ZyXEL Communications ZYWALL USG 2000 Manual page 206

Chapter 10 Interface
If the signal strength of a 3G network is too low, the 3G card may switch to an
available 2.5G or 2.75G network. See the following table for a comparison
between 2G, 2.5G, 2.75G and 3G of wireless technologies.
Table 54 2G, 2.5G, 2.75G, 3G and 3.5G Wireless Technologies
MOBILE PHONE AND DATA STANDARDS
NAME TYPE
GSM-BASED
2G Circuit- GSM (Global System for Mobile
switched Communications), Personal
Handy-phone System (PHS), etc.
2.5G Packet- GPRS (General Packet Radio
switched Services), High-Speed Circuit-
Switched Data (HSCSD), etc.
2.75G Packet- Enhanced Data rates for GSM
switched Evolution (EDGE), Enhanced
GPRS (EGPRS), etc.
3G Packet- UMTS (Universal Mobile
switched Telecommunications System), a
third-generation (3G) wireless
standard defined in ITU
specification, is sometimes
marketed as 3GSM. The UMTS
uses GSM infrastructures and W-
CDMA (Wideband Code Division
Multiple Access) as the air
interface.
3.5G Packet- HSDPA (High-Speed Downlink
switched Packet Access) is a mobile
telephony protocol, used for
UMTS-based 3G networks and
allows for higher data transfer
speeds.
To change your 3G WAN settings, click Network > Interface > Cellular.
Note: Install (or connect) a compatible 3G card to use a cellular connection. See
Chapter 52 on page 803
206
CDMA-BASED
Interim Standard 95 (IS-95), the
first CDMA-based digital cellular
standard pioneered by Qualcomm.
The brand name for IS-95 is
cdmaOne. IS-95 is also known as
TIA-EIA-95.
CDMA2000 is a hybrid 2.5G / 3G
protocol of mobile
telecommunications standards that
use CDMA, a multiple access
scheme for digital radio.
CDMA2000 1xRTT (1 times Radio
Transmission Technology) is the
core CDMA2000 wireless air
interface standard. It is also known
as 1x, 1xRTT, or IS-2000 and
considered to be a 2.5G or 2.75G
technology.
CDMA2000 EV-DO (Evolution-Data
Optimized, originally 1x Evolution-
Data Only), also referred to as EV-
DO, EVDO, or just EV, is an
evolution of CDMA2000 1xRTT and
enables high-speed wireless
connectivity. It is also denoted as
IS-856 or High Data Rate (HDR).
for details.
DATA
SPEED
ZyWALL USG 2000 User's Guide
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