GSM Short Message Service

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GSM Short Message Service
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GSM Short Message Service

• Can contain up to 140 octets, or 160 char.
• To allow messages longer than 160 char.
• SMS concatenation
• SMS compression
• SDCCH signaling channel
• Two type of GSM SMS
• Cell broadcast service
• Point-to-point service

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12.1 SMS Architecture
Figure 12.1 GSM short message service network
architecture
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12.2 SMS Protocol Hierarchy
Figure 12.2 SMS MS-MSC protocol hierarchy (mobile
origination)
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12.2 SMS Protocol Hierarchy

• 12.2.1 Short Message Transfer Layer
• Provides services to transfer SM-AL short msg.
• Generate a reference number SMI (short message
  identifier)
• SM-AL SMI is not carried between the MS and SM-SC
• Four types of transfer protocol data units
  (TPDUs)
• SMS-SUBMIT
• SMS-DELIVER
• SMS-STATUS-REPORT
• SMS-COMMAND

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12.2 SMS Protocol Hierarchy

• 12.2.2 Short Message Relay Layer
• Provides services to transfer TPDUs and delivery
  reports for SM-TL
• Generate SM-RL SMI for every short message
• SM-RL SMI is mapped to and from SM-TL SMI
• SM-RL SMI at the MS is not carried at the peer
  entity in the SM-SC
• SM-RP consists of the following RPDU types
• RP-DATA
• RP-SM-MEMORY-AVAILABLE
• RP-ACK
• RP-ERROR

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12.2 SMS Protocol Hierarchy

• 12.2.3 Connection Management Sublayer
• Provides services to support the SM-RL
• MS has two SMC entities
• MS-originated (MO) short message service
• MS-terminated (MT) short message service
• SM-CP consists of following protocol elements
• CP-DATA
• CP-ACK
• CP-ERROR
• MNSMS-ESTablish
• To establish an MM-connection and transfer RPDU
  on that establish
• MNSMS-DATA
• Transfer an RPDU on MM-connection
• MNSMS-RELease
• MNSMS-ABORT
• MNSMS-ERROR

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12.3 Mobile-Originated Messaging

• The logical message path is
• MS -gt originating MSC -gt IWMSC -gt SM-SC

Figure 12.3 Mobile-originated short messaging
(part 1)
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12.3 Mobile-Originated Messaging
Figure 12.4 MM-connection establish for
mobile-originated short messaging
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12.3 Mobile-Originated Messaging
Figure 12.5 Mobile-originated short messaging
(part 2)
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12.3 Mobile-Originated Messaging
Figure 12.6 Mobile-originated short messaging
(part 3)
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12.4 Mobile-Terminated Messaging

• The logical massage path is
• SM-SC -gt GMSC -gt terminating MSC -gt MS

Figure 12.7 Mobile-terminated short messaging
(part 1)
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12.4 Mobile-Terminated Messaging
Figure 12.8 Mobile-terminated short messaging
(part2)
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12.4 Mobile-Terminated Messaging
Figure 12.9 Mobile-terminated short messaging
(part 3)