CCDE

My CCDE Journey — Background, Preparation, Study Strategy, Courses, and Practice Exams

My CCDE Journey

Earning my CCDE certification (CCDE 2026::37) was one of the hardest things I have done in my professional life. Not because the topics are impossibly complex, but because the exam requires a depth and breadth of design knowledge that takes real time and effort to build. And also because, at 52, learning takes longer than it did at 30.

This article is a candid description of my journey to get there: two attempts at the written exam, three attempts at the practical exam, two bootcamps, a LOT of reading and perseverance.

CCDE Reading List

CCDE Reading List

One of the most common questions I get from CCDE candidates is: “What should I read?” and “Where should I start?”
This post is the CCDE reading list I actually used to pass the CCDE written (400-007) and practical exams. I have organized everything into my O’Reilly playlist, publicly accessible, so you can follow it directly if you have an O’Reilly subscription.

This list includes full books, individual chapters, and video courses. Some chapters were selected for their specific content, while the video courses provide a complementary perspective on subjects covered in the books.

CCDE Tips

CCDE Practical Exam — Tips and Tricks for Exam Day

I recently passed the CCDE practical exam at Cisco Live. I am now CCDE #2026::37. During my preparation, I gathered insights from fellow candidates, seasoned CCDEs, and instructors, including Zig Zsiga, Russ White, Orhan Ergun, Mark Holm, and others. I combined them with my own experience on exam day: it took me three attempts to pass, so I have some experience. This post is my attempt to distill all of that into a practical guide for anyone sitting for the CCDE lab.

Scale-up, Scale-out, Scale-across

Understanding Scale-Out, Scale-Up, and Scale-Across Networking

Modern AI and HPC workloads place extraordinary demands on the underlying network infrastructure. And as network engineers, we are often pulled into conversations about GPU clusters, maybe without a clear map of the terrain.

Three terms come up constantly: scale-out, scale-up, and scale-across networking.

They describe fundamentally different network constraints and requirements. Here is a brief and simple explanation of each.

Cisco Live

Cisco Live means human connectivity

Why You Should Attend Cisco Live — and Actually Talk to People

Back in 2022, I wrote a post covering everything Cisco Live has to offer: the technical sessions, the labs, the World of Solutions, and the various events. I ended it with a small remark: “Above all, interact with people, make new contacts, and participate in discussions”. I still think it’s the most underrated piece of advice I could give. This year will be my 13th Cisco Live, and if anything, I believe it more firmly now than ever.

Cisco Live 2024 Wrap-Up – Cisco Nexus HyperFabric, Disaggregated Scheduled Fabric (DSF) and SONiC

Cisco Live 2024 Wrap-Up – Cisco Nexus HyperFabric, Disaggregated Scheduled Fabric (DSF) and SONiC

Last week, I attended my 11th Cisco Live in person, in the fabulous Las Vegas. This post is my Cisco Live 2024 Wrap-up.

I can already tell you that the next edition of Cisco Live US will be held June 8-12, 2025 in San Diego, California. If my company agrees to send me there, I’m already looking forward to it, because San Diego is a wonderful city.

The Future of Network Engineering in the AI/ML era

The Future of Network Engineering in the AI/ML era

It seems like yesterday when I saw my first network automation presentation at a conference. I remember it very well; it was in 2015 at the Cisco Network Innovation Summit in Prague. Mr. Tim Szigeti was presenting the first version of the Cisco APIC-EM, the future Cisco Digital Network Architecture (DNA) controller. I talked already about it in a previous article, written in 2018, about my journey toward network programmability and automation.

After its presentation, and for many years afterward, the question was on everyone’s lips: