Cisco 1751 Datasheet page 3

and serial with DSU/CSU options for primary and backup WAN connectivity. The voice interface cards support
Foreign Exchange Office (FXO), Foreign Exchange Station (FXS), Network and User Side Voice BRI (ISDN BRI NT/
TE), Ear & Mouth (E&M), direct inward dial (DID), and T1/E1 Multiflex VWICs. Additionally, an Ethernet
interface card provides the Cisco 1751 Router with dual-Ethernet capability to support the external broadband
modem devices. See Figure 3.
Figure 3
Cisco 1751 Router Incorporating Ethernet WAN Interface Card (WIC) Deployed with Broadband Modem
In addition, dual-Ethernet capability on the Cisco 1751 Router enables the creation of perimeter/DMZ (demilitarized
zone) LANs to enhance security by physically separating private and public data. See Figure 4.
Figure 4
Cisco 1751 Router Incorporating Ethernet WIC to Deploy Perimeter/DMZ LAN
Combined, these interfaces support a comprehensive set of applications, including multiservice voice/video/data/fax
integration, Frame Relay, ISDN BRI, SMDS, X.25, broadband DSL and cable services, and VPNs.
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