Some devices need to access the internet from another country but cannot run a VPN client or control routing. In such cases, software solutions are not enough. A hardware gateway becomes the only reliable way to enforce traffic routing without modifying the client itself.

In this article, I show how to turn a Raspberry Pi into a fully autonomous VPN gateway using Tailscale Exit Nodes. The setup integrates into an existing Tailscale infrastructure, prevents DNS leaks, blocks VPN bypass, and works even behind CGNAT. The client device remains completely unaware of the VPN, while all its traffic exits through the required country.

Sometimes you just need a simple tool that works. udp_redirect is a tiny utility for redirecting UDP packets to another destination and sending responses back to the original sender. No iptables, no FIFO files, no pipes, no additional dependencies – just a single C file and a working binary.

I used it to redirect OpenVPN UDP traffic in order to hide the real IP address, and it turned out to be one of the simplest and most reliable solutions for quick UDP forwarding.

The tool listens on a given IP and port, forwards incoming packets to a specified destination, and remembers the sender's address. When a response comes back, it is sent to the original sender. This behavior is very similar to how symmetric NAT works.

There is also an echo mode, where all received packets are sent back to the sender, which is useful for testing and debugging.

The utility was originally used to test VoIP tools by looping RTP ports, but it can be handy in many networking and testing scenarios.

Non-routable IPv4 addresses appear everywhere: in private networks, VPNs, NAT setups, ISP infrastructure, and test environments – yet their purpose is often misunderstood.

This article provides a clear, RFC-based overview of non-routable IPv4 ranges, including private address space (RFC1918), CGNAT, loopback, link-local addressing, multicast, documentation networks, and reserved blocks. Real-world scenarios such as NAT and VPN usage are covered without unnecessary theory.

Modern distributed systems rarely operate in perfect network environments. Unstable Wi-Fi, overloaded routers, mobile links, and long WAN routes can easily break even well-designed applications. To understand how a service behaves under such conditions, QA teams must simulate real-world network degradation during testing.

Clumsy is a Windows-based tool that intercepts and manipulates network packets on the fly, allowing testers to reproduce latency, packet loss, duplication, reordering, corruption, and bandwidth limits without modifying application code. Built on top of the WinDivert driver, it affects traffic system-wide and makes it possible to validate client-server behavior in scenarios that are difficult to reproduce naturally.

Wireshark remains one of the most trusted tools for network engineers, security teams, and integrators – and its true power comes from display filters that instantly cut through noisy packet captures.

From DHCP and ARP discovery to HTTP inspection and multicast debugging, the article provides practical, ready-to-use filters that engineers rely on every day. Whether you're troubleshooting a camera, analyzing DNS, or tracking HTTPS flows, these filters will dramatically speed up your Wireshark workflow.