国外无线网络设计方案

UniversityofWashingtonComputing&CommunicationsCAMPUSNETWORKDESIGN:Wiredvs.WirelessTerryGrayDirector,Networks&DistributedComputingUWComputing&CommunicationsSeptember2001UniversityofWashingtonComputing&CommunicationsScopeofUWNetworking•UWCampusNetworks–Seattle–Tacoma–Bothell/CCC•MedicalCenters(netdesign)–UWPhysiciansNetwork–UWMedicalCenter–HarborviewMedicalCenter•Pacific/NorthWestGigapop–PacificWaveexchangepoint–PacificLightRail•StatewideK20NetworkUniversityofWashingtonComputing&CommunicationsPacificNorthwestGigapopUniversityofWashingtonComputing&CommunicationsBaselineConnectivity•Shared10MbpsHD•Switched10MbpsHD•Switched10/100MbpsFD–backedbyGEswitch/routerinfrastructure•Goal:Switched10/100FDforall;GEforafew•Reality:Cat3wireplantupgradewilltakemultipleyearsandmultiplemillionsofdollarsUniversityofWashingtonComputing&CommunicationsAdvancedServices•Multicast–Partiallydeployed–Olderroutersneedtobereplaced•QoS–Laissezfaire?Premiumservice?–BestwithFDconnections.•VoIP–NeedsQoS,extra-highavailability–POEdesirable;impliesUPSinclosets•IPv6UniversityofWashingtonComputing&CommunicationsPremiumServices?•Wide-areaQoSchargeback?•PreferredaccesstoInternetforafee?•Lotsofinterestingpolicyandtechissues...UniversityofWashingtonComputing&CommunicationsMistakesWeDidn'tMake•FDDItothedesk•VLANs•ATM•Variouscut-thruIPswitchingdigressions•Claim:StayingwithpureIPandEthernethasservedUWverywell...UniversityofWashingtonComputing&CommunicationsCurrentStatistics•AvgBackbonetraffic:nearly2TB/day•PeakInboundtraffic:100Mbps(40in1999)•PeakOutboundtraffic:160Mbps(20in1999)•Doublingtime:Lessthan2years!!•Hosts:over50,000•Modems:over2,000•Switchedsubnets:70%(30%in1999)•10/100FDsubnets:25%(5%in1999)•Cat5buildings:10%UniversityofWashingtonComputing&CommunicationsUW-SBuilding/SubnetStatusDeptsDormsHospitalsTOTALBuildings193Cat3175Cat518Subnets269-41-31010Mbps85100Mbps1311000Mbps94UniversityofWashingtonComputing&CommunicationsGigEBuildings•Physics/Astronomy•FisheriesCenter•newOcean•LanderHall•McCartyHall•ParringtonHall•EdmondsonPavillion•MaryGatesHall•OUGLibrary•partofElectricalEngr.•partofHSKwing•partofHSTwing•partofJohnsonHall•partofSavery•partofThomsonHall•partof4545UniversityofWashingtonComputing&CommunicationsSimplifiedNetworkTopologyRouterRouterBorderRouterCoreSwitchEdgeSwitchEdgeSwitchInteriorSwitchInteriorSwitchGigapopInternet2DesktopDesktopInternetFedNets4303001000+BranchSite50,000PBXUniversityofWashingtonComputing&CommunicationsUniversityofWashingtonComputing&CommunicationsNumberofDevicesUniversityofWashingtonComputing&CommunicationsBackboneTrafficUniversityofWashingtonComputing&CommunicationsBorderTraffic1999UniversityofWashingtonComputing&CommunicationsBorderTraffic2001UniversityofWashingtonComputing&CommunicationsRecurringTheme:ExplosiveGrowth•Moreusers•Moredevices•Longeruse•New(bandwidth-intensive)applications–e.g.remotecollaborationtools–audio/videostreaming–tele-immersion–distancelearningUniversityofWashingtonComputing&CommunicationsNetworkingHotList•Campusbuilding/subnetupgrades•Backboneupgrades(production,experimental)•Regionalnetworking•NetworkHardening•Security•AdvancedServices•Wireless•Management/diagnostictoolsUniversityofWashingtonComputing&CommunicationsSuccessMetrics•10/100FDconnections:xx%•Multicastdeployment:xx%•QoSdeployment:xx%•Dept’lwirelesscoverage:xx%•Routercenterhardening:xx%•Backbonecapacity•IPv6capableroutersUniversityofWashingtonComputing&CommunicationsOntoWireless...UniversityofWashingtonComputing&CommunicationsWirelessCategories•WirelessbyPurpose–Point-to-Pointlinks–Accessnetworks•WirelessbySpectrum–Infrared–RF–OpticalUniversityofWashingtonComputing&CommunicationsWirelessRFbyRange•PAN/HAN(Personal/Home-Area-Network)–Bluetooth–HomeRF•LAN(Local-Area-Network)–IEEE802.11–ETSIHiperLAN2•MAN(Metro-Area-Network)–LMDS,“FixedWireless”•WAN(Wide-Area-Network)–Ricochet(R.I.P.)–CDPD–2.5G,3G,etc,etc,etcUniversityofWashingtonComputing&CommunicationsLANWirelessStandards•IEEE802.112.4GHz,1-2Mbps,FHSS,DSSS•IEEE802.11b2.4Ghz,11MbpsDSSS(WiFi)•IEEE802.11a5Ghz,54Mbps•ETSIHiperLAN25Ghz,54Mbps,TDMA•InUS,alluseunlicensed“ISM”bandsUniversityofWashingtonComputing&Communications802.11ISSUES•NetworkDesign,esp.Topology•Accesscontrol•Security•Compatibility•Interference•RelationtoBluetooth,HomeRF,etc•ObsolescenceUniversityofWashingtonComputing&CommunicationsROAMINGISSUES•Layer2(802.11)vs.Layer3(MobileIP)•Vendorincompatibility•LANvs.WAN•WewillsupportL2roamingwithinabuildingbydedicatingonesubnetforallaccesspointsinthebuilding.UniversityofWashingtonComputing&CommunicationsPolicyIssues•Partofcampusnetworkinfrastructure•Wanttoencouragesmall-scaledeploymentswithminimumoverhead,butcoordinationneededtoavoidinterference•Large-scaledeploymentsneedtobecoordinatedbyC&C•Campus-wideaccesscontrolpolicyUniversityofWashingtonComputing&CommunicationsUW-SWirelessDeployment•C&CPilotProject–KaneHall,Rm.130–MaryGatesHall–GerberdingHall–OdegaardUndergraduateLibrary•Otherwirelessprojects–CS,C&C,Business,MCIS,...UniversityofWashingtonComputing&CommunicationsPilotProjectObje