ATM SignalingSlide 2Signaling StandardsSignaling ChannelsMeta-SignalingATM AddressesAddressingAddressing (Cont)Slide 9NSAP is a Misnomer!Address RegistrationConnection TypesConnection SetupConnection ReleaseConnection Release (cont)Multipoint SetupMultipoint Setup (Cont)Slide 18Multipoint Conn. ReleaseMultipoint Release (Cont)Leaf Initiated Join (LIJ)Leaf Join to an Active CallLeaf Join to an Inactive CallLeaf Join to a non-LIJ CallMessage Format: Q.2931Message FormatSample Message TypesInformation Element FormatsSample Information ElementsBandwidth ContractProtocol StacksUNI 3.1 FeaturesUNI 4.0 FeaturesSummaryReferencesB-ISDN RecommendationsSlide 37Slide 38Slide 39Raj JainThe Ohio State University1ATM ATM SignalingSignalingRaj Jain Professor of Computer and Information ScienceThe Ohio State UniversityColumbus, OH [email protected]://www.cse.ohio-state.edu/~jain/Raj JainThe Ohio State University2Call Endpoints: Address FormatsCall setup/releaseTraffic Contract: Bandwidth, Quality of ServiceSignaling Mechanisms: Message formatsOverviewRaj JainThe Ohio State University3Signaling StandardsSignaling StandardsQ.931 = Basic Call Control for ISDNQ.932 = Extends/uses Q.931 for supplementary services (call forwarding, etc)Q.933 = Q.931 Extension/subset for Frame-relayDigital Subscriber Signaling System 1 (DSS1) = Call control signaling over the D channel = Q.931 + Q.932 + lower layersSignaling System 7 (SS7) deals with inside the network while DSS1 deals with outside. Q.2931 = Q.93B = Basic Call Control for B-ISDNRaj JainThe Ohio State University4Signaling ChannelsSignaling ChannelsReserved VPI/VCIx/1 = Meta-signalingx/2 = Broadcast signaling (not used initially)0/5 = ATM endpoint to local network signalingboth point-to-point and point-to-multipoint signalingx/5 = point-to-point signaling with other endpoints and other networksRaj JainThe Ohio State University5Meta-SignalingMeta-SignalingUsed to setup signaling channelsAll meta-signaling messages are one cell longand have VPI/VCI = 0/1Sets up 3 types of signaling channels:Point-to-pointGeneral broadcastSelective broadcastProcedures to:Set up new signaling channelsRelease channelsVerify channelsRaj JainThe Ohio State University6ATM AddressesATM AddressesATM Forum specifies three NSAP-like address formats: DCC ATM Format, ICD ATM Format, E.164 ATM Format. NSAP = Network Service Access PointAFIEnd SystemID (6B)High-Order DSP (10B)Selector(1B)Data CountryCode (2B)E.164 Number (8 B)39End SystemID (6B)Selector (1B)International Code Designator (2B)47End SystemID (6B)Selector (1B)45End System SuppliedNot Usedin RoutingNetwork suppliedDomain Specific Part (DSP)High-Order DSP (4B)High-Order DSP (10B)Initial Domain IdRaj JainThe Ohio State University7AddressingAddressingAuthority and Format Identifier (AFI)39 = ISO DCC, 47 = British Standards Institute ICD, 45 = ITU ISDNInitial Domain Identifier (IDI). Domain Specific Part (DSP)ISDN uses E.164 numbers (up to 15 BCD digits)ATM forum extended E.164 addresses to NSAP format. E.164 number is filled with leading zeros to make 15 digits. A F16 is padded to make 8 bytes. AFI and DSP are added.Raj JainThe Ohio State University8Addressing (Cont)Addressing (Cont)End System Identifier (ESI): 48-bit IEEE MAC address. Selector is for use inside the host and is not used for routing.All ATM addresses are 20 bytes long.ATM forum removed the division of DSP into areas, etc.Private networks must support all three formats Type of Number field = UnknownNumbering Plan Indication field = ISO NSAPRaj JainThe Ohio State University9Addressing (Cont)Addressing (Cont)Public networks must support native E.164 and may optionally support three NSAP-encoded formats. For E.164:Type of Number field = International numberNumbering Plan Indication field = Recommendation E.164If only native E.164 addresses, subaddress field in signaling messages used to convey private ATM address across.One Transit network selection possible using carrier identification code field.Raj JainThe Ohio State University10NSAP is a Misnomer!NSAP is a Misnomer!NSAP = Network Service Access Point. Identifies network layer service entrySNPA = Subnetwork point of attachment. Identifies the interface to subnetworkSNPA address (or part of it) is used to carry the packet across the network.CLNP uses NSAP to deliver the packet to the right entity in the host.ATM uses NSAP-like encoding but ATM addresses identify SNPA and not NSAP.NetworkDatalinkPhysicalSNPANSAPRaj JainThe Ohio State University11Address RegistrationAddress RegistrationUser and switch register addresses using Interim Local Management Interface (ILMI) = Simple Network Management Protocol (SNMP)User SwitchColdStart TrapInitializeGetNext RequestWhat is your address?GetNext ResponseMy address is AA-...Set RequestUse prefix +1 614-...ResponseSure. Will do.Similar activities can occur in the reverse direction.Raj JainThe Ohio State University12Connection TypesConnection TypesPermanent and SwitchedPoint to pointSymmetric or asymmetric bandwidth (Uni- or bi-directional)Point-to-multipoint: Data flow in one direction only. Data replicated by network.Leaf Initiated Join (LIJ) or non-LIJRaj JainThe Ohio State University13Connection SetupConnection SetupSetupCall ProceedingSetupCall ProceedingConnectConnect AckConnectConnect AckConnectConnect AckReleaseRelease CompleteSetupCall ProceedingAcceptRejectRaj JainThe Ohio State University14Connection ReleaseConnection ReleaseReleaseRelease completeReleaseReleaseRelease completeRelease completeReleaseRelease completeRelease completeRelease completeReleaseReleaseOrRaj JainThe Ohio State University15Connection Release (cont)Connection Release (cont)ReleaseRelease completeRelease completeReleaseConnectionTerminatedRaj JainThe Ohio State University16Multipoint SetupMultipoint SetupSetupCall ProceedingSetupCall ProceedingConnectConnect AckConnectConnect AckConnectConnect AckSetupCall Proceeding221. Connect to the first party11Raj JainThe Ohio State University17Multipoint Setup (Cont)Multipoint Setup (Cont)Add PartyAdd PartyConnectConnect AckAdd Party AckAdd Party AckSetupCallProceeding222. Add the next party. The party accepts.11Raj JainThe Ohio State University18Multipoint Setup (Cont)Multipoint Setup (Cont)Add PartyAdd PartyReleaseReleaseCompleteAdd Party RejectAdd Party RejectSetupCallProceeding223.
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