User Manual

23
Cisco Connected Grid 3G Module Installation and Configuration Guide
OL-25991-01
Software Overview
segregated, the voice traffic goes to the Mobile Switching Center (MSC), while the data traffic is sent to
the GGSN. From the GGSN, the data packets either go directly to the internet or they can be backhauled
to the customer data center for a VPN connection.
Universal Mobile Telecommunications System (UMTS) evolved from GSM and is a 3G wireless system
that delivers high-bandwidth data and voice services to mobile users. UMTS has a new air interface
based on Wideband Code Division Multiple Access (W-CDMA) and an IP core network based on
general-packet radio service (GPRS). The nodes in a UMTS network are almost the same as that of a
GSM/GPRS network. BTS and BSC have been renamed to Node B and Radio Network Controller
(RNC), respectively.
UMTS addresses the growing demand of mobile and Internet applications for new capacity in the
overcrowded mobile communications sky. The new network increases transmission speed to 2 Mbps per
mobile user and establishes a global roaming standard.
UMTS (Universal Mobile Telecommunication System) (W-CDMA) is standardized by 3GPP and offers
the following:
• W-CDMA radio access technology, in addition to the existing GSM and GPRS radio access
networks.
• W-CDMA uses 5 MHz bandwidth radio carriers. Up to 384kb/s initially. Capable of 2 Mb/s, but not
offered commercial yet.
• HSPA is an upgrade to W-CDMA (includes HSDPA (High Speed Downlink Packet Access) and
HSUPA (High-Speed Uplink Packet Access).
– HSDPA:Various categories support up to 10 Mb/s
– HSUPA:uplink speed up to 5.76 Mb/s
High Speed Packet Access (HSPA) is a collection of two mobile protocols—High Speed Downlink
Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves
the performance of existing WCDMA/UMTS protocols. HSDPA and HSUPA provide increased
performance by using improved modulation schemes and by refining the protocols by which 3G modem
and base stations communicate.
These improvements lead to a better utilization of the existing radio bandwidth provided by WCDMA.
HSPA improves the end-user experience by increasing peak data rates of up to 14 Mbit/s in the downlink
and 5.76 Mbit/s in the uplink. It also reduces latency and provides up to five times more system capacity
in the downlink and up to twice as much system capacity in the uplink, reducing the production cost per
bit compared to original WCDMA protocols.
CDMA Data Network Overview
The Code Division Multiple Access (CDMA) is a digital cellular network developed to deliver
high-speed and improved wireless data service through increased capacity by allowing users to share a
band of frequencies. CDMA is being adopted by many administrators for cellular networks due to its
greater throughput which is six times that of Time Division Multiple Access (TDMA-) or Frequency
Division Multiple Access (FDMA)-based systems.
A typical CDMA network includes terminal equipment, mobile termination, base transceiver station
(BTS), base station controller (BSC), packet data serving node (PDSN), and other data network entities.
The PDSN is the interface between a BSC and a internet gateway.
A typical CDMA network includes a PDSN and a branch office with the 3G wireless Modular and Fixed
Cisco ISRs. The branch office connects to a radio tower and a BTS. The BTS connects to a BSC, which
contains a component called the packet control function (PCF). The PCF communicates with the Cisco
PDSN for data communication and with the mobile switching center (MSC) for voice.