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MDE functions
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Applications which were unimaginable a few years ago are now possible with the help of MDe special technologies. The breakthrough of the MDE devices was due to the introduction of wide standardisations.
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The esssential standardisations are:
Uniform standard operating systems (e.g. Windows CE, DOS)
hardware standardisations (IRDA, PCMCIA)
software standardisations (class libraries, COM, CLL etc.)
Smart card readers:
It is possible to read smart cards of various types (and depending on the application and the card it is also possible to describe) with the help of the PCMCIA smart card reader and a mobile data entry device.
These devices are used especially if persons or things have to be indentified (Health insurance card, customer cards, machine cards) or if values have to be saved (calling cards, money card, prepaid cards, bonus cards etc.)
Particular advantage of the PCMCIA version:
The reader is completely integrated in a shaft. Thus no separate wires etc. have to be plugged to the device. If the mobile device is envisaged to reach the the shaft without a covering, the smart card is directly inserted into the device. (see foto)
Wired network (LAN):
Network controller connect the mobile device or notebook to the LAN. If the user is located in the office or an area connected to the network, he can connect his MDE device or notebook to it.
Disadvantage of the wired model:
It first has to be plugged in before being connected. A wireless model would be easier. (e.g. WLAN or bluetooth)
Radio network by WLAN:
Comfortable wireless connection with up to 108 Mbit/s
Contrary to bluetooth, WLAN has the advantage of providing the netowrk to a larger area. The speed also is remarkably higher.
Ideas of provision:
An office, several floors
larger areas / domains, e.g a complete stock
reach up to a maximum of 200m
comninable / upgradeable by connecting several accespoints
networking / connecting from building to building, LAN/LAN interconnection
Bluetooth network:
Many devices are bluetooth compatible. If this property is missig, it can be upgraded.
Bluetooth is a radio transmission of data for short distances (in general a few meter). Thus printer, other devices, barcode scanner, smart card reader etc. can be used while the receiver is located a few meters away.
Modem/ISDN:
Some devices also have an analog modem resp. an ISDN port. Thus a connection to a communication partner or the internet can be built up via dial-up connection (Fixed-line network telephony)
Advantages and disadvantages:
(-) Can only be used if a fixed-line network is available
(+) relatively low price dial-up
(-) A cable has to be plugged in first
• Mobile radio network (GSM /GPRS / UMTS / HSCSD):
If the opportunity to connect with this kind of network is provided, it is possible to let your device communicate almost area-wide inland and abroad. This is a great advantage if a connection nearly always hast to be built up resp. has to be available.
But it also shows some disadvantages:
• still relatively expensive (but the first providers already offer volume rates)
• a dial up has to be done at first (only aplies to GSM / HSCSD)
• relatively small transmission capacity (except for UMTS)
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