Pulling Back the Curtains

14 December 2020 | Comments Off on Pulling Back the Curtains

One of the major sources of complexity in modern systems is the simple failure to pull back the curtains. From a recent blog post over at the ACM—

The Wizard of Oz was a charlatan. You’d be surprised, too, how many programmers don’t understand what’s going on behind the curtain either. Some years ago, I was talking with the CTO of a company, and he asked me to explain what happens when you type a URL into your browser and hit enter. Do you actually know what happens? Think about it for a moment.

Current Work in BGP Security

7 December 2020 |

I’ve been chasing BGP security since before the publication of the soBGP drafts, way back in the early 2000’s (that’s almost 20 years for those who are math challenged). The most recent news largely centers on the RPKI, which is used to ensure the AS originating an advertisements is authorized to do so (or rather “owns” the resource or prefix). If you are not “up” on what the RPKI does, or how it works, you might find this old blog post useful—its actually the tenth post in a ten post series on the topic of BGP security.

The EXPERIENCE HAS SHOWN THAT Keyword (RFC1925, Rule 4)

1 December 2020 |

The world of information technology is filled, often to overflowing, with those who “know better.” For instance, I was recently reading an introduction to networking in a very popular orchestration system that began with the declaration that routing was hard, and therefore this system avoided routing. The document then went on to describe a system of moving packets around using multiple levels of Network Address Translation (NAT) and centrally configured policy-based routing (or filter-based forwarding) that was clearly simpler than the distributed protocols used to run large-scale networks. I thought, for a moment, of writing the author and pointing out the system in question had merely reinvented routing in a rather inefficient and probably broken way, but I relented.

Innovation Myths

30 November 2020 | Comments Off on Innovation Myths

Innovation has gained a sort-of mystical aura in our world. Move fast and break stuff. We recognize and lionize innovators in just about every way possible. The result is a general attitude of innovate or die—if you cannot innovate, then you will not progress in your career or life. Maybe it’s time to take a step back and bust some of the innovation myths created by this near idolization of innovation.

You can’t innovate where you are. Reality: innovation is not tied to a particular place and time. “But I work for an enterprise that only uses vendor gear… Maybe if I worked for a vendor, or was deeply involved in open source…” Innovation isn’t just about building new products! You can innovate by designing a simpler network that meets business needs, or by working with your vendor on testing a potential new product. Ninety percent of innovation is just paying attention to problems, along with a sense of what is “too complex,” or where things might be easier.

The Senior Trap

23 November 2020 | Comments Off on The Senior Trap

How do you become a “senior engineer?” It’s a question I’m asked quite often, actually, and one that deserves a better answer than the one I usually give. Charity recently answered the question in a round-a-bout way in a post discussing the “trap of the premature senior.” She’s responding to an email from someone who is considering leaving a job where they have worked themselves into a senior role. Her advice?

Quit!

Technologies that Didn’t: Asynchronous Transfer Mode

17 November 2020 |

One of the common myths of the networking world is there were no “real” networks before the early days of packet-based networks. As myths go, this is not even a very good myth; the world had very large-scale voice and data networks long before distributed routing, before packet-based switching, and before any of the packet protocols such as IP. I participated in replacing a large scale voice and data network, including hundreds of inverse multiplexers that tied a personnel system together in the middle of the 1980’s. I also installed hundreds of terminal emulation cards in Zenith Z100 and Z150 systems in the same time frame to allow these computers to connect to mainframes and newer minicomputers on the campus.

Casual Dress Considered Harmful?

16 November 2020 | Comments Off on Casual Dress Considered Harmful?

I remember a time long ago—but then again, everything seems like it was “long ago” to me—when I was flying out to see an operator in a financial district. Someone working with the account asked me what I normally wear… which is some sort of button down and black or grey pants in pretty much any situation. Well, I will put on a sport jacket if I’m teaching in some contexts, but still, the black/grey pants and some sort of button down are pretty much a “uniform” for me. The person working on the account asked me if I could please switch to ragged shorts, a t-shirt, and grow a pony tail because … the folks at the operator would never believe I was an engineer if I dressed to “formal.”

Technical Debt (or Is Future Proofing Even a Good Idea?)

9 November 2020 |

What, really, is “technical debt?” It’s tempting to say “anything legacy,” but then why do we need a new phrase to describe “legacy stuff?” Even the prejudice against legacy stuff isn’t all that rational when you think about it. Something that’s old might also just be well-tested, or well-worn but still serviceable. Let’s try another tack.

The Dangers of Flying Pigs (RFC1925, rule 3)

3 November 2020 | Comments Off on The Dangers of Flying Pigs (RFC1925, rule 3)

There are many times in networking history, and in the day-to-day operation of a network, when an engineer has been asked to do what seems to be impossible. Maybe installing a circuit faster than a speeding bullet or flying over tall buildings to make it to a remote site faster than any known form of conveyance short of a transporter beam (which, contrary to what you might see in the movies, has not yet been invented).

Strong Reactions and Complexity

2 November 2020 | Comments Off on Strong Reactions and Complexity

In the realm of network design—especially in the realm of security—we often react so strongly against a perceived threat, or so quickly to solve a perceived problem, that we fail to look for the tradeoffs. If you haven’t found the tradeoffs, you haven’t looked hard enough—or, as Dr. Little says, you have to ask what is gained and what is lost, rather than just what is gained. This failure to look at both sides often results in untold amounts of technical debt and complexity being dumped into network designs (and application implementations), causing outages and failures long after these decisions are made.