Iljitsch van Beijnum
Iljitsch's Two Decades with BGP and NL-ix
Who is NL-ix?
Behind the world of the Internet, behind the world of fibers, protocols, peers, and terabytes, are actual people making it all work. But who are these people? In other words: Who is NL-ix?
Today: 🤝 Iljitsch van Beijnum, BGP instructor for NL-ix
Meet Iljitsch van Beijnum: the trusted BGP instructor for NL-ix, delivering specialized Border Gateway Protocol training to NL-ix for over two decades. As a network engineer, network architect, technical writer, programmer, and protocol designer, (the list goes on!) Iljitsch brings extensive expertise to his training sessions, having literally written the book on BGP. His long-standing partnership with NL-ix has helped countless network professionals understand the critical protocol that keeps the Internet connected. We're delighted to have him share his story.
It all began in 1995 when I was an informatics student interning at an Internet provider called XS4ALL. Those were the early days of the Internet in the Netherlands – small Internet providers were popping up everywhere because you needed to dial a local number with your modem to avoid expensive phone bills.
One day, a provider in The Hague called XS4ALL with network problems. The director said, "We can't send our system administrator because if he leaves, our entire network will crash. But we have an intern from The Hague – he'll do." That intern was me.
When I arrived at their office, I discovered they had two connections to the Internet – one extremely slow and one slightly less slow by today's standards. Interestingly, all their traffic was flowing through the slower connection. After some tinkering, I managed to redirect the traffic to the faster connection. By the time I left that evening, their network was running four times faster. They offered me a job on the spot.
It didn't take long for me to realize that when you have two or more connections to the Internet, you need something called BGP to manage them efficiently. I was sent to a room behind a hip-hop record store where there was a Cisco device with a shelf full of instruction manuals. "Set up BGP, figure it out," they told me. And that's how my journey with BGP began.
Writing the book on BGP
After working with several Internet providers and eventually starting my own business in 2000, I realized that when I was learning BGP, I could have really used a good book. So I thought, "Why not write it myself?"
I contacted O'Reilly, the well-known technical book publisher. After some back-and-forth emails, they agreed to publish my book, which came out in 2002.
Around this time, I already knew Jan, Mischa, and Vincent who had formed NL-ix. They contacted me saying, "Hey, the people who connect to NL-ix need to understand BGP. You wrote the book on BGP – why don't you give a course?" The idea was that if we'd do it once or twice, everyone would understand what BGP is, and then we'd be done.
Here we are, hundreds of participants later, still going strong. What was supposed to be a one-time thing has turned into a two-decade relationship.
The surprising stability of Internet protocols
What's fascinating is how little BGP has changed over the decades. Version 3 was released in the early '90s and was already quite close to what we use today. After a BGP crisis, version 4 was quickly released in 1994, and we're still using version 4 to this day.
The protocol has been extended to handle new technologies like IPv6, but the core remains largely unchanged. It's not that there haven't been improvements – it's just that any change requires worldwide consensus, which is incredibly difficult to achieve.
Evolution of the training environment
Some things do change. For example, the way I deliver BGP training has very clearly changed over the years. We started with physical Cisco routers that we'd transport to the training location. I remember Jan's nice car sinking closer to the road with the weight of five large routers in the trunk!
As technology changed, so did our approach. We moved from connecting laptops to routers via serial ports to using Ethernet connections. Now, as laptops have become more security-hardened and often lack Ethernet ports altogether, I'm developing a web-based virtual environment for the practicals.
Despite these changes in delivery, the fundamentals remain constant – the first half of my BGP course has stayed nearly identical for 22 years.
Knowing BGP inside and out
What I love most about my work is solving problems and learning new things. With BGP specifically, I've reached a level of expertise where I can confidently answer any question that comes up in training.
The field stays interesting because there are always new challenges. For instance, I'm currently working on a new course about BGP security for NL-ix.
I've also written a new e-book that focuses on modern BGP practices. I'm planning to create a print-on-demand version as well.
The basics of BGP may not have changed much in 30 years, but the world around it certainly has – and that keeps things interesting.
It's remarkable the Internet works, still
What's remarkable about the Internet is how well it works despite its imperfections. The original design's simplicity allowed for extraordinary growth at reasonable cost. Problems get solved gradually, not quickly, because the entire world needs to agree on changes.
That's perhaps the greatest challenge – getting global consensus to implement better solutions. We often end up with the smallest common denominator rather than the optimal technical solution. But despite this, the Internet continues to grow and evolve, connecting more people and devices every day.
After more than two decades of working with BGP and training NL-ix clients, I'm still finding new challenges and enjoying the opportunity to share my knowledge. The Internet may have changed dramatically since I started in this field, but the need to understand how it all connects remains constant – and that's where I come in.