Firewall - Teltonika RUT750 LTE User Manual

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Firewall

In this section we will look over the various firewall features that come with the router.
General Settings
The routers firewall is a standard linux iptables package, which uses routing chains and policies to facilitate control over
inbound and outbound traffic.
Field name
1. Enable SYN-flood
protection
2. Drop Invalid packets
3. Input
4. Output
5. Forward
*DEFAULT: When a packet goes through a firewall chain it is matched against all the rules for that specific chain. If no
rule matches said packet, an according Action (either Drop or Reject or Accept) is performed.
Accept – Packet gets to continue down the next chain.
Drop – Packet is stopped and deleted.
Reject – Packet is stopped, deleted and, differently from Drop, an ICMP packet containing a message of rejection is sent
to the source of the dropped packet.
Sample value Explanation
Checked/Unchecked When checked the router becomes more resistant against SYN-
flood attacks.
Checked/Unchecked A "Drop" action is performed on a packet that is determined to be
invalid
Reject/Drop/Accept DEFAULT* action that is to be performed for packets that pass
through the Input chain.
Reject/Drop/Accept DEFAULT* action that is to be performed for packets that pass
through the Output chain.
Reject/Drop/Accept DEFAULT* action that is to be performed for packets that pass
through the Forward chain.
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