II. DATA COLLECTION MECHANISM USING CELL
BROADCAST TECHNOLOGY
One of the most important phases of this work is the data
collection mechanism, which is performed using Cell Broadcast.
This functionally allows to cellular operator improves the
communication with the subscribers getting more information
from them, the next items describe the CB technology and the
data collection process suggested in this work.
A. Cell Broadcast Technology
Cell Broadcast (CB) is a technology defined by the ETSI
(European Telecommunications Standards Institute). In UMTS
networks, defined by 3GPP (Generation Partnership Project),
also is supported this functionality. This technology also is
known as Shorts Message Service - Cell Broadcast (SMS-CB)
and its purpose is to send simultaneous messages to multiple
users who are in the coverage of a specific area. The fact of
sending simultaneous messages is what differentiates a Cell
Broadcast (CB) of the traditional SMS service, which is sent
point to point, where the message is sent individually to each
user, thus it can be said that the SMS is point to point and the
CB is point to area.
A Cellular Network of an operator contains a large amount
of cells or Base Transceiver Station (BTS) spread throughout
the territory, where the operator provides the service, the CB
allows the sending of messages to a BTS, a group of BTS
or to whole network, in this way all users have activated CB
channel receive the message. The BTS junction will depend
on diverse criteria that the Cellular Operator determines. Thus,
the CB can be compared to a radio where all the users who
are in the same frequency (in the case, CB channel) and in
the covering area of the radio station will be able to receive
the message.
The functionality of CB is a service that has no recognition
of message delivery, and the origin does not have how to
identify who received the message and the amount of users
that had received them. Activation or blocking of CB channel
in the cellular telephone can be performed manually by the
user in the same device or by the cellular operator using OTA
(Over The Air) commands.
Cell Broadcast message do not add load to cellular network,
so when some catastrophe happens (earthquake, tsunami) the
cellular networks is congested for the high degree of traffic that
occurs at the tragedy moment, CB technology does not insert
additional traffic, therefore its messages are sent by reserved
channel described in GSM Standard.