which allows for circumventing the conventional
limit of the maximum number of characters which
an SMS can contain. Our approach in this article
first uses a state of the art which extends the
fundamental concepts related to the principles and
operations of SMS service, system monitoring and
the logic of establishing a protocol of management.
Secondly, we present the description of VeSMp, our
protocol of communication. It consists of presenting
its model and architecture, and also the abstractions
which made it possible for its realisation. We end up
by showing how VeSMp is integrated into the
standards of network management like Simple
Network Management Protocol (SNMP) of
Transport Control Protocol/Internet Protocol
(TCP/IP) and Common Management Information
Protocol (CMIP) of Open System Interconnection
(OSI) (Pugolles pp 829-876, 2002).
2 STATE OF THE ART
Compared to the Internet which is seen today as the
greatest technological revolution of the century, the
success of SMS service has taken their providers by
surprise, the operators of GSM (Trosby, 2004).
2.1 Short Message Service (SMS)
The SMS offered by the GSM network appeared on
the scene for the first time in 1991 in Europe and is
defined as "a globally accepted wireless mobile
service that enables the transmission of
alphanumeric messages between mobile subscribers
and external systems such as electronic mail, paging
and voice mail systems" (NewNet SMserverTM,
1999). However, it is since the 1980s that experts in
the communities of GSM operators thought of
additional services based on text messages in their
offers in addition to those already existing, such as
voice in particular (Wikipedia, 2006).
This service of text messages of a maximum
length of 160 characters (coded using ASCII 7 bits
on 140 bytes) makes it possible for a user to carry
out, starting from his mobile terminal, the transfer of
messages to one or more recipients having GSM
mobile telephones equally or to a similar external
entity with GSM network called Shorts Message
Entity (SME) (Pons, 2001). The exchanges of short
messages (textos or SMS by abuse) are possible
thanks to the network of Signaling System n°7 (SS7)
(Trosby, 2004), (Pons, 2001). Given the differences
with other existing text services like paging, SMS
service guarantees the delivery of messages by the
network (NewNet SMserverTM, 1999), while
temporary failures are identified and short messages
are stored on the network until the recipient becomes
available. Indeed, if the latter is available, the
message is directly transmitted to him on his
terminal, if not; it is stored on a central server of
short messages SMS Center (SMSC) through which
it passes. The SMSC ensures the storage of the Short
Message (SM) in databases like Gammu
(gammu.org, 2006). Gammu is a project which
encompasses applications, scripts and drivers for
managing various functions on cellular phones and
similar devices. It also ensures the distribution of
SM to mobile terminal recipients (when these appear
in the GSM network to which they belong) in the
limit of their date of validity. The logical channels of
voice and data transmission are separated so that the
two services can simultaneously be available. As
soon as the mobile terminal is identified, the
network informs the SMSC that it can successfully
deliver the message to its recipient. The SMSC is
located by a telephone number pertaining to the
Public Mobile Land Network (PLMN). The dialogue
between the SMSC and the mobile terminal is done
through the Mobile-services Switching Center
(MSC) (Pons, 2001).
The missions initially assigned to the SMS
service are today largely exceeded. There are many
examples of operating the SMS service. Today
several Internet services are coupled with SMS.
They include: email, instant messaging, the services
of information (climatology, meteorology),
interactive banking, etc. The benefits of SMS are
today very numerous (Wikipedia, 2006), (Girondo
Stéphane), (De Wulf, 2001). Authors in reference
(NewNet SMserverTM, 1999) propose an
inexhaustive range of the most outstanding SMS
services today. We mention some here:
Reminder/calendar to point out appointments,
meetings or important events.
The reservation of places on trains, planes or
other means of transportation.
Notification services of events: (1) in the field
of network monitoring, physical and logical
safety and security, (2) announcement of
birthdays, (3) advertisements, (4) email which
informs one of the presence of an email, (5)
voice / fax which indicates the presence of a
fax or voice message. (6) …
The organization of television quiz by
broadcasters,
Communications at lower cost.
…
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