User's Manual

Chapter 3: Connections and setup
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Illustrations contained in this document are for representation only.
IPsec PassThrough enables IPsec type packets to pass between WAN and LAN. IPsec (IP Security) is a
security mechanism used in Virtual Private Networks (VPNs).
PPTP PassThrough enables PPTP type packets to pass between WAN and LAN. PPTP (Point to Point
Tunneling Protocol) is another mechanism sometimes used in VPNs.
Remote Config Management makes the configuration web pages in your gateway accessible from the
WAN side. Note that page access is limited to only those who know the gateway access password. When
accessing your gateway from a remote location, your must use HTTP port 8080 and the WAN IP address
of the gateway. e.g., if the WAN IP address is 157.254.5.7, you would navigate to
http://157.254.5.7:8080 to reach your gateway.
Multicast Enable enables multicast traffic to pass through WAN and LAN. You may need to enable this
to see some types of broadcast streaming and content on the Internet.
UPnP Universal Plug and Play (UPnP) helps devices, such as Internet appliances and computers, access
the network and connect to other devices as needed. UPnP devices can automatically discover the
services from other registered UPnP devices on the network.
NAT ALG enable NAT ALG (application layer gateways) allows customized NAT traversal filters to be
plugged into the gateway to support address and port translation for certain application layer
"control/data" protocols such as RSVP, FTP, TFTP, Kerb88, NetBios , IKE, RTSP, Kerb1293 , H225 , PPTP ,
MSN , SIP , ICQ , IRC666x , ICQTalk , Net2Phone , IRC7000 , IRC8000 file transfer in IM applications etc. In
order for these protocols to work through NAT or a firewall, either the application has to know about an
address/port number combination that allows incoming packets, or the NAT has to monitor the control
traffic and open up port mappings (firewall pinhole) dynamically as required. Legitimate application data
can thus be passed through the security checks of the firewall or NAT that would have otherwise
restricted the traffic for not meeting its limited filter criteria.