NodeConnect

I have done a few posts on subnetting and the inner workings of DHCP. I wanted to do a post on IPv6 and a hands-on demo on implementing DHCP on actual networking equipment. However, I missed a few parts that I would like to cover that would particularly help in understanding how IP works and why it is needed. Unlike the previous series, this will be a direct approach to a certain protocol: Internet Protocol (IP). I recently started my first series, covering important ports, protocols, and acronyms used in the networking field. However, I realized not only is it difficult to address the ones to mention, but for some letters it's hard to find. The intended structure was to have several per letter not just one. The idea seemed fun and engaging, however, doing over 20 posts alphabetically on acronyms, ports, and protocols lacks order and deviates from the direct approach I want this blog to have. For that reason, I am putting it on hold indefinitely. It was fun at first, but it was not...

Image created by ChatGPT I recently rewatched an episode of The Art of Network Engineering where hosts Andy Lapteff  and William Collins  interviewed Muna Chimso about his dual experience in networking and programming. In their conversation, Andy asked a thought-provoking question:  "Why doesn't anybody want to go into networking?" It's a valid question. I have met people who struggle with networking, but that's not the point. Many are drawn to other fields: cybersecurity, programming, AI & machine learning, the cloud ... the list goes on. I reflected on the question for myself. What drew me to networking? Here are my 5 answers. Maybe you can relate. 1. Networking is everywhere Everything relies on a network. Think about it: our smartphones, operating systems, and driverless cars all rely on a network for communication. Because it is so pervasive, understanding networking can make troubleshooting quicker and easier. Improving your home network can be exciti...

Visual breakdown of the OSI Model's 7 layers Whether you are new to IT or a seasoned admin, chances are you have heard of the OSI or the TCP/IP model. These frameworks help us understand how data flows across our networks — from online shopping to high-speed data transfers. However, many job postings require knowledge of TCP/IP but not OSI. Why is that? Is one favored over the other? Let's take a look at both. What is the OSI Model?  Introduced in the 1980s, the Open System Interconnect — OSI — breaks down network communication into seven layers, each with a specific function. Layer Functions 7. Application User and device interaction for network services (web browsing, email, file transfer) 6. Presentation Formats data for applications, ensures readable and secure data 5. Session Establishes, maintains, and ends connections between devices. For example: Online shop...

I Passed the Network+ Exam! Here's My Journey I can't believe it. After months and years of practice, patience, and frustration, I am Network+ certified. Even thinking about it gets me excited. The journey here was not easy. Many people have their stories on how they passed, such as what study resources they used, the amount of time spent, sacrifices, or even field experience. I am going to throw my hat in the ring and share my experience, from what I remember, to get here. I'll even include some tips and the resources I used to pass this exam. Discovering Networking Through A+ It started with going into the A+ certification. The hardware sections were overwhelming at first, but I especially enjoyed the parts about cloud computing, virtualization, and networking. Consistently, networking stood out as my best-performing domain. At first, I just needed an introduction to networking, but as time went on—and with the opportunity of getting an internship—the need for the ...

A reservation means nothing if you get the wrong size for your guests, or a party crasher, intended or not, is there first. Similarly, if DHCP is not secure, your device runs the risk of not getting the right network configuration—or any at all. What threats does DHCP face, and how can we protect both devices and the server from such attacks? Let's secure those answers. For a refresher on DHCP, check out this post . DHCP Attacks Rogue DHCP Server On picnic day, you go to the park office to claim your pavilion, but another staff member—different from the one you arranged the event with—has no note of your reservation and gives you another pavilion. What does that mean for your guests? They already have the original location. Things just got complicated. Similarly, a rogue DHCP server is an unauthorized or misconfigured device that disrupts the operations of an authorized server within a network. This can result from manually assigning conflicting IP address ranges or some...

Lab time! Want to build a DHCP server?  In this lab, I will show you how to build your own DHCP server on a router using Cisco Packet Tracer, as shown above. By the end of this post, you will be able to create your own DHCP server with a Cisco 2911 router, perhaps in a home lab setting, and prepare you to build your own on other hardware.  Why a Router?  A DHCP server is a centralized, automated service that assigns important network configuration details to devices on a network, such as IP addresses. Without it, we would have to create manual entries for our entire network, which can be time-consuming and lead to errors. Traditionally, there are dedicated servers to handle these functions. There are many ways to implement a DHCP server in your topology, including a dedicated physical server, a virtual machine, cloud-based gateways, and firewalls. However, there are specific benefits to using a router as your DHCP server: Reduced infrastructure: While havi...

It’s party time! You decide to throw a party at a park with a bunch of pavilions. But you can’t just walk up and claim a pavilion. Instead, you have to go through the park’s reservation service. You tell them the date and time of your event, and they check their list to see what’s available. Great news! A pavilion is open, and they assign it to you for a set time. The day arrives, and as planned, you host your party until it’s time to leave. What a great gathering! This is a lot like how DHCP works in a network. When a device — like your phone or laptop — joins a network, it can’t just start communicating. It needs an IP address first, just like you needed a reserved pavilion. Then, what is the "reservation" process of getting an IP address? Let's take a dive into the automated world of DHCP. What is DHCP? The Dynamic Host Configuration Protocol simplifies network provisioning by automatically assigning important network parameters. These include: IP addresses : Just as ...