Huawei Technologies Co. Ltd EM820W 사용자 설명서

2.1 WAN Access

Depending on the network environment provided by carriers, users can access the network by
using CE1/CT1, E1/T1-F, 3G, FE/GE, ADSL, VDSL, G.SHDSL, Integrated Services Digital
Network (ISDN), CPOS, AS, xPON or SA. The ARs provide dual-uplink to ensure service
reliability. The ARs provide the following services for access users:

As shown in

Figure 2-1

, enterprise A accesses the Internet using ADSL; enterprise B accesses

the Internet using FE and CE1 dual-uplink; enterprise C accesses the Internet using G.SHDSL;
enterprise D accesses the Internet using 3G.

Figure 2-1 WAN access

Enterprise A

Enterprise B

Enterprise D

Enterprise C

E1/CE1

G.SHDSL

Internet

ADSL

2.2 VPN Access

The headquarters and branches use the ARs establish a VPN and connect to the Internet. The
enterprise establishes a VPN and uses GRE, MPLS, or IPSec VPN to ensure data security. The
employees on a business trip use IPSec VPN tunnels to communicate with the headquarters.

As shown in

Figure 2-2

, the headquarters is connected to the Internet by using the

AR2200&3200, and provides services for all employees. The LAN of the branch connects to

Huawei AR G3 Series Enterprise Routers
Product Description

2 Network Applications

Issue 02 (2012-04-20)

Huawei Proprietary and Confidential