Mobile System SMS bytes that saved an industry Johan Montelius

Overview Background –History of SMS, functionality, usage … Infrastructure –SMSC, SMPP, GSM … Message format –160 characters, Smart-messaging, EMS …

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

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

Market growth

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

Usage Operators report an average of user originated messages per month. Traffic: –voice message notification –P2P messaging –ring tones / logos –sports scores –other information services

Premium SMS Same request short- number (1985) regardless of operator. Sender of request is charged 10 NOK. Request sent as SMS message

Location based services Request sent as SMS message Operator dependant service

Will SMS be replaced?

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

SMSC – the heart of SMS SMSC IWMSC/GMSC GSM Network MT MSC

SMSC Interface MSC SM-TP Short message transport protocol GSM 03:40 GSM 04:11 GSM 09:02 HLR SMSC Fixed network Not standardized by ETSI

the SMSC Vendors –CMG, Comverse, Logica, Sema Group … Servers –Reliable, distributed –2500 messages/s –Integrated billing support

Everyone wants a standard Logica Fixed network TCP/IP X.25 SMPP UCP CIMD OIS Sema CMG Nokia

Intermediator

SMS format Specified in GSM 03:40 and 09: bytes or bit characters Three types of messages: –User: normal text messages –Mobile: OTA configuring –SIM: operator specific applications

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 …

EMS standard 7-bit characters EMS header - Content -Formating information, pre-defined or user supplied content. - Pointers -Where in the text flow?

Do it yourself SMS interface -Modem signaling using standard GSM phone