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SMS Tutorial
Definition & Overview
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Definition |
| Short message service (SMS)
is a globally accepted wireless service that
enables the transmission of alphanumeric
messages between mobile subscribers and
external systems such as electronic mail,
paging, and voice-mail systems. |
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Overview |
| This tutorial provides
an introduction to basic SMS concepts,
specifications, networks, and services. |
Introduction
| SMS appeared on the
wireless scene in 1991 in Europe. The
European standard for digital wireless, now
known as the Global System for Mobile
Communications (GSM), included short
messaging services from the outset. |
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| In North America, SMS
was made available initially on digital
wireless networks built by early pioneers
such as BellSouth Mobility, PrimeCo, and
Nextel, among others. These digital wireless
networks are based on GSM, code division
multiple access (CDMA), and time division
multiple access (TDMA) standards. |
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| Network consolidation
from mergers and acquisitions has resulted
in large wireless networks having nationwide
or international coverage and sometimes
supporting more than one wireless
technology. This new class of service
providers demands network-grade products
that can easily provide a uniform solution,
enable ease of operation and administration,
and accommodate existing subscriber
capacity, message throughput, future growth,
and services reliably. Short messaging
service center (SMSC) solutions based on an
intelligent network (IN) approach are well
suited to satisfy these requirements, while
adding all the benefits of IN
implementations. |
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| Figure 1 represents the
basic network architecture for an IS–41 SMSC
deployment handling multiple input sources,
including a voice-mail system (VMS),
Web-based messaging, e-mail integration, and
other external short message entities (ESMEs).
Communication with the wireless network
elements such as the home location register
(HLR) and mobile switching center (MSC) is
achieved through the signal transfer point (STP). |
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Picture 1. Basic
Network Architecture for an SMS Deployment
(IS-41) |
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| SMS provides a
mechanism for transmitting short messages to
and from wireless devices. The service makes
use of an SMSC, which acts as a
store-and-forward system for short messages.
The wireless network provides the mechanisms
required to find the destination station(s)
and transports short messages between the
SMSCs and wireless stations. In contrast to
other existing text-message transmission
services such as alphanumeric paging, the
service elements are designed to provide
guaranteed delivery of text messages to the
destination. Additionally, SMS supports
several input mechanisms that allow
interconnection with different message
sources and destinations. |
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| A distinguishing
characteristic of the service is that an
active mobile handset is able to receive or
submit a short message at any time,
independent of whether a voice or data call
is in progress (in some implementations,
this may depend on the MSC or SMSC
capabilities). SMS also guarantees delivery
of the short message by the network.
Temporary failures due to unavailable
receiving stations are identified, and the
short message is stored in the SMSC until
the destination device becomes available. |
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| SMS is characterized by
out-of-band packet delivery and
low-bandwidth message transfer, which
results in a highly efficient means for
transmitting short bursts of data. Initial
applications of SMS focused on eliminating
alphanumeric pagers by permitting two-way
general-purpose messaging and notification
services, primarily for voice mail. As
technology and networks evolved, a variety
of services have been introduced, including
e-mail, fax, and paging integration,
interactive banking, information services
such as stock quotes, and integration with
Internet-based applications. Wireless data
applications include downloading of
subscriber identity module (SIM) cards for
activation, debit, profile-editing purposes,
wireless points of sale (POSs), and other
field-service applications such as automatic
meter reading, remote sensing, and
location-based services. Additionally,
integration with the Internet spurred the
development of Web-based messaging and other
interactive applications such as instant
messaging, gaming, and chatting. |
Benefits of SMS
| In today's competitive
world, differentiation is a significant
factor in the success of the service
provider. Once the basic services, such as
voice telephony, are deployed, SMS provides
a powerful vehicle for service
differentiation. If the market allows for
it, SMS can also represent an additional
source of revenue for the service provider. |
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| The benefits of SMS to
subscribers center around convenience,
flexibility, and seamless integration of
messaging services and data access. From
this perspective, the primary benefit is the
ability to use the handset as an extension
of the computer. SMS also eliminates the
need for separate devices for messaging
because services can be integrated into a
single wireless device—the mobile terminal.
