TD-8840T ADSL2+ Modem Router User Guide
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Figure 4-13
) Note:
Only the WAN Ports can use MAC Address Clone function. All the clone MAC addresses must not
be the same with each other.
4.4.5 ALG Settings Choose menu “Advanced Setup”Æ“ALG Settings”, and then you can configure the basic
security in the screen as shown in Figure 4-14.
Figure 4-14
¾ Virtual Private Network (VPN) - VPN Passthrough must be enabled if you want to allow VPN
tunnels using VPN protocols to pass through the Modem Router.
• PPTP Pass-through - Point-to-Point Tunneling Protocol (PPTP) allows the
Point-to-Point Protocol (PPP) to be tunneled through an IP network. To allow PPTP
tunnels to pass through the Modem Router, click Enable.
• L2TP Pass-through - Layer Two Tunneling Protocol (L2TP) is the method used to
enable Point-to-Point sessions via the Internet on the Layer Two level. To allow L2TP
tunnels to pass through the Modem Router, click Enable.
• IPSec Pass-through - Internet Protocol security (IPSec) is a suite of protocols for
ensuring private, secure communications over Internet Protocol (IP) networks, through
the use of cryptographic security services. To allow IPSec tunnels to pass through the
Modem Router, click Enable.
¾ Application Layer Gateway (ALG) - It is recommended to enable Application Layer Gateway
(ALG) because ALG allows customized Network Address Translation (NAT) traversal filters to
be plugged into the gateway to support address and port translation for certain application