User Manual Part 2

 Application Layer Gateway (ALG) Configuration: Place a check in appropriate feature boxes to enable them. . Some protocols and

applications require special handling of the IP payload to make them work with network address translation (NAT). Each ALG provides

special handling for a specific protocol or application. A number of ALGs for common applications are enabled by default.

 PPTP: Allows multiple machines on the LAN to connect to their corporate networks using PPTP protocol. When the PPTP ALG is

enabled, LAN computers can establish PPTP VPN connections either with the same or with different VPN servers. When the PPTP

ALG is disabled, the router allows VPN operation in a restricted way -- LAN computers are typically able to establish VPN tunnels to

different VPN Internet servers but not to the same server. The advantage of disabling the PPTP ALG is to increase VPN performance.

Enabling the PPTP ALG also allows incoming VPN connections to a LAN side VPN server (refer to Advanced → Virtual Server).

 IPSec: (VPN) Allows multiple VPN clients to connect to their corporate networks using IPSec. Some VPN clients support traversal of

IPSec through NAT. This option may interfere with the operation of such VPN clients. If you are having trouble connecting with your

corporate network, try disabling this option. Check with the system administrator of your corporate network whether your VPN client

supports NAT traversal.

 RTSP: Allows applications that use Real Time Streaming Protocol to receive streaming media from the internet. QuickTime and Real

Player are some of the common applications using this protocol.

 Windows/MSN Messenger: Supports use on LAN computers of Microsoft Windows Messenger (the Internet messaging client that

ships with Microsoft Windows) and MSN Messenger. The SIP ALG must also be enabled when the Windows Messenger ALG is

enabled.

 FTP: Allows FTP clients and servers to transfer data across NAT.

 H.323 (Netmeeting): Allows H.323 (specifically Microsoft Netmeeting) clients to communicate across NAT server.

 SIP: Allows devices and applications using VoIP (Voice over IP) to communicate across NAT. Some VoIP applications and devices

have the ability to discover NAT devices and work around them. This ALG may interfere with the operation of such devices. If you are

having trouble making VoIP calls, try turning this ALG off.

 Wake-On-LAN: This feature enables forwarding of "magic packets" (that is, specially formatted wake-up packets) from the WAN to a

LAN computer or other device that is "Wake on LAN" (WOL) capable.

 MMS: Allows Windows Media Player, using MMS protocol, to receive streaming media from the internet.

 Click on the Apply button to store these settings.