User's Manual

Chapter 3: Connections and setup
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Illustrationscontainedinthisdocumentareforrepresentationonly.
IPsecPassThroughenablesIPsectypepacketstopassbetweenWANandLAN.IPsec(IPSecurity)isa
securitymechanismusedinVirtualPrivateNetworks(VPNs).
PPTPPassThroughenablesPPTPtypepacketstopassbetweenWANandLAN.PPTP(PointtoPoint
TunnelingProtocol)isanothermechanismsometimesusedinVPNs.
RemoteConfigManagementmakestheconfigurationwebpagesinyourgatewayaccessiblefromthe
WANside.Notethatpageaccessislimitedtoonlythosewhoknowthegatewayaccesspassword.When
accessingyourgatewayfromaremotelocation,yourmustuseHTTPport8080andtheWANIPaddress
ofthegateway.e.g.,iftheWANIPaddressis157.254.5.7,youwouldnavigateto
http://157.254.5.7:8080toreachyourgateway.
MulticastEnableenablesmulticasttraffictopassthroughWANandLAN.Youmayneedtoenablethis
toseesometypesofbroadcaststreamingandcontentontheInternet.
UPnPUniversalPlugandPlay(UPnP)helpsdevices,suchasInternetappliancesandcomputers,access
thenetworkandconnecttootherdevicesasneeded.UPnPdevicescanautomaticallydiscoverthe
servicesfromotherregisteredUPnPdevicesonthenetwork.
NATALGenableNATALG(applicationlayergateways)allowscustomizedNATtraversalfilterstobe
pluggedintothegatewaytosupportaddressandporttranslationforcertainapplicationlayer
"control/data"protocolssuchasRSVP,FTP,TFTP,Kerb88,NetBios,IKE,RTSP,Kerb1293,H225,PPTP,
MSN,SIP,ICQ,IRC666x,ICQTalk,Net2Phone,IRC7000,IRC8000filetransferinIMapplicationsetc.In
orderfortheseprotocolstoworkthroughNATorafirewall,eithertheapplicationhastoknowaboutan
address/portnumbercombinationthatallowsincomingpackets,ortheNAThastomonitorthecontrol
trafficandopenupportmappings(firewallpinhole)dynamicallyasrequired.Legitimateapplicationdata
canthusbepassedthroughthesecuritychecksofthefirewallorNATthatwouldhaveotherwise
restrictedthetrafficfornotmeetingitslimitedfiltercriteria.