What To Do When Your Network Decided to Ghost Itself

 

Your switch port is sitting there in Discarding state like it's on a bad date—totally up physically, link lights are happy, but it's refusing to pass any traffic. In modern speak (especially with Rapid Spanning Tree Protocol, aka RSTP), "discarding" is the cool new name for the old-school "blocking" state. The switch isn't broken; it's just being dramatically cautious. Think of it as the network's overprotective parent yelling "NOPE" to prevent total chaos.

From thenetworkdna - AAA Concepts

 

AAA Concepts: Authentication, Authorization, and Accounting

The article introduces the essential AAA framework—Authentication, Authorization, and Accounting—as a foundational model for modern network security and access control. Rather than relying on basic, device-specific passwords, AAA offers a scalable, centralized approach to managing who can access systems, what they can do once authenticated, and how their actions are recorded for audit or billing purposes. By clearly defining and separating these three functions, organizations can establish stronger security policies while maintaining detailed records of user activity.

Why Is Your ‘Gigabit’ Port Is Only Doing 100 Mbps

The first time i saw this switch , all sort of red flags shot up in my head. Do you see the issue here? I will give you a hint; the devices are all new (1 Gb ethernet), the switch has 1 Gb ethernet ports.

Ok here goes my rant....

You pay for gigabit. You bought the gigabit switch. The box literally says Gigabit Ethernet in bold, confident letters. And yet… your port is humming along at a very 2005-looking 100 Mbps. What gives? Before you start blaming your computer, your switch, or Mercury being in retrograde, take a breath — there are a handful of very common reasons your link decided to downshift.

The usual suspect? Cabling. Gigabit Ethernet needs all four twisted pairs inside that cable to work properly. Fast Ethernet (100 Mbps) only needs two. So if one pair is damaged, poorly crimped, bent, or simply missing (looking at you, mystery wall jack), the link will politely negotiate down to 100 Mbps and call it a day. A quick cable swap with a known-good Cat5e or Cat6 cable solves this more often than anyone likes to admit.

Basics of Wireshark – Session 1 – Setting up your Wireshark Install

 The “Basics of Wireshark – Session 1: Setting Up Your Wireshark Install” article on InfoSecMonkey walks beginners through everything needed to get started with one of the most powerful network protocol analyzers available today. It begins with clear, accessible guidance on how to download and install Wireshark—whether you’re on Windows, macOS, or Linux—and ensures you understand the essential options and components that make the installation successful. By following this session, even those new to network analysis will gain confidence installing the software and preparing it for real-world use.

Capture DHCP packets to get a lease on your troubleshooting life

Ever feel like your network just decides not to work? That’s usually DHCP quietly causing chaos behind the scenes. Capturing DHCP packets is like eavesdropping on the most important conversation happening on your LAN. You get to watch the full DORA process — Discover, Offer, Request, Acknowledge — play out in real time. Is the client yelling “Anybody got an IP?” and getting ghosted? Is the server offering an address that never gets accepted? A quick packet capture tells the story faster than any guesswork ever could.