mplaylist.Formoreinformation,seeCreatingmulticaststationswithWindowsMediaAdministrator.
IfyouusetheConfigureandPublishMulticastBroadcastStreamsQuickStartwizardontheMulticastStationspageinWindowsMediaAdministratortocreateastation,streamformatinformationisaddedtothestationdefinitionontheSpecifystreamformatinformationscreen.
Ifyouareusingtheadvancedmethodtocreateastationorifyouareaddingstreamstoanexistingstation,youmustaddstreamformatinformationtothestationdefinition.Formoreinformation,seeEditingstationproperties.
Creatingunicastrolloverforamulticaststation
UnicastrollovercanbeusedwhenMicrosoftWindowsMediaPlayercannotreceivemulticastpacketsfromastation.Thiscanoccur,forexample,becausethenetworkroutersarenotmulticast-enabled,orbecauseWindowsMediaPlayerisbeyondthetime-to-live(TTL)radiusofthemulticast.Unicastrolloverwillnotoccurwhenamulticaststationstreamsnocontentbecauseamulticaststationemitsbeaconpacketsevenifnoprogramisdefinedforit.IfWindowsMediaPlayeriswithintheTTLradiusofthemulticast,itbindstothebeaconpackets,whichcontainnocontent.
WhenMicrosoftWindowsMediaPlayeropensan.asxfileforamulticaststation,the.asxfileinstructsWindowsMediaPlayertodownloadthe.nscfile,whichcancontainaunicastrolloverURL.IfWindowsMediaPlayercannotreceivetheASFstreamthatisbeingmulticast,itusestheunicastrolloverURLtoconnecttotheserverandreceivethestreamfromabroadcastunicastpublishingpoint.
IfyouuseConfigureandPublishMulticastBroadcastStreamsQuickStartwizardtocreateastationformulticastanddistribution,thewizardcreatesabroadcastunicastpublishingpoint(withanaliasthatisidenticaltothestationname)thatreferencesthestation.ThewizardaddsaunicastrolloverURLtothisbroadcastunicastpublishingpointinthestationdefinition.
Ifyouusethewizardtocreateamulticaststation,orifyouusetheadvancedmethodtocreateastationformulticastanddistributionoramulticaststation,andyouwanttoenableunicastrolloverforyourstation,youmustcreateabroadcastunicastpublishingpointthatusesthemulticaststationasthestreamsource.Formoreinformation,seeUsingbroadcastunicastpublishingpoints.Thentoenableunicastrolloverforthestation,youmustsupplyaunicastURLtothebroadcastunicastpublishingpointintheformmms://server_name/alias,whereserver_nameisthenameoftheserverthathoststhebroadcastunicastpublishingpointandaliasisthebroadcastunicastpublishingpointalias.Formoreinformation,seeEditingstationproperties.
Publishingstationcontent
Whenyouchooseapublishingmethod,thewizardcreatesthat.htmfileorcopiesthatHTMLcodetotheMicrosoftWindowsclipboard,sothatyoucanpastethecodeintoanHTMLpage.An.asxfilethatpointstotheASFstreamiscreatedbydefault;thefollowingpublishingmethodsprovidetheWebsyntaxthatlinkstothe.asxfile.
Createan.htmfilewithan
tothe.asxfile
StationQuickStartwizardpromptsyouforalocationinwhichtosavethe.htmfile,andtorenameitifnecessary.Tomakethisfileavailabletoothers,saveitonaWebserver.Thedefaultnameofthe.htmfileisstation_name_href_tag.htm.
TotesttheWebpagecreatedbythisfile,clickTest.htmw/HREFonthelastscreenofthewizardtoopenthesampleWebpage,whichcontainsthelinktothe.asxfile.ClickthelinktoopenMicrosoftWindowsMediaPlayer.WindowsMediaPlayeraccessesthestationandplaysthestream.
Createan.htmfilecontainingandtagsforWindowsMediaPlayer
StationQuickStartwizardpromptsyouforalocationinwhichtosavethe.htmfile,andtorenameitifnecessary.Tomakethisfileavailabletoothers,saveitonaWebserver.Thedefaultnameofthe.htmfileisstation_name_object_tag.
TotesttheWebpagecreatedbythisfile,clickTest.htmw/OBJECTonthelastscreenofthewizardtoopentheWebpageinthebrowser.WhentheWebpageopens,theWindowsMediaPlayercontrolappears.WindowsMediaPlayerautomaticallyaccessesthestationandplaysthestream.
CopysyntaxtotheWindowsclipboard
Thisoptioninsertsthenameofandpathtoyour.asxfileinthecodethatcreatesalinktoyourstationcontent.PastethisHTMLcodefromWindowsclipboardintoanyWebpagetocreatealinktoyourstation.
CopyandsyntaxtotheWindowsclipboard
Thisoptioninsertsthenameofthe.asxfileandthepathtothe.asxfileintothecodethatembedstheWindowsMediaPlayercontrol.PastethisHTMLcodefromtheWindowsclipboardintoanyWebpagesothatyourstationcontentisplayedautomaticallywhentheWebpageisopened.
Editingstationproperties
TheNewStationpageletsyouenterindividualstationpropertiestocreateastationwithoutusingStationQuickStartwizard.TheEditStationpageletsyouviewandeditthepropertiesofanexistingstation.Thesetwopagesareidentical,exceptthatthepropertyboxesintheNewStationpageareempty.
Thestationpropertiesaredescribedinthefollowingtable.TheName,Port,andStationFilePathpropertiesarerequired;youcannotcreatean.nscfilewithoutfillingintheseboxes.Theotherpropertiesareoptional.
SettingmulticastdestinationIPaddressandport
AmulticastprogramisdirectedtoitsdestinationbythestationIPaddressandport.ClientsreceivethemulticastprogrambyinstructingtheirnetworkcardstolistenforpacketsarrivingatthatIPaddressandport.
ForASFcontent,thedestinationIPaddressandportaresetwhenyoucreatethestationinWindowsMediaAdministratorusingtheStationspage.Clientslearnwhichaddressandporttolistentobydownloadingthe.nscfile.
YoucancreatemultipleprogramsdestinedforthesameIPaddress;however,youmustavoidmulticastingprogramstothesameIPaddresssimultaneously.Forexample,sendingafiletothesamedestinationasanaudiomulticastcaninterferewiththeaudiostream.
Note
Forfiletransferstreams,thedestinationIPaddressandportaresetforeachstreaminaprogramwhenyouaddstreamsusingtheMulticastFileTransferspageinWindowsMediaAdministrator.Inorderforaclienttoreceivethemulticasts,theIPaddressandportyousetforthefiletransferstreammustmatchtheIPaddressandportspecifiedbytheclientnetworkcard.Formoreinformation,seeConfiguringamulticastfiletransfer.
Settingmulticastscope
YoucanlimitthereachofamulticasttotheimmediatesubnetworkorexpandthescopetotheentireInternet.Thescopeissetbyspecifyingatime-to-live.Thisvalue,sometimescalledthenumberofhops,decreaseseachtimethemulticastpassesthroughanetworkrouter.Whenthevaluereaches1,therouterstopsforwardi
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