These benefits normally depend on the
applications that the service provider
offers. At a minimum, SMS benefits include
the following: |
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Delivery of notifications and alert |
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Guaranteed message deliver |
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Reliable, low-cost communication
mechanism for concise information |
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Ability
to screen messages and return calls in a
selective way |
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Increased subscriber productivity |
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| More sophisticated
functionality provides the following
enhanced subscriber benefits: |
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Delivery of messages to multiple
subscribers at a time |
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Ability
to receive diverse information |
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E-mail
generation |
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Creation of user groups |
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Integration with other data and
Internet-based applications |
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| The benefits of SMS to
the service provider are as follows |
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Ability
to increment average revenue per user
(due to increased number of |
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calls
on wireless and wireline networks by
leveraging the notification capabilities
of SMS) |
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An
alternative to alphanumeric paging
services, which may replace or |
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complement an existing paging offer |
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Ability
to enable wireless data access for
corporate users |
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New
revenue streams resulting from addition
of value-added services such |
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as
e-mail, voice mail, fax, and Web-based
application integration, reminder
service, stock and currency quotes, and
airline schedules |
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Provision of key administrative services
such as advice of charge, over-the- |
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air
downloading, and over-the-air service
provisioning |
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Protection of important network
resources (such as voice channels), due
to |
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SMS’
sparing use of the control and traffic
channels |
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Notification mechanisms for newer
services such as those utilizing
wireless |
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application protocol (WAP) |
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| All of these benefits
are attainable quickly, with modest
incremental cost and short payback periods,
which make SMS an attractive investment for
service providers. |
Network Elements &
Architecture
| The basic network
structure of SMS in an IS-41 network is
depicted in Picture 1. |
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External Short
Messaging Entities |
| An ESME is a device
that may receive or send short messages. The
short message entity (SME) may be located in
the fixed network, a mobile device, or
another service center. |
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VMS
- The VMS is responsible for receiving,
storing, and playing voice |
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messages intended for a subscriber that
was busy or not available to take a
voice call. It is also responsible for
sending voice-mail notifications for
those subscribers to the SMSC. |
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Web
- The growth of the Internet has also
affected the world of SMS. |
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Therefore, it is almost mandatory to
support interconnections to the World
Wide Web for the submission of messages
and notifications. The increasing number
of Internet users has a positive impact
on the SMS traffic increment experienced
in the last few years. |
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E-Mail - Probably the most demanded
application of SMS is the ability to |
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deliver
e-mail notifications and to support
two-way e-mail, using an SMS-compliant
terminal. The SMSC must support
interconnection to e-mail servers acting
as message input/output mechanisms. |
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Others - There are several other
mechanisms to submit short messages to |
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the
SMSC that include, but are not limited
to, paging networks, specialized
software for PC-based messaging and
operator bureaus. |
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SMSC |
| SMSC is a combination
of hardware and software responsible for the
relaying and storing and forwarding of a
short message between an SME and mobile
device. |
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| The SMSC must have high
reliability, subscriber capacity, and
message throughput. In addition, the system
should be easily scalable to accommodate
growing demand for SMS in the network. |
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| Normally, an IN-based
solution will allow for a lower entry cost
compared to point solutions because it can
support other applications on a single
hardware platform and share resources,
thereby spreading the deployment cost over
several services and applications. |
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| Another factor to be
considered is the ease of operation and
maintenance of the application, as well as
the flexibility to activate new services and
upgrade to new software releases. |
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| The benefits of SMS to
the service provider are as follows |
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|
|
|
Ability
to increment average revenue per user
(due to increased number of |
| |
calls
on wireless and wireline networks by
leveraging the notification capabilities
of SMS) |
|
|
An
alternative to alphanumeric paging
services, which may replace or |
| |
complement an existing paging offer |
|
|
Ability
to enable wireless data access for
corporate users |
|
|
New
revenue streams resulting from addition
of value-added services such |
| |
as
e-mail, voice mail, fax, and Web-based
application integration, reminder
service, stock and currency quotes, and
airline schedules |
|
|
Provision of key administrative services
such as advice of charge, over-the- |
| |
air
downloading, and over-the-air service
provisioning |
|
|
Protection of important network
resources (such as voice channels), due
to |
| |
SMS’
sparing use of the control and traffic
channels |
|
|
Notification mechanisms for newer
services such as those utilizing
wireless |
| |
application protocol (WAP) |
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Signal Transfer Point |
| The STP is a network
element normally available on IN deployments
that allows IS-41 interconnections over
signaling system 7 (SS7) links with multiple
network elements. |
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HLR |
| The HLR is a database
used for permanent storage and management of
subscriptions and service profiles. Upon
interrogation by the SMSC, the HLR provides
the routing information for the indicated
subscriber. Also, if the destination station
was not available when the message delivery
was attempted, the HLR informs the SMSC that
the station is now recognized by the mobile
network to be accessible, and thus the
message can be delivered. |
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Visitor Location
Register (VLR) |
| The visitor location
register is a database that contains
temporary information about subscribers
homed in one HLR who are roaming into
another HLR. This information is needed by
the MSC to service visiting subscribers. |
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MSC |
| The MSC performs the
switching functions of the system and
controls calls to and from other telephone
and data systems. The MSC will deliver the
short message to the specific mobile
subscriber through the proper base station. |
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Air Inteface |
| The air interface is
defined in each one of the different
wireless technologies (GSM, TDMA, and CDMA).
