ZyXEL Communications 1000 Manual De Usuario

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Chapter 13 Interfaces
ZyWALL USG 1000 User’s Guide
300
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.
To change your 3G WAN settings, click Configuration > Network > Interface > 
Cellular
Note: Install (or connect) a compatible 3G card to use a cellular connection. See 
 for details.
Note: The WAN IP addresses of a ZyWALL with multiple WAN interfaces must be on 
different subnets. 
Table 63   2G, 2.5G, 2.75G, 3G and 3.5G Wireless Technologies
NAME TYPE
MOBILE PHONE AND DATA STANDARDS
DATA 
SPEED
GSM-BASED
CDMA-BASED
2G Circuit-
switched
GSM (Global System for Mobile 
Communications), Personal 
Handy-phone System (PHS), etc.
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.
Slow
Fast
2.5G
Packet-
switched
GPRS (General Packet Radio 
Services), High-Speed Circuit-
Switched Data (HSCSD), etc.
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.  
2.75G Packet-
switched
Enhanced Data rates for GSM 
Evolution (EDGE), Enhanced GPRS 
(EGPRS), etc. 
3G Packet-
switched
UMTS (Universal Mobile 
Telecommunications System), a 
third-generation (3G) wireless 
standard defined in ITU
A
 
specification, is sometimes 
marketed as 3GSM. The UMTS 
uses GSM infrastructures and W-
CDMA (Wideband Code Division 
Multiple Access) as the air 
interface.
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).
3.5G
Packet-
switched
HSDPA (High-Speed Downlink 
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.