network protocols handbook.pdf

310Protocols GuideSS7 / C7 ProtocolProtocol NameMAP: Mobile Application PartProtocol DescriptionThe Mobile Application Part (MAP), one of the protocols in theSS7 suite, allows for the implementation of the mobile network(GSM) signaling infrastructure. The premise behind MAP isto connect the distributed switching elements, called mobileswitching centers (MSCs) with a master database called theHome Location Register (HLR). The HLR dynamically storesthe current location and profile of a mobile network subscriber.The HLR is consulted during the processing of an incoming call.Conversely, the HLR is updated as the subscriber moves aboutthe network and is thus serviced by different switches within thenetwork.MAP has been evolving as wireless networks grow, from supportingstrictly voice, to supporting packet data services as well.The fact that MAP is used to connect NexGen elements such asthe Gateway GPRS Support node (GGSN) and Serving GatewaySupport Node (SGSN) is a testament to the sound designof the GSM signaling system.MAP has several basic functions:• Mechanism for a Gateway-MSC (GMSC) to obtain arouting number for an incoming call• Mechanism for an MSC via integrated Visitor LocationRegister (VLR) to update subscriber status and routingnumber.• Subscriber CAMEL trigger data to switching elementsvia the VLR• Subscriber supplementary service profile and data toswitching elements via the VLRProtocol StructureOperation specifier8 16bitMAP ParametersLength• Length - The length of the packet.• MAP parameters - Various parameters depending onthe operation.• Operation specifier - The type of packet. The followingoperations are defined:• AuthenticationDirective• AuthenticationDirectiveForward• AuthenticationFailureReport• AuthenticationRequest• AuthenticationStatusReport• BaseStationChallenge• Blocking• BulkDeregistration• CountRequest• FacilitiesDirective• FacilitiesDirective2• FacilitiesRelease• FeatureRequest• FlashRequest• HandoffBack• HandoffBack2• HandoffMeasurementRequest• HandoffMeasurementRequest2• HandoffToThird• HandoffToThird2• InformationDirective• InformationForward• InterSystemAnswer• InterSystemPage• InterSystemPage2• InterSystemSetup• LocationRequest• MobileOnChannel• MSInactive• OriginationRequest• QualificationDirective• QualificationRequest• RandomVariableRequest• RedirectionDirective• RedirectionRequest• RegistrationCancellation• RegistrationNotification• RemoteUserInteractionDirective• ResetCircuit• RoutingRequest• SMSDeliveryBackward• SMSDeliveryForward• SMSDeliveryPointToPoint• SMSNotification• SMSRequest• TransferToNumberRequest• TrunkTest• TrunkTestDisconnect• Unblocking• UnreliableRoamerDataDirective• UnsolicitedResponseRelated protocolsSS7, ASP, BICC, BISUP, DUP, MTP, SCCP, TCAP, TUPSponsor SourceMAP is defined by ITU-T as part of SS7 protocols.Referencehttp://www.cisco.com/univercd/cc/td/doc/product/tel_pswt/vco_