These standards specify how the voice or
data signals are transferred from the MSC to
the handset and back, as well as the
utilization of transmission frequencies,
considering the available bandwidth and the
system’s capacity constraints. |
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The Base Station
System |
| All functions related
to the transmission of electromagnetic radio
signals between the MSC and the mobile
devices are performed in the base station
(BS). The BS consists of base station
controllers (BSCs) and the base transceiver
stations (BTSs), also known as cell sites or
simply “cells.” The BSC may control one or
more BTSs and is in charge of the proper
resource assignment when a subscriber moves
from one sector of one BTS to another,
regardless of whether the next sector lies
within the same BTS or in a different one. |
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The Mobile Device |
| The mobile device is
the wireless terminal capable of receiving
and originating short messages. Commonly,
these devices have been digital cellular
phones, but more recently the application of
SMS has been extended to other terminals
such as POS, handheld computers, and
personal digital assistants (PDAs). The
wireless network signaling infrastructure is
based on SS7. SMS makes use of the mobile
application part (MAP), which defines the
methods and mechanisms of communication in
wireless networks and employs the services
of the SS7 transactional capabilities
application part (TCAP). An SMS service
layer makes use of the MAP signaling
capabilities and enables the transfer of
short messages between the peer entities. |
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| The capabilities of the
terminal vary depending on the wireless
technology supported by the terminal. Some
functionality, although defined in the SMS
specification for a given wireless
technology, may not be fully supported in
the terminal, which may represent a
limitation in the services that the carrier
can provide. This trend, however, is
disappearing as service providers’ merger
and acquisition activity demands uniform
functionality across all the constituents of
the parent companies. Also, some
manufacturers may include additional
functionality, not considered in the
specification, attempting to offer a more
attractive product for service providers as
well as end users. This will be the case
more often as service provider continue to
incorporate SMS into their
revenue-generating and customer-loyalty
strategies. |
Signaling Elements
| IThe MAP layer defines
the operations necessary to support SMS.
Both American and international standards
bodies have defined a MAP layer using the
services of the SS7 TCAP. The American
standard is published by Telecommunication
Industry Association and is referred to as
IS-41. The international standard is defined
by the European Telecommunications Standards
Institute (ETSI) and is referred to as GSM
MAP. |
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| The following basic MAP
operations are necessary to provide the
end-to-end SMS: |
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Routing Information Request - Before
attempting delivery of a short |
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message, the SMSC must receive routing
information to determine the serving MSC
for the mobile device at the time of the
delivery attempt. This is accomplished
by way of an interrogation of the
destination handset’s HLR, which is
accomplished via the use of the
SMSrequest and
SendRoutingInfoForShortMsg mechanisms in
IS-41 and GSM, respectively. |
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Point-to-Point Short Message Delivery
- The mechanism provides a means |
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for the
SMSC to transfer a short message to the
MSC that is serving the addressed mobile
device. After the address of said MSC
has been obtained from the station’s HLR,
the short message delivery operation
provides a confirmed delivery service.
