ZyXEL Communications ZyWall USG 2000 User Manual page 193

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 52 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.
A. The International Telecommunication Union (ITU) is an international organization within which governments and the private
sector coordinate global telecom networks and services.
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 53 on page 805
ZyWALL USG 2000 User's Guide
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-
A
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.
Chapter 10 Interfaces
DATA
SPEED
Slow
Fast
193