Tannoy Z600 - Manual (Page 31)

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