TP-LINK 1910010885 User Manual

 

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Choose menu “Network”Æ“ALG Settings”, and then you can configure the basic security in the 
screen as shown in Figure 4-23. 

 

 

Figure 4-23 

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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 Passthrough: 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. 

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L2TP Passthrough: 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. 

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IPSec Passthrough: 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. 

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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 
layer "control/data" protocols such as FTP, TFTP etc.   

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FTP ALG: To allow FTP clients and servers to transfer data across NAT, click Enable. 

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TFTP ALG: To allow TFTP clients and servers to transfer data across NAT, click 

Enable. 

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H323 ALG: To allow H323 clients and servers to transfer data across NAT, click 

Enable. 

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SIP ALG: To allow SIP clients and servers to transfer data across NAT, click Enable. 

Click the Save button to save your settings.