Youarethesystemsengineerforyourcompany.Thenetworkconsistsofthreephysicalnetworksconnectedbyhardware-basedrouters.ThenetworkconsistsofasingleActiveDirectorydomain.AllserversrunWindowsServer2003.AllclientcomputersrunWindowsXPProfessional.

EachphysicalnetworkcontainsatleastonedomaincontrollerandatleastoneDNSserver.OnephysicalnetworkcontainsaMicrosoftInternetSecurityandAcceleration（ISA）ServerarraythatprovidesInternetaccessfortheentirecompany.Thenetworkalsocontainsacertificateserver. Companymanagementwantstoensurethatalldataisencryptedonthenetworkandthatallcomputerstransmittingdataonthenetworkareauthenticated. YoudecidetoimplementIPSeconallcomputersonthenetwork.YouedittheDefaultDomainPolicyGroupPolicyobject（GPO）toapplytheSecureServer（RequireSecurity）IPSecpolicy. Usersimmediatelyreportthattheycannotaccessresourceslocatedinremotenetworks.Youinvestigateanddiscoverthatallpacketsarebeingdroppedbytherouters.YoualsodiscoverthatActiveDirectoryreplicationisnotfunctioningbetweendomaincontrollersindifferentnetworks. Youneedtoreviseyourdesignandimplementationtoallowcomputerstocommunicateacrosstheentirenetwork.Youalsoneedtoensurethattheauthenticationkeysarestoredencrypted. Whichtwoactionsshouldyoutake？（）