Vigor 2820 ISDN S0 series is not only a security ADSL2/2+ router for SOHO but also makes telephoning over the Internet as convenient as you can. Phone S0 port is dedicated for ISDN phone while the ISDN/ Phone S0 port is configurable for ISDN line, or ISDN phone if required. It can support multiple SIP registrars with high flexible configuration & call handling options. The analog fax machine or conventional analog phone can be attached to phone port (FXS port). You can connect your regular analog line to the Line port of Vigor 2820 V Sn. While you enable Vo IP facility, you still can access fixed line to make calls. Furthermore, you can set rules through " Digit Map" function about particular call destinations using either your SIP/ Vo IP service or the PSTN line or the ISDN line. e.g. you can route local calls via your PSTN/ISDN line (if you have a free calls package) whereas international calls can go via your preferred Vo IP provider; there is flexibility to have several digit map rules. You can make economical phone calls over the Internet with Vo IP, or over analog phone line or the ISDN line. By adopting hardware-based VPN platform & hardware encryption of AES/DES/3DS, the router increases the performance of VPN greatly, & offers several protocols (such as IPSec/PPTP/L2TP) with up to 32 VPN tunnels. The object-based design used in SPI (Stateful Packet Inspection) firewall allows users to set firewall policy with ease. Object-based firewall is flexible & allows your network be safe. DOS/DDo S prevention & URL/ Web content filter strengthen the security outside & control inside. In addition to the primary ADSL interface, the Vigor 2820 ISDN S0 series let you have additional WAN port for Internet access. The additional WAN port is an Ethernet interface & you can connect it to a second ADSL modem or any other Ethernet-based Internet feed. This secondary WAN port can be used for WAN- backup or load balancing. In case of your primary ISP or ADSL line suf