New answers tagged

0

You are causing the packets sent by PC2 to have the correct destination port but not the correct source port. To be viewed as a reply packet, both the destination port and source port have to match. For example, say PC1's external address is 1.1.1.1 and PC2's external address is 2.2.2.2. When you send HTTP requests from PC1 to PC2, the source address will be ...


1

STUN not supporting symmetric NAT is not a question of modern vs. not modern but how NAT and STUN is working. STUN is about predicting which port will be used for a connection to IP address X (out of control of STUN server) from looking at previous connections to IP addresses in control of the STUN server. The very description of what symmetric NAT is means, ...


1

End to end direct connectivity means implementing IPv6. NATs and address conflicts are then obsolete. With IPv4, making NAT traversal work is more complicated. Relays, hole punching, proxies, or tunnels are the primary categories of implementation. But which to use specific to the network and the application. All that can be said with the information you ...


0

In the meantime I learned that one CAN mark packets (see, e.g., How to set mark on packet when forwarding it in nat prerouting table?), and also learned more about which iptables operations are applied when (https://www.digitalocean.com/community/tutorials/a-deep-dive-into-iptables-and-netfilter-architecture). With these the solution is straightforward: in /...


0

You can skip the dummy interface and REDIRECT such traffic to the localhost IP address. In the nat table: -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-ports 8080 Then you tell ufw to allow traffic to that port, but only destined to the localhost IP address. sudo ufw allow to 127.0.0.1 port 8080 proto tcp


0

So I have had the opportunity to thoroughly test this "NAT type" terminology in (broadly) two networking environments. MikroTik's RouterOS v6 was used to conduct this test and hence I will use MikroTik networking terminologies. Before we begin I will assume you know the basics of: NAT (including PAT which essentially is just "NAT" in ...


Top 50 recent answers are included