Internet Access Guide : GPRS
| Class |
Downlink Slots |
Uplink Slots |
Active Slots |
| 1 |
1 |
1 |
2 |
| 2 |
2 |
1 |
3 |
| 3 |
2 |
2 |
3 |
| 4 |
3 |
1 |
4 |
| 5 |
2 |
2 |
4 |
| 6 |
3 |
2 |
4 |
| 7 |
3 |
3 |
4 |
| 8 |
4 |
1 |
5 |
| 9 |
3 |
2 |
5 |
| 10 |
4 |
2 |
5 |
| 11 |
4 |
3 |
5 |
| 12 |
4 |
4 |
5 |
Table: GPRS multi-slot classes
Theoretically, maximum data rate of Internet access over GPRS is 115 kbps that is
achieved when all the eight time slots are used for GPRS connection.
But that is not the case referring to the available multi-slot
classes. Maximum only 5 time slots are allocated for GPRS
downlink or uplink at any given time. That's why, the
Internet experience using GPRS is like using dial-up Internet
access. But when you travel to areas not covered by faster
services such as EDGE, EV-DO, HSDPA, or Wi-Fi hotspots, GPRS often becomes the only alternative for your
Internet connection.
GPRS device is also classified based on its support
for voice and data. They are as follows:
Class A |
--> |
The device connects
simultaneously to both GPRS and GSM/TDMA. While connecting to
the Internet, the device can make and receive
a call or a message without disconnecting from the Internet.
|
Class B |
--> |
The device connects to both GPRS
and GSM/TDMA, but can use only one service at a time. When
making or receiving a call or a message, the Internet
connection (GPRS session) is suspended until the call ends.
|
Class C |
--> |
The device connects to one
service only, either GPRS or GSM/TDMA. The device must be
disconnected from the Internet (GPRS) when making or receiving
a call or a message.
|
|
