(SSH)isacommandlineinterfacethatencryptsdata.
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CONFIGURATIONSAVEDVIABATTERY‐BACKEDRTC
TheGMRmaintainsitsinternaltimesettingsinbattery‐backedmemorylocatedonanRTC(RealTimeClock)chip,
whichprovidesfreewheelingaccuracy(maximumdrift)downto±165ms/day.Abuilt‐inbatterysuppliespower,
for6‐9months,totheRTCwhentheunitispoweredoff.Thisallows
theinternaltimetobemaintainedandthe
timeanddatetoincrementwheneverpowerisremoved.
Thebatteryisarechargeablemanganeselithiumtype.Abuilt‐inbatterychargingcircuitisusedwhentheunitis
normallypowered,eliminatingtheneedformaintenance.
PASSWORDPROTECTION
TheGMRisprovidedwithapasswordforsecurity.EachMasterclocknetworkdevicerequiresapasswordthat
mustbeenteredbeforethedevicewillacceptconfigurationchanges.Eachdevice,orsetofdevices,canhavea
uniquepasswordortheycanallsharethesameone.Thepasswordcanbechanged
andretainedtopermitaccess
onlytoauthorizedusers.
Apasswordcanbeamaximumof11charactersandmaycontainanysequenceofletters,numbers,andcommon
punctuation.Passwordsarecase‐sensitive.
DEFAULTPASSWORD
Thefactorydefaultpasswordis“public”
UTCTIMEREFERENCE
TheGMR’sreferencetimeisbasedonUTC(CoordinatedUniversalTime).UTCisatimestandardwhichisthebasis
fortheworldwidesystemofciviltime.Thistimescaleiskeptbytimelaboratoriesaroundtheworld,includingthe
U.S.NavalObservatory,andisdeterminedusinghighlypreciseatomicclocks.
TheUTCscaleiscoordinatedinParis
bytheInternationalBureauofWeightsandMeasures(BIPM).
UTCrunsattherateoftheatomicclocks,butwhenthedifferencebetweenthisatomictimeandonebasedonthe
Earthapproachesonesecond,aonesecondadjustment(a"leapsecond")is
madeinUTC.
UTCisthelocaltimeattheprimereferencemeridianatGreenwich,England.Atagivenlocationontheplanet,
localtimecanbedisplaced(referencedtoUTC)by‐11to+12hours.NorthandSouthAmericaarefrom‐3to‐11
hoursdelayed;mostofEuropeand
AfricaandallofAsiaandAustraliaareadvancedby+1to+12hours.Because
theNTPtimedistributionstandardoperateswithUTC‐referencetimeonly,timezoneand/ordaylightsavings
(summer)timearenotused.UTCissometimescolloquiallyreferredtoas"GreenwichMeanTime"(abbreviated
GMT).
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