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  • 1. a.

    i. Apolicytoallowreportingtoallowtheutilitytoreadinformationfromthemeter

    ii. Apolicytoallowtheutilitytosendcommandstothemetertoshutoffpower

    iii. Apolicytoallowspecificconsumerdevicestoreadthepriceofpowerb. Theutilityhasanincentivetoonlyallowthemselvestoreadandcontrolthe

    meterduetocomplaintsfromcustomersandpossibleNERCviolation.Idon'tthinkthecustomerhasahugeincentivetoonlyallowspecificdevicestotalkthemeter.IthinkthissomethingthatneedtobemanagedbyNERC.

    c. ItseemslikeyouwouldwanttoimplementsomekindofPKIandusedthatthat.MaybeuseaTLStunneltopassinformationbetweenthemeterthecontrolcenter.Accesstothemeterisusehttpsandmaybeapassword.

    2. a. TheHMACisgoingtocomputationallylessintensive.Thismaybeimportant

    forthisapplicationwiththelowlatencyrequirements.ThedownsideistheHMACrequiresasharedsecretwhileadigitalsignaturedoesnotrequireit.

    b. Whenwemovetomorethantwodevicewereallyneedtousedigitalsignatureifwewanttobeabletodistinguishbetweeneachdevice.SincetheHMACuseasharedsecretthatwouldbesharedbetweenalldevicesandsoyoucannotuseittoauthenticatethedifferentdevices.

    3. a. AfalsenegativeiswhenthereissomethingtheIDSshouldhavedetectedthat

    itdidnot.thenegativedetectionwasfalse.IthinktheproblemhereisselfevidentbutiftheIDSisnotdetectinganissue.Itisnotdoingitjobandyounowhavesomekindofintrusioninyoursystem.

    b. AfalsepositiveiswhenthereissomethingtheIDSdetectedthatisshouldhavenotdetected.Thepositivedetectionwasfalse.TheissuehereisyounowhavetoinvestigatethepositivedetectionsandthemoreoftheseyougetthelesslikelyyouareinvestigateadetectionandthelessusefultheIDSis

    c. ThehostbasedIDSgivesyoumorevisibilityintothesystemitisinstalledonbutconversely.Youarelimitedtoonlygetinformationfromthehost.WithanetworkbasedIDS,youcangetamorecompletenetworkandbeabletoausethattodothingsyoucannotdowithahostbasedIDS.

    4. Yes,thereareafewwaysthatcrossmymindforhowtocrosstheairgap.Aninfectedthumbdriveseemslikeitwouldcrossthegameeasily.Anotherwaywouldbetohaveaninfectedlaptoppluggedintotheairgappednetwork.Maybesomeoneloadsacompromisedconfigurationontodevicepluggedintoairgappednetwork.

    5. AES6. Hashfunction,Symmetrickeycipher,Keyexchangecipher7. rootkits


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