The operation works in conjunction with
the base station subsystem while the
message is being forwarded from the MSC
to the MS. Therefore, the outcome of the
operation comprises either success (such
as delivery to the mobile) or failure
caused by one of several possible
reasons. The point-to-point short
message delivery is accomplished via the
use of the short message
delivery-point-to-point (SMD-PP) and
forwardShortMessage mechanisms in IS-41
and GSM, respectively. |
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Short Message Waiting Indication -
The operation is activated when a short |
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message
delivery attempt by the SMSC fails due
to a temporary failure, such as the
station being unregistered, and provides
a means for the SMSC to request the HLR
to notify the SMSC when the indicated
mobile device becomes available. This
short message waiting indication is
realized via the use of the
SMS_notification indicator and
set_message_waiting_data mechanisms in
IS-41 and GSM, respectively. |
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Service Center Alert - The operation
provides a means for the HLR to inform |
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the
SMSC, which has requested a notification
that a specific mobile device is now
recognized by the mobile network to be
available. This service center alert is
accomplished via the use of the
SMS_notification and
alert_service_center mechanisms in IS-41
and GSM, respectively. |
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Service Elements |
| SMS is comprised of
several service elements relevant to the
reception and submission of short messages: |
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Message Expiration - The SMSC will
store and reattempt delivery of |
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messages for unavailable recipients
until either the delivery is successful
or the expiration time - set on a
per-message basis or on a platform-wide
basis - arrives. |
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Priority - This is the information
element provided by an SME to indicate
the |
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urgent
messages and differentiate them from the
normal priority messages. Urgent
messages usually take priority over
normal messages, regardless of the time
of arrival to the SMSC platform. |
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Message Escalation - The SMSC stores
the message for a period no longer |
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than
the expiration time (it is assumed that
the escalation time is smaller than the
expiration time associated with the
message), and after said escalation time
expires, the message will be sent to an
alternate message system (such as a
paging network or an e-mail server) for
delivery to the user. |
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| In addition, SMS
provides a time stamp reporting the time of
submission of the message to the SMSC and an
indication to the handset of whether or not
there are more messages to send (GSM) or the
number of additional messages to send
(IS-41). |
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Subscriber Services |
| SMS comprises two basic
point-to-point services: |
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Mobile-originated short message (MO-SM) |
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Mobile-terminated short message (MT-SM) |
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| Mobile-originated (MO)
short messages are transported from the
MO-capable handset to the SMSC and can be
destined to other mobile subscribers or for
subscribers on fixed networks such as paging
networks or Internet protocol (IP) networks
(including the Internet and private e-mail
networks). Mobile-terminated (MT) short
messages are transported from the SMSC to
the handset and can be submitted to the SMSC
by other mobile subscribers via MO-SM or by
other sources such as voice-mail systems,
paging networks, or operators. |
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| Mobile-originated (MO)
short messages are transported from the
MO-capable handset to the SMSC and can be
destined to other mobile subscribers or for
subscribers on fixed networks such as paging
networks or Internet protocol (IP) networks
(including the Internet and private e-mail
networks). Mobile-terminated (MT) short
messages are transported from the SMSC to
the handset and can be submitted to the SMSC
by other mobile subscribers via MO-SM or by
other sources such as voice-mail systems,
paging networks, or operators. |
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| For MT-SM, a report is
always returned to the SMSC either
confirming the short message delivery to the
handset or informing the SMSC of the short
message delivery failure and identifying the
reason for failure (cause code). Similarly,
for MO-SM, a report is always returned to
the handset either confirming the short
message delivery to the SMSC or informing of
delivery failure and identifying the reason. |
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| Depending on the access
method and the encoding of the bearer data,
the point-to-point short messaging service
conveys up to 190 characters to an SME in
GSM networks and from 120 to 205 in IS-41
networks. |
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| In GSM networks, the
type of messaging service is identified by
the protocol identifier information element,
which identifies the higher-level protocol
or interworking being used. Examples are
telex, group 3 telefax, X.400 messaging,
European Radio Messaging System (ERMES), and
voice telephone. |
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| In IS-41 networks, the
service type is distinguished by use of the
teleservice identifier. Basic teleservices
include the following: |
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Cellular messaging teleservice (CMT) |
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Cellular paging teleservice (CPT) |
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Voice-mail notification teleservice (VMN) |
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| CMT differs from the
CPT due to the inclusion of a reply
mechanism that enables a user or network
acknowledgment to be selected on a
per-message basis. The user acknowledgment
includes a response code that paves the way
for powerful interactive services between
SMSCs. |
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| Many service
applications can be implemented by combining
these service elements. Aside from the
obvious notification services, SMS can be
used in one-way or interactive services
providing wireless access to any type of
information anywhere. By leveraging new
emerging technologies that combine browsers,
servers, and new markup languages designed
for mobile terminals, SMS can enable
wireless devices to securely access and send
information from the Internet or intranets
quickly and cost-efficiently. One of these
technologies where SMS can provide a
cooperative, rather than a competitive,
approach is the WAP, which allows transport
of data for mobile wireless users. |
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| A generic network
infrastructure for realizing the innovative
SMS services is depicted in Picture 2. |
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Picture 2. Network
Infrastructure |
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| Some of the potential
applications of SMS technology, utilizing
both MT-SM and MO-SM where appropriate,
include the following: |
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Notification Services - Notification
