TP-LINK TL-WR841ND Benutzerhandbuch

 

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disable the Router’s firewall. 

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SPI Firewall - SPI (Stateful Packet Inspection, also known as dynamic packet filtering) 

helps to prevent cyber attacks by tracking more state per session. It validates that the 

traffic passing through the session conforms to the protocol. SPI Firewall is enabled by 

factory default. If you want all the computers on the LAN exposed to the outside world, 

you can disable it.   

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VPN - VPN Passthrough must be enabled if you want to allow VPN tunnels using IPSec, 

PPTP, or L2TP protocols to pass through the Router’s firewall. 

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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 Router, keep the default, Enabled.  

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L2TP Passthrough - Layer 2 Tunneling Protocol (L2TP) is the method used to enable 

Point-to-Point sessions via the Internet on the Layer 2 level. To allow L2TP tunnels to 

pass through the Router, keep the default, Enabled. 

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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 

Router, keep the default, Enabled. 

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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, H323 etc.   

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FTP ALG - To allow FTP clients and servers to transfer data across NAT, keep the 
default Enable.   

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TFTP ALG - To allow TFTP clients and servers to transfer data across NAT, keep the 
default Enable. 

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H323 ALG - To allow Microsoft NetMeeting clients to communicate across NAT, keep 
the default Enable. 

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RTSP ALG - To allow some media player clients to communicate with some streaming 
media servers across NAT, click Enable.   

Click the Save button to save your settings. 

Choose menu “Security  → Advanced Security”, you can protect the Router from being 

attacked by TCP-SYN Flood, UDP Flood and ICMP-Flood in the screen as shown in Figure 4-40.  

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RTSP ALG - To allow some media player clients to communicate with some streaming media servers 

across NAT, click Enable.