Mobile System SMS - 160 bytes that saved an industry

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Mobile SystemSMS - 160 bytes that saved an
industry

• Johan Monteliusjm_at_sics.se

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Overview

• Background
• History of SMS, functionality, usage
• Infrastructure
• SMSC, SMPP, GSM 03.40
• Message format
• 160 characters, Smart-messaging, EMS

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In short

• two-way
• terminals can both send and receive
• stor-and-forward
• delivered when terminal is activated
• short message
• 140 bytes or 160 7-bit characters
• available
• mainly GSM systems but also in other cellular
  systems

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History

• Specified in GSM phase 1 standard
• First public service in 1994
• Roaming
• Slowly introduced in 1999
• Market takes off in 1999
• 1 billion messages/month in Apr 1999
• 3 billion messages/month in Dec 1999

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Market growth
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Telia in Norway and Sweden 2001
Norway 13 of turnover
Sweden 4 of turnover
Norway 900M messages/ 1 M subs
Sweden 400M messages/ 3,2 M subs
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Usage

• Operators report an average of 10-30 user
  originated messages per month.
• Traffic
• voice message notification
• P2P messaging
• ring tones / logos
• sports scores
• other information services

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Premium SMS
Request sent as SMS message
Same request short-number (1985) regardless of
operator.
Sender of request is charged 10 NOK.
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Location based services
Request sent as SMS message
Operator dependant service
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Will SMS be replaced?
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Infrastructure

• MT
• SMS capable terminal
• SMSC
• Short message service centre
• Mobile network
• Network to deliver the SMS

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SMSC the heart of SMS
GSM Network
MSC
MSC
SMSC IWMSC/GMSC
MSC
MT
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SMSC Interface
SM-TP Short message transport protocol
HLR
GSM 0902
GSM 0411
MSC
GSM 0340
SMSC
Not standardized by ETSI
Fixed network
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the SMSC

• Vendors
• CMG, Comverse, Logica, Sema Group
• Servers
• Reliable, distributed
• 2500 messages/s
• Integrated billing support

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Everyone wants a standard
Sema
Logica
CMG
Nokia
OIS
SMPP
UCP
CIMD
www.smsforum.net
Fixed network TCP/IP X.25
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Intermediator
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SMS format

• Specified in GSM 0340 and 0911
• 140 bytes or 160 7-bit characters
• Three types of messages
• User normal text messages
• Mobile OTA configuring
• SIM operator specific applications

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Extensions to SMS

• Nokia Smart messaging
• OTA provisioning
• ring tones, logos
• EMS Enhanced Messaging Service
• 3GPP
• Ericsson, Siemens, Alcatel , Motorola
• ring tones, sound, logos, images, animations,
  text style

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EMS
EMS header
standard 7-bit characters

• Content
• Formating information, pre-defined or user
  supplied content.
• Pointers
• Where in the text flow?

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Do it yourself SMS interface

• Modem signaling using standard GSM phone