Intellinet 561099 User Manual

8‐PortGigabitWeb‐SmartSwitch
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5 VLAN
AVirtualLocalAreaNetwork(VLAN)isanetworktopologyconfiguredaccordingtoalogicalschemerather
thanthephysicallayout.VLANcanbeusedtocombineanycollectionofLANsegmentsintoan
autonomoususergroupthatappearsasasingleLAN.VLANalsologicallysegmentsthenetworkinto
differentbroadcastdomainssothatpacketsareforwardedonlybetweenportswithintheVLAN.Typically,
aVLANcorrespondstoaparticularsubnet,althoughnotnecessarily.VLANcanenhanceperformanceby
conservingbandwidth,andimprovesecuritybylimitingtraffictospecificdomains.AVLANisacollection
ofendnodesgroupedbylogicinsteadofphysicallocation.Endnodesthatfrequentlycommunicatewith
eachotherareassignedtothesameVLAN,regardlessofwheretheyarephysicallyonthenetwork.
Logically,aVLANcanbeequatedtoabroadcastdomain,becausebroadcastpacketsareforwardedtoonly
membersoftheVLANonwhichthebroadcastwasinitiated.TheIntellinet8‐PortGigabitWeb‐Smart
SwitchsupportsthreetypesofVLANs. 
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Port‐basedVLANs
Port‐basedVLANlimitstrafficthatflowsintoandoutofswitchports.Thus,alldevicesconnectedtoaport
aremembersoftheVLAN(s)theportbelongsto,whetherthereisasinglecomputerdirectlyconnectedto
aswitch,oranentiredepartment.Onport‐basedVLANs,NICsdonotneedtobeabletoidentify802.1Q
tagsinpacketheaders.NICssendandreceivenormalEthernetpackets.Ifthepacket'sdestinationlieson
thesamesegment,communicationstakeplaceusingnormalEthernetprotocols.Eventhoughthisis
alwaysthecase,whenthedestinationforapacketliesonanotherswitchport,VLANconsiderationscome
intoplaytodecideifthepacketisdroppedbytheSwitchordelivered.
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IEEE802.1QVLANs
IEEE802.1Q(tagged)VLANsareimplementedontheSwitch.802.1QVLANsrequiretagging,which
enablesthemtospantheentirenetwork(assumingallswitchesonthenetworkareIEEE802.1Q‐
compliant).VLANsallowanetworktobesegmentedinordertoreducethesizeofbroadcastdomains.All
packetsenteringaVLANwillonlybeforwardedtothestations(overIEEE802.1Qenabledswitches)that
aremembersofthatVLAN,andthisincludesbroadcast,multicastandunicastpacketsfromunknown
sources.VLANscanalsoprovidealevelofsecuritytoyournetwork.IEEE802.1QVLANswillonlydeliver
packetsbetweenstationsthataremembersoftheVLAN.Anyportcanbeconfiguredaseithertaggingor
untagging.TheuntaggingfeatureofIEEE802.1QVLANallowsVLANstoworkwithlegacyswitchesthat
don'trecognizeVLANtagsinpacketheaders.ThetaggingfeatureallowsVLANtospanmultiple802.1Q‐
compliantswitchesthroughasinglephysicalconnectionandallowsSpanningTreetobeenabledonall
portsandworknormally. 
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Somerelevantterms:
Tagging‐Theactofputting802.1QVLANinformationintotheheaderofapacket.
Untagging‐Theactofstripping802.1QVLANinformationoutofthepacketheader.

Intellinet 561099 Specifications

General

Brand	Intellinet
Model	561099
Category	Switch
Language	English