services are currently the most widely |
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deployed SMS services. Examples of
notification services using SMS include
the following: |
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Voice/fax message notification,
which indicates that voice or fax
mail |
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messages are present in a voice
mailbox |
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E-mail notification, which indicates
that e-mail messages are present in |
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an
e-mail mailbox |
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Reminder/calendar services, which
enable reminders for meetings and |
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scheduled appointment |
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E-mail Interworking - Existing
e-mail services can be easily integrated
with |
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SMS to
provide e-mail to short messaging and
mobile e-mail and message escalation. |
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Paging Interworking - Paging
services integrated with SMS allow
digital |
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wireless subscribers to be accessible
via existing paging interfaces, as well
as escalation of messages. |
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Information Services - A wide
variety of information services can be
provided |
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by the
SMS, including weather reports, traffic
information, entertainment information
(e.g., cinema, theater, concerts),
financial information (e.g., stock
quotes, exchange rates, banking,
brokerage services), and directory
assistance. SMS can support both push
(MT) and pull (MO) approaches to allow
not only delivery under specific
conditions but also delivery on demand,
as a response to a request. |
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WAP
Integration - SMS can deliver
notifications for new WAP messages to |
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wireless subscribers but can also be
used as the transport mechanism for WAP
messages. These messages can contain
diverse information from sources that
include databases, the World Wide Web,
e-mail servers, etc. |
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Mobile Data
Services |
| The SMSC can also be
used to provide short wireless data. The
wireless data may be in interactive services
where voice calls are involved. |
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| Some examples of this
type of service include fleet dispatch,
inventory management, itinerary
confirmation, sales order processing, asset
tracking, automatic vehicle location, and
customer contact management. Other examples
may be interactive gaming, instant
messaging, mobile chat, query services,
mobile banking, etc. |
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Customer Care and
Management |
| The SMSC can also be
used to transfer binary data that can be
interpreted by the mobile device without
presentation to the customer. This
capability allows the operators to
administer their customers by providing a
mechanism for programming the mobile device.
Examples of such services include mobile
device programming, which allows customer
profiles and subscription characteristics to
be downloaded to the mobile device
(customers can be activated/deactivated
based on the data downloaded) and advice of
charge, which enables the SMS to be used to
report charges incurred for the phone call
(e.g., calls made when roaming). |
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| One interesting method
to provide customer support is to offer a
list of answers to frequently asked
questions via short message. SMS also can be
used to distribute general information about
other products and services being offered by
the service provider, thus guaranteeing
maximum penetration of the advertising over
the existing customer base. In a different
scenario, a service provider may want to
deliver short messages to subscribers to
remind them of, for example, past-due
payments, instead of reminding them over
traditional mail or courier delivery,
therefore reducing cost and ensuring that
the message is delivered to its destination
in a timely manner. |
Mobile-Terminated Short
Message Example
| Picture 3 depicts the
successful MT–SM scenario for GSM. |
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Picture 3. MT–SM Scenario (GSM) |
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1. |
The
short message is submitted from the ESME
to the SMSC. |
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2. |
After
completing its internal processing, the
SMSC interrogates the HLR and |
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receives the routing information for the
mobile subscriber. |
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3. |
The
SMSC sends the short message to the MSC
using the forward short |
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message
operation. |
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4. |
The MSC
retrieves the subscriber information
from the VLR. This operation |
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may
include an authentication procedure. |
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5. |
The MSC
transfers the short message to the MS. |
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6. |
The MSC
returns to the SMSC the outcome of the
forwardShortMessage |
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operation. |
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7. |
If
requested by the ESME, the SMSC returns
a status report indicating delivery |
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of the
short message. |
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Picture 4. MT Short Message Scenario
(IS–41) |
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1. |
The
short message is submitted from the ESME
to the SMSC. |
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2. |
The
SMSC sends an acknowledgement to the
ESME, indicating reception of t |
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he
short message. |
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3. |
After
completing its internal processing, the
SMSC interrogates the HLR. |
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4. |
The HLR
sends the routing information for the
mobile subscriber to the |
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SMSC. |
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5. |
The
SMSC sends the short message to the MSC
using the SMSDPP Invoke |
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operation. |
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6. |
The MSC
transfers the short message to the MS. |
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7. |
The MS
returns an acknowledgement to the MSC. |
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8. |
The MSC
returns to the SMSC the outcome of the
SMSDPP operation. |
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9. |
If
requested by the ESME, the SMSC returns
a delivery receipt indicating |
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successful delivery of the short
message. |
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Mobile-Originated Short
Message Example
| Picture 5 depicts the
successful MO–SM scenario, utilizing the GSM
method. The IS–41 method for the MO-SM
scenario is depicted in Picture 6. |
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Picture 5. MO–SM
Scenario (GSM) |
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- The MS is powered on and registered
with the network.
