21-08-2012, 05:00 PM
IMPLEMENTION OF 2.5G
[attachment=32332]
Services Offered by 2.5G Technology
Always on" internet access
Multimedia messaging service (MMS)
Push to talk over cellular (PoC/PTT)
Instant messaging and presence—wireless village
Internet applications for smart devices through wireless application protocol (WAP)
Point-to-point (P2P) service: inter-networking with the Internet (IP)
Addressing
A GPRS(2.5G) connection is established by reference to its access point name (APN). The APN defines the services such as
wireless application protocol (WAP) access,
short message service (SMS),
multimedia messaging service (MMS), and for
Internet communication services
Eg. email and World Wide Web access.
In order to set up a GPRS connection for a wireless modem, a user must specify an APN, optionally a user name and password, and very rarely an IP address, all provided by the network operator.
Usability
The maximum speed of a GPRS connection offered in 2003 was similar to a modem connection in an analog wire telephone network, about 32-40 kbit/s
Latency is very high; round-trip time (RTT) is typically about 600-700 ms and often reaches 1 s.
GPRS is typically prioritized lower than speech, and thus the quality of connection varies greatly.
Devices with latency/RTT improvements are generally available.
Also, network upgrades of features are available with certain operators.
With these enhancements the active round-trip time can be reduced, resulting in significant increase in application-level throughput speeds.
General Support Functions :
The GPRS core network provides mobility management, session management and transport for Internet Protocol packet services in GSM and WCDMA networks.
The core network also provides support for other additional functions such as billing and lawful interception.
It was also proposed, at one stage, to support packet radio services in the US D-AMPS TDMA system, however, in practice, all of these networks have been converted to GSM so this option has become irrelevant.
Serving GPRS Support Node (SGSN)
Maximum data rate of approx. 60 kbit/s (150 kbit/s for EDGE) per subscriber
Connect via frame relay or IP to the Packet Control Unit using the Gb protocol stack
Accept uplink data to form IP packets
Encrypt down-link data, decrypt up-link data
Carry out mobility management to the level of a cell for connected mode mobiles
[attachment=32332]
Services Offered by 2.5G Technology
Always on" internet access
Multimedia messaging service (MMS)
Push to talk over cellular (PoC/PTT)
Instant messaging and presence—wireless village
Internet applications for smart devices through wireless application protocol (WAP)
Point-to-point (P2P) service: inter-networking with the Internet (IP)
Addressing
A GPRS(2.5G) connection is established by reference to its access point name (APN). The APN defines the services such as
wireless application protocol (WAP) access,
short message service (SMS),
multimedia messaging service (MMS), and for
Internet communication services
Eg. email and World Wide Web access.
In order to set up a GPRS connection for a wireless modem, a user must specify an APN, optionally a user name and password, and very rarely an IP address, all provided by the network operator.
Usability
The maximum speed of a GPRS connection offered in 2003 was similar to a modem connection in an analog wire telephone network, about 32-40 kbit/s
Latency is very high; round-trip time (RTT) is typically about 600-700 ms and often reaches 1 s.
GPRS is typically prioritized lower than speech, and thus the quality of connection varies greatly.
Devices with latency/RTT improvements are generally available.
Also, network upgrades of features are available with certain operators.
With these enhancements the active round-trip time can be reduced, resulting in significant increase in application-level throughput speeds.
General Support Functions :
The GPRS core network provides mobility management, session management and transport for Internet Protocol packet services in GSM and WCDMA networks.
The core network also provides support for other additional functions such as billing and lawful interception.
It was also proposed, at one stage, to support packet radio services in the US D-AMPS TDMA system, however, in practice, all of these networks have been converted to GSM so this option has become irrelevant.
Serving GPRS Support Node (SGSN)
Maximum data rate of approx. 60 kbit/s (150 kbit/s for EDGE) per subscriber
Connect via frame relay or IP to the Packet Control Unit using the Gb protocol stack
Accept uplink data to form IP packets
Encrypt down-link data, decrypt up-link data
Carry out mobility management to the level of a cell for connected mode mobiles