N Is For Networking

Copper twisted pair cabling serves as a fundamental component of Ethernet infrastructure and Ethan and Holly are here to break down how it works. They discuss the technical differences between cabling categories, how wire twisting cancels out electromagnetic interference, and share practical guidance on installation standards and testing methodologies. Episode Links: Watch this episode on ... Read...

In this sponsored episode by Cisco we explore how agentic AI is transforming network operations and what it means for your career. Robert Barton, an AI Distinguished Engineer at Cisco Systems, joins Ethan and Holly to help us snap the artificial intelligence puzzle piece into your networking picture. Together they break down the AI trifecta: ... Read more »

As a network engineer, you’ll end up with a lot of weird problems to solve. Many times, the problems will not be with the network at all, and it’ll be up to you to figure it all out. But how? Ethan and Holly discuss techniques for effective troubleshooting. Those techniques include how to gather accurate ... Read more »

In the previous episode of N is for Networking, Jennifer “JJ” Jabbusch gave us a thorough overview of Network Access Control (NAC) for wired networks. This week we’re going wireless! JJ walks us through the major differences between wired and wireless NAC, how 802.1X is more seamless in Wi-Fi deployments, the unpredictability of web portals, ... Read more »

Today’s topic is Network Access Control (NAC) for a wired network. To help walk us through it all is Jennifer “JJ” Jabbusch, a network security architect, public speaker, book author, and co-host of the Packet Protector podcast. JJ and our hosts break down the terms and protocols behind NAC, and explain why the architecture was ... Read more »

Today’s episode is part one of a three part series to break down Network Access Control (NAC). Ethan and Holly start simple by explaining what NAC is at a high level and all of the jargon and acronyms that come with it. They also cover where and when network access control is applied, whether NAC ... Read more »

We asked for follow ups and you did not disappoint! On today’s show we respond to listener comments and corrections on multicast, routing protocols, security, and more. We also have a technical correction for the RFC 1918 Class B private address range. A big thank you to everyone who sent in responses. If you’d like ... Read more »

Lenny Giuliano, Sr. Distinguished Systems Engineer at HPE Juniper Networks, joins Holly and Ethan for another round of multicast. Part two helps fill in details not covered in episode 50. They cover how multicast traffic also affects Ethernet frame addressing, and the key differences between IPv4 and IPv6 multicast. They also explain new hybrid multicast ... Read more »

Today’s topic is Multiprotocol Label Switching or MPLS, a foundational technology that powers service provider networks and enterprise WANs all over the world. To help us break it down, we’ve invited James Bensley, a Network Tech Lead who’s spent fifteen years with MPLS. James explains what spurred the creation of MPLS and how it works ... Read more »

Today’s learning adventure is an overview of multicast. Ethan and Holly have invited a guest to share his multicast expertise: Lenny Giuliano, Sr. Distinguished Systems Engineer at HPE Juniper Networks. Lenny guides them through multicast principles and shares examples of where and how it’s used in live networks. He also explains how the OSPF routing ... Read more »

Today, Ethan and Holly provide an overview of firewalls. While cybersecurity is a separate discipline from network engineering, much of what happens in cybersecurity is interesting at the packet level, so there’s a good deal of overlap. It’s likely that as a network engineer, you’ll be managing, or at least dealing with, firewalls in your ... Read more »

Quality of Service (QoS) is a huge topic with a punishingly large group of acronyms. Join Ethan and Holly as they help you build a mental framework of what QoS is and what it solves. Not only do they break down essential acronyms, they also discuss QoS fundamentals, define the major groups of QoS tools, ... Read more »

Go beyond the basics to understand the mechanics that keep your default gateway from becoming a single point of failure. Ethan and Holly demystify Virtual Router Redundancy Protocol (VRRP), which helps provide network redundancy. They break down everything from the VRRP election protocol to the protocol’s unique communication methods. They also look back at previous ... Read more »

Ethan and Holly discuss the major differences between In-band and Out-of-band (OOB) management and the pros and cons of both. They explore how to implement a proper OOB network and critical use cases where OOB is required. They also explain the differences and roles of the data plane, the control plane, and the management plane. ... Read more »

If you’re curious as to what Ethan and Holly have in store for 2026, they give you a sneak peak on today’s episode. Hint: Some of these topics might include letters like B, G, P, Q, o, S, A and I.  They also take time in this episode to answer listener questions, ranging from how ... Read more »

In Part 1 of Redundancy vs. High Availability, we said that sometimes high availability and redundancy are considered to be the same thing, but we disagree. Holly and Ethan do agree that high availability can be considered a network design goal, and that redundancy is just one technique that can be used to help make ... Read more »

In today’s chat, Holly and Ethan consider a question from listener Douglas who asks, “How do you approach designing a network for high availability and redundancy?” They start by defining differences between redundancy and high availability, and talk about Holly’s experience with her own customers. Then they share examples of how to achieve redundancy in ... Read more »

MACsec is a protocol for encrypting Ethernet frames on a local (though not always local) network. Ethan Banks and Holly Metlitzky have an ELI5 (explain like I’m 5) discussion as to what exactly is MACsec and how it differs from IPsec. They talk about when and whether you need to implement MACsec with all the ... Read more »

If you’ve ever wondered what the difference is between a Switched Virtual Interface (SVI) and Integrated Routing and Bridging (IRB), today’s show is for you! Ethan Banks and Holly Metlitzky start with some history and the basics of communication between layer 2 and layer 3 and then explain how the concepts of SVI and IRB ... Read more »

The job interview is an inescapable part of a career journey. Today on N Is For Networking, we conduct a mock interview with a candidate who’s applying for a junior network administration role. The goal is to give Toni Mrowetz, our candidate, feedback. At the same time, we hope this helps anyone listening who might ... Read more »

We dive back into the world of IPsec with an episode dedicated to configuring IPsec tunnels. After discussing a listener comment regarding transport mode in IPsec tunnels, Ethan Banks and Holly Metlitzky work through topics such as multi-vendor IPsec configuration, licensing, and the details of configuration and routing. Bonus material: MTU size and NAT-T. Episode ... Read more »

We got some interesting listener feedback from our series on OSPF, so today’s N Is for Networking is another “Well actually” episode where we dig into that feedback. In particular, we’ll cover a defense of OSPF multi-area deployments, and dig into OSPF LSA types. Episode Links: OSPF Basics – N Is For Networking Episode 38 ... Read more »

It’s time to talk crypto. No, not the Bitcoin kind. Ethan and Holly introduce the basics of IPsec, the protocol that authenticates and encrypts traffic between endpoints. They discuss what it is, how it provides trustworthiness and secrecy to IP traffic, and common use cases. They review the different types of IPsec protocols and modes, ... Read more »

Ethan and Holly bring you the last installment of the OSPF series discussing OSPF area types. They discuss why OSPF areas exist, do a quick recap of what OSPF areas actually are, and then introduce the different types of OSPF areas.  Lastly, see if you can answer Ethan’s rapid-fire OSPF questions. Episode Transcript: This episode ... Read more »

We ask listeners for follow up and you’ve sent it in. On today’s show we respond to listener comments and corrections on tunneling, the link aggregation control protocol, link aggregation in general, and DHCP options. We also talk about the network engineering certification journey. If you’ve got a “Well, actually” or any other follow up, ... Read more »