An AR can create a PPP session with the remote end by using PPPoE, and implement access
control and accounting.
An AR can function as the PPPoE server to connect to different types of PPPoE clients on the
Ethernet or function as a dial-up PPPoE client.
ADSL
An Asymmetric Digital Subscriber Line (ADSL) implements high-speed data transmission over
twisted-pair copper wire by using idle high frequency ranges through a regular telephone line,
but with a different modulation method. With an uplink band from 26 kHz to 138 kHz, ADSL
can provide transmission rates up to 640 kbit/s; with a downlink band from 138 kHz to 1.104
MHz, ADSL can provide up to an 8 Mbit/s transmission rate.
The current ADSL technology can provide faster transmission rates by improving the modulation
rate, coding gain, the initialization state machine, by reducing the frame head overhead, and by
using enhanced signal processing methods. ADSL2 can provide up to a 1024 kbit/s uplink
transmission rate and a 12 Mbit/s downlink transmission rate. By expanding the downlink band
from 1.104 MHz to 2.208 MHz, the latest ADLS technology, ADSL2+, provides a 24 Mbit/s
downlink rate.
The transmission distance and line quality affect the ADSL transmission rate. If the transmission
distance is long and the line quality is poor, the transmission rate will be low; if the transmission
distance is short and line quality is high, the transmission rate is high. When setting up a link,
ADSL automatically adjusts transmission rates based on line conditions such as distance and
noise.
The ARs transmit the LAN-side service to the wide area network by using ADSL lines.
G.SHDSL
G.Single-pair high-speed Digital Subscriber Line (G.SHDSL) implements high-speed data
transmission over twisted-pair copper wire by using idle high frequency ranges on regular
telephone line, but with different modulation methods. G.SHDSL provides transmission rates
up to 2.312 Mbit/s. The transmission distance and line quality affect the G.SHDSL transmission
rate. If the transmission distance is long and the line quality is poor, the transmission rate will
be low; if the transmission distance is short and the line quality is high, the transmission rate is
high. When setting up a link, G.SHDSL automatically adjusts transmission rates based on line
conditions such as distance and noise. G.SHDSL is a rate/distance-adaptive DSL technology.
Different from ADSL, G.SHDSL does not require a splitter.
The ARs transmit the LAN-side service to the wide area network by using SHDSL lines.
3G
The first generation (1G) uses an analog system and the second generation (2G), such as GSM
and TDMA, uses digital systems. The Third Generation (3G) integrates wireless communication
and the Internet. The 3G technology can process pictures, music, video, and provide various
information services such as web page browsing, call conferences, and E-commerce.
The ARs support WCDMA wireless interface standards. Users on a LAN can access the WAN
using 3G cards.
3.2.2 VPN
The ARs provide an IP security (IPSec) mechanism to ensure high quality, interoperable, and
cryptology-based security for communication processes. The two parties in communication can
Huawei AR1200-S Series Enterprise Routers
Product Description
3 Product Characteristics
Issue 01 (2011-08-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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