If any application could be thought of as the “killer application,”
messaging would certainly rank high on the list. First-generation
digital cellular brought new data handling capabilities to
the mobile community when a new service called SMS or Short
Message Service was embedded into cellular protocols. All
GSM phones support SMS but not all TDMA or CDMA phones
fully support SMS yet. GSM was the first protocol to use SMS
so the handsets have all caught up to the feature; the other protocols
are working on enabling SMS in the network as more
TDMA and CDMA handsets incorporate the ability to send an
SMS. Remember—all digital phones can receive text messages.
Figure 2-4 illustrates an SMS network overlay.
Carriers in Europe report SMS revenues as up to 15 percent
of revenues and an even greater percent of profits. Global SMS traffic is estimated at 15 billion messages by December
2001.* While SMS is immensely popular in Europe, it will be
the first step in most carrier messaging strategies and will
therefore be the first non-voice application that the majority of
American consumers will experience. Although mainstream
launches and promotions of SMS have taken place, widespread
adoption is far from complete.
SMS teaches consumers to use wireless devices for nonvoice
services, and it will be the bearer for the next stage of
messaging that incorporates elements other than simple text—
graphics, sound, and specific formatting. Before United States
customers can enjoy the same widespread usage as GSM users,
however, several problems must be solved.
Not all SMS messaging is created equal. The number of
characters that can be sent using SMS varies by protocol and
carrier. Typically GSM sends 160 characters, TDMA sends 150
characters, and CDMA can handle up to about 200. Some
phones only receive and cannot send SMS. Addressing and
interconnectivity for SMS is a major challenge for substantial
growth of SMS traffic. Users of CDMA cannot send SMS to
TDMA users.
A second problem area is billing. Billing impacts the adoption
of SMS because most consumers will be unsure of the
need for SMS and will not have any reference point for usage.
Billing can be in “buckets of messages,” “per SMS,” or free.
Most carriers will launch SMS with a period of free SMS messages
before moving to the primary offer of a bucket of SMS
messages (200–800) for $4 to 8 per month.
Speed and latency offer another potential problem area in
the United States. This was a problem in Europe six years ago,
but because SMS is a mature technology in Europe, latency
has been “fine-tuned” out. A typical SMS message is very fast—
less than 5 seconds from send to receive. At times in the
United States, however, the SMS traffic is so heavy (holidays,
etc.) that the delay is measured in hours not seconds. SMS
quickly loses value as latency increases. Carriers control latency
by adding processing power to the Short Message Service
Center (SMSC).
Every technology-based service such as cellular or the
Internet constantly evolves into something different and, hopefully,
better. SMS is no different; it will migrate to newer versions
such as Smart Messaging, Instant Messaging,
Multimedia Messaging, and Enhanced SMS (EMS or E-SMS).
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 has been introduced,
including email, 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 (POS), and other field-service applications such
as automatic meter reading, remote sensing, and locationbased
services. Additionally, integration with the Internet
spurred the development of Web-based messaging and other interactive applications such as instant messaging, gaming, and
chatting.
Clearly, mobile messaging is a valuable application that is
gaining popularity in both the business and consumer sectors.
Mobile messaging services will continue into the next-generation
networks, and multimedia messaging will emerge as more
bandwidth becomes available.