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Post Views: 4,821 The links to the products shown here are all available through Amazon, and if you use these links, we will get a small cut through our Amazon Associates program without affecting the price you pay. We thank you for doing this. You can also check out my Amazon Storefront here. I often […]
The Network Products We Use in Our “Go Bag” Read More »
Post Views: 18,225 Signal-to-Noise Ratio (SNR) is a measure of how strong a signal is compared to the background noise in a communication system. It is typically expressed in decibels (dB). The higher the SNR, the clearer and more reliable the signal. I often get asked, how is signal to noise calculated. Frankly the math
The Signal to Noise Ratio (SNR) Calculation Read More »
Post Views: 5,544 A great question in my two day Security class recently. The physical layer (Layer 1) of the layered model is responsible for the transmission of raw data bits over a communication medium. Although it is often considered more secure due to its reliance on physical components, it is still vulnerable to a
What are some examples of Physical Layer Threats in Networking? Read More »
Post Views: 2,270 I am getting asked a lot about this. Below is mix of reporting and my take on what happened and what needs to be done. Just so we are clear: I have no secret inside knowledge or insight into the problems. But if you are looking for a clear explanation, read on.
What was the nature of the July 2024 CrowdStrike computer outages? Read More »
Post Views: 4,068 Network Address Translation (NAT) and Network Port Address Translation (NPAT) are not considered a security function because its primary purpose is to modify the L3 network address information in IPv4 packet headers and L4 port numbers of TCP or UDP while in transit. NAT and NPAT are not needed in IPv6 networking.
Why are NAT/NPAT not a security function? Read More »
Post Views: 3,896 Are you new to Wireshark? Someone asked the following “getting started” question on the Wireshark Discord site, and it prompted me to write this FAQ to help newcomers to Wireshark understand how to navigate the initial complexity of packet capture. Hi everyone! I’m new here and just downloaded wireshark for a Computer
A Simple Capture and Filter Exercise for Wireshark Read More »
Post Views: 8,404 Asynchronous Transfer Mode (ATM) was once seen as a promising Layer 2 networking technology due to its ability to handle a variety of traffic types (voice, video, and data) with high efficiency and quality of service (QoS) performance guarantees. I spent several years working with and then teaching ATM courses to my
What ever happened to ATM (Asynchronous Transfer Mode)? Read More »
Post Views: 2,479 As always seems to be the case, there are several ways to find the MAC (Media Access Control) address of your interfaces in Windows. I am going to try to make this easy and considerate of different versions of Windows out there. Using the Command Line To find the Windows MAC address
How do I find my PC’s MAC address on Windows? Read More »
Post Views: 4,183 I am often asked this question of where to access PCAP or PCAP-NG files so that folks can explore packet captures using Wireshark. I have always provided these resources in my Wireshark classes at the Online School, but thought I should also just list them here for public consumption. Look up the
Where can I get PCAP Packet Captures for Learning and Exploration? Read More »
Post Views: 3,699 How do I install / upgrade Wireshark in Ubuntu Linux? First things first – the Wireshark downloads page is here: https://www.wireshark.org/download.html I know I have put the answer to this in other articles over the years (like this one), but I think it is appropriate to answer the question directly and specifically.
How do I install / upgrade Wireshark in Ubuntu Linux? Read More »
Post Views: 1,716 Check out these great references as well: Our custom profiles repository for Wireshark Our Udemy course on Wireshark Our Udemy course on Wireless Packet capture Apparently this is a common problem, where on Windows systems you do not see any interfaces: There are a couple of things to try: 1. If you
How do I get Windows interfaces to show up in Wireshark? Read More »
Post Views: 1,332 If you would like a definition of what Net Neutrality is and where it stands in the US – look here. If you are a networking geek and want to experiment with Net Neutrality using Wireshark – look here.
Want to understand Net Neutrality? Like burgers? This will explain… Read More »
Post Views: 1,949 I was recently (this was 2017) asked the question “If I want to get into Networking, what should I learn?” If you want to see the 2025 answer – click here. A great question because Telecommunications or Data Networking is really not a degree program at most universities, at least not at
If I want to get into Networking, what should I learn? Read More »
Post Views: 1,761 This question (really two questions) has been popping up quite a bit lately. Let me see if I can explain. First, let’s define what SD-WAN is. SD-WAN leverages the SDN concept of separating the control plane from the data plane and creating a controller running software that can enact control and policies
What is SD-WAN? Does it replace MPLS? Read More »
Post Views: 1,222 This is a great question, and there is a building pile of learning SDN courses out there. Perhaps the most technical one we found, we loved, and thanks to the great folks at Georgia Tech, the lectures were placed in the public domain. We assembled those video lectures and added our own
Where can I learn SDN? Read More »