- The MS transfers the SM to the MSC.
- The MSC interrogates the VLR to verify
that the message transfer does not violate
the supplementary services invoked or the
restrictions imposed.
- The MSC sends the short message to the
SMSC using the forwardShortMessage
operation.
- The SMSC delivers the short message to
the SME (and optionally receives
acknowledgment).
- The SMSC acknowledges to the MSC the
successful outcome of the
forwardShortMessage operation.
- The MSC returns to the MS the outcome
of the MO-SM operation.
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Picture 6. MO–SM
Scenario (IS–41) |
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- The MS transfers the SM to the MSC.
- The MSC interrogates the home SMSC to
verify that the message transfer does not
violate the supplementary services invoked
or the restrictions imposed. The MSC sends
the short message to the home SMSC using
the SMSPP Invoke operation
- The SMSC delivers an acknowledgment to
the MSC.
- The MSC returns order release to the
MS.
- The SMSC queries the HLR for the
location of the destination MS.
- The HLR returns the destination (MSC)
serving the destination MS.
- The SMSC delivers SM to the MSC
serving the destination MS.
- The SMSC delivers the short message to
the MS.
- The MS acknowledges to the MSC the
successful outcome of the SMSDPP
operation.
- The MSC returns to the SMSC the
outcome of the MO–SM operation (delivery
successful).
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SMS Applications
| SMS was initially
designed to support limited-size messages,
mostly notifications and numeric or
alphanumeric pages. While these applications
are and will continue to be widely used,
there are more recent niches that SMS still
can exploit. |
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| Short bursts of data
are at the heart of many applications that
were restricted to the world of data
networks with fixed terminals attached to a
local-area network (LAN) or wide-area
network (WAN). However, many of these
applications are better served if the data
communication capabilities could be added to
the mobility of the station. Thus, a waiter
who can charge a customer's credit card
right at the table, at any time, instead of
going to a fixed POS terminal located by the
register will be able to help customers in a
faster, more convenient way. |
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| Also, the ability to
track the location of a moving asset such as
a truck or its load is very valuable for
both providers and clients. This
application, again, just needs to
interchange small amounts of information,
such as the longitude and latitude at a
current time of the day, and perhaps other
parameters like temperature or humidity. |
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| This application does
not necessarily require the monitored entity
to be in movement. The requirements are
basically short, bursty data and a location
that has digital network coverage. For
example, in a neighborhood, it would be
faster, easier, and cheaper to drive a truck
from the local power company, which
interrogates intelligent meters to obtain
their current readings and then forwards
them via short message to a central data
processing center to generate the billing.
Similarly, delivery trucks could be alerted
of the inventory of a customer running low,
when the truck is close to the customer’s
facilities. The truck driver could place a
quick phone call to the customer to offer a
short-time replenishment at a low cost for
the distributor. |
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| Another family of
applications that can use SMS as a data
transport mechanism is banking. It is no
secret that automated teller machine (ATM)
and Internet transactions are less costly
than transactions completed at a branch.
Internet transactions are even cheaper than
ATM transactions. Therefore, enabling
wireless subscribers to check their
balances, transfer funds between accounts,
pay their bills and credit cards is
valuable, not only for the subscriber but
also for financial institutions. |
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| Entertainment
applications are also good drivers of SMS
usage. Examples of these are simple short
message exchanges between two parties (“texting”)
or between multiple participants (“chat”).
Also, delivery of information that the
subscriber can tailor to his or her
lifestyle represents an attractive
proposition for wireless users. |
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| Wireless Web browsing
allows the users to search for information
without the physical restrictions of a PC.
College students certainly appreciate not
having to go to the computer lab or their
dorm to check e-mail or find out what the
required book is for the semester that is
about to start. |
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| E-mail continues to be
by far the most used wireless data
application. However, handsets are evolving
quickly and are including more and more
functionality that supports newer
applications at the same time that user
friendliness increases. Probably the next
big success beyond wireless Web will be
Internet shopping and other e-commerce
applications such as electronic coupons,
advertising, etc. |
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| The potential for
applications is enormous, and new needs
appear to arise constantly, demanding a
solution that may travel over SMS. |
Test Your
Knowledge
1. SMS guarantees message delivery even if
the terminal is turned off when the message
is sent.
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