Tannoy Z600 사용자 설명서

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White Paper
 
Z600
31
September 2003
General Packet Radio Services
The introduction of GPRS (General Packet Radio 
Services) is one of the key steps in the evolution of 
today’s GSM networks for enhancing the capabili-
ties of data communication. Data traffic is increas-
ing enormously (over both wired and wireless 
networks), with the growth in demand for Internet 
access and services paralleling that for mobile 
communications. Users want access to the Internet 
while they are away from their offices and homes, 
and surveys have found that the vast majority of 
business professionals want the ability to send and 
receive e-mail, browse the WAP and transmit text 
and graphics on a portable device. That is why the 
main applications driving Mobile Internet develop-
ment are e-mail clients and WAP browsers. 
The demand for high-speed Internet access will be 
the key driver for coming generations of wireless 
services, and GPRS can deliver the necessary 
speed. GPRS allows innovative services to be cre-
ated, enabling new and previously inaccessible 
market segments to be addressed and increasing 
customer loyalty. 
GPRS applications can be developed as both hori-
zontal and vertical. Vertical applications are spe-
cific, including those for operations such as 
reaching police and emergency, taxi, delivery or 
automated services (vending machines, supervi-
sion, vehicle tracking). Horizontal applications are 
more generic and include those for Internet access, 
e-mail, messaging, e-commerce and entertain-
ment. 
GPRS is able to take advantage of the global cov-
erage of existing GSM networks. Applications 
developed for GPRS can be deployed on a large 
scale and can reap the associated benefits. GPRS 
also provides a secure medium for connections to 
private networks, banking and financial services.
With GPRS, the Z600 sends data in “packets” at a 
very high speed. The Z600 remains connected to 
the network at all times, using transmission capac-
ity only when data is sent or received. 
Using GPRS in the Z600
Instead of occupying an entire voice channel for 
the duration of a data session, the Z600 sends/
receives data in small packets, as needed, much 
like IP on the Internet. Because of this, the Z600 
maintains a constant online connection, its data 
transmission abilities summoned by the application 
in use on an as-needed basis.
The GPRS specification includes four coding 
schemes – CS1, CS2, CS3 and CS4 – that allow 
data speeds of 9,050 bps, 13,400 bps, 15,600 bps 
and 21,400 bps respectively. The Z600 works with 
all four coding schemes, but data speed will natu-
rally vary according to network configuration. At 
the moment, CS-3 and CS-4 are not supported in 
any live network, i.e present speed is limited to 
53,600 bps.
The GSM system limits the ability to use all eight 
time slots, so the Z600 uses up to four time slots 
for receiving data, and one slot for transmitting. 
This means the speed for receiving data is up to 
85,600 bps and up to 21,400 bps for sending data.
Using GPRS with the Z600 has several advantages, 
for example:
Constant connection
Keep an open connection to an e-mail system 
or the company network, staying online to 
receive and send messages at all times. All con-
nection settings can be managed by using the 
data connections feature.
High speed
Gain access automatically to increased band-
width when downloading large files, images etc.
Cost efficient
Use transmission capacity only when needed, 
thus reducing costs.
WAP over GPRS
Access the Internet via WAP at high speed and 
with a constant connection.
E-mail over GPRS
Remain connected to an e-mail system while 
reading and preparing messages, (which are 
sent at a high speed).
Data communication