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The Short Message Service is realised by the use of the Mobile Application Part (MAP) of the SS#7 protocol, with Short Message protocol elements being transported across the network as fields within the MAP messages.〔Mobile Application Part specification, 3GPP TS 29.002, available (here )〕 These MAP messages may be transported using 'traditional' TDM based signalling, or over IP using SIGTRAN and an appropriate adaptation layer. The Short Message protocol itself is defined by (3GPP TS 23.040 ) for the ''Short Message Service - Point to Point (SMS-PP)'',〔SMS Point to Point specification, 3GPP TS 23.040, available (here )〕 and (3GPP TS 23.041 ) for the ''Cell Broadcast Service (CBS)''.〔Cell Broadcast Service specification 3GPP TS 23.041, available (here )〕 Four MAP procedures are defined for the control of the Short Message Service:〔 * Mobile Originated (MO) short message service transfer; * Mobile Terminated (MT) short message service transfer; * Short message alert procedure; * Short message waiting data set procedure. ==MO short message Service transfer== The diagram to the right depicts a simplified call flow for a successful submission of a mobile originated short message.〔 When the subscriber sends a short message, the handset sends the text message over the air interface to the MSC/SGSN. Along with the actual text of the short message, the destination address of the SM and the address of the Short Message Service Centre (SMSC) are included, the latter taken from the handset's configuration stored on the SIM card.〔Point-to-Point (PP) Short Message Service (SMS) support on mobile radio interface specification,3GPP TS 24.011, available (here )〕 Regardless of the air interface technology, the VMSC/SGSN invokes the MAP service package MAP_MO_FORWARD_SHORT_MESSAGE to send the text to the Interworking MSC of the Service Centre whose address was provided by the handset. This service sends the mo-ForwardSM MAP operation to the SMSC identified in the SM Submission from the handset, embedded within a Transaction Capabilities Application Part (TCAP) message, and transported over the core network using the Signalling Connection Control Part (SCCP).〔 The Interworking MSC of the SMSC, on receipt of the MAP mo-ForwardSM message, passes the SMS-PP〔 Application Protocol Data Unit (APDU) containing the text message to the actual Service Centre (SC) of the SMSC for storing, and subsequent 'forwarding' (delivery) to the destination address and the SC returns an acknowledgement indicating success or failure. On receipt of this submission status from the Service Centre, the Interworking MSC will send an appropriate indication back to the VMSC/SGSN of the sending subscriber. The message submission status is then forwarded, over the air interface, to the subscriber's handset.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Short message service technical realisation (GSM)」の詳細全文を読む スポンサード リンク
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