INVENTIA MT-101, Руководство пользователя

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8
1. Introduction
Despite the explosive expansion of mobile phone networks and the per definition digital
nature of transmission utilized by them, these networks were not well-suited for the
transfer of digital data streams until recently. The applied technologies used traditional
modem protocols. This meant that the need to use circuit-switched mode for establishing
connections and transmission capabilities was limited to point-to-point connections. Thus,
we had to do with the typical analogue circuit-switched links technology used in traditional
telephone systems adapted to the wireless digital transmission environment. A connection
established for data transmission occupied the whole voice channel. As a result,
simultaneous phone calls were impossible, and the cost of transmission depended on the
connection time rather than the amount of the transferred data. In this situation, the real-
time monitoring of units requiring constant supervision but generating a relatively small
amount of data was not possible.
The situation changed radically after GSM operators introduced data transmission services
in the GPRS (General Packet Radio Services) standard. The new technology, called the 2.5G
standard - meaning Two and a Half Generation, is a bridge between the to-date
technologies of the Second-Generation GSM networks (2G) and the Third-Generation
technology (3G - UMTS) which has been waiting for application on a wide scale. However,
broadband 3G technology is still very distant. So let us deal with the solutions available
right now.
In providing this user’s manual, we are aware that it will not answer all your questions and
address all your doubts. This is why the manual will be regularly supplemented and
modified. We ask for your comments and welcome suggestions in order to make this
manual more useful.
INVENTIA Ltd.