Cisco Cisco 3G Wireless WAN Enhanced High-Speed WAN Interface Card Guía De Información
Q&A
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Cisco 3G Wireless WAN Enhanced High-Speed
WAN Interface Cards for Cisco Integrated Services
Routers Generation 2 Q&A
WAN Interface Cards for Cisco Integrated Services
Routers Generation 2 Q&A
Q. What is 3G? What are the 3G standards groups?
A. Third-generation (3G) is the term for the latest generation of mobile services, which provide advanced voice
communications and high-speed data connectivity, including access to the Internet, mobile data applications,
and multimedia content. The International Telecommunications Union (ITU), working with industry-standards
groups from around the world, has defined the technical requirements and standards as well as the spectrum
for 3G systems under the International Mobile Telecommunications-2000 (IMT-2000) program. The ITU
requires that IMT-2000 (3G) networks deliver (among other capabilities) improved system capacity and
spectrum efficiency over second-generation (2G) systems and that they support data services at minimum
transmission rates of 144 kbps in mobile (outdoor) and 2 Mbps in fixed (indoor) environments.
Q. What is the difference between EVDO and HSPA?
A. Evolution-Data Optimized (EVDO) and high-speed packet access (HSPA) are parallel 3G data standards in
the Code Division Multiple Access (CDMA) and Global System for Mobile Communications (GSM)
environments. EVDO evolved from the Code Division Multiple Access 2000 (CDMA2000) standards, whereas
HSPA evolved from the Universal Mobile Telecommunication System (UMTS) standard that was developed
for the countries using Global System for Mobile Communications (GSM) technology.
Q. What are the associated theoretical speeds with the different 3G technologies?
A. With 3G HSPA one can get 7.2 Mbps down/5.7 Mbps up. With HSPA+ (also called 3.7G technologies) one
can get 21 Mbps down/5.7 Mbps up. The EVDO-RevA can support 3.1 Mbps down/ 1.8 Mbps up.
Q. Does the Cisco 3G Enhanced High-Speed WAN Interface Card (EHWIC) support Mobile IP (MIP), or Simple
IP only?
A. The CDMA 3G EHWIC SKUs support MIP on the modem. Depending upon the configuration on the carrier
network, it could be set to either MIP only or MIP preferred mode. In the MIP preferred mode, when MIP fails,
the modem falls back to Simple IP. The GSM 3G wireless WAN (WWAN) SKUs do not have a Mobile IP
stack.
Q. How does the modem select the service to which to attach? Does it switch to a better service when one
is available?
A. Yes. For GSM networks, the modem always looks for HSPA/HSPA+ as the first choice. If HSPA/HSPA+ is not
available, the modem downshifts to the next best available radio network; that is, Universal Mobile
Telecommunications Service (UMTS) to Enhanced Data rates for GSM Evolution (EDGE) and finally to
General Packet Radio Service (GPRS). If you have only EDGE service, the modem continues to scan in the
background for UMTS or HSPA service. If the UMTS or HSPA service becomes available, the modem
automatically switches to that service. For CDMA networks, the modem always looks for EVDO Rev A first,
then Rev 0, and then 1xRTT.