... it supports static and dynamic route,PPP Client and PPP server,VPN client(PPTP,L2TP,IPSEC and GRE)(only ... for VPN version),DHCP server and client,DDNS (dynamic DNS),firewall,NAT and DMZ host. ... -40~+85ºCHumidity: 95% (unfreezing)Software functionSupport VPN client(PPTP,L2TP,IPSEC and GRE)(only for VPN version)Support ... upgrade firmwareSupport multi OS, such as WINDOWS, LINUX, SCO UNIX etc