Technologies that Didn’t: The Fiber Distributed Data Interface
Token Ring, in its original form, was—on paper—a very capable physical transport. For instance, because of the token passing capabilities, it could make use of more than 90% of the available bandwidth. In contrast, Ethernet systems, particularly early Ethernet systems using a true “single wire” broadcast domain, cannot achieve nearly that kind of utilization—hence “every device on its own switch port.” The Fiber Distributed Data Interface, or FDDI, is like Token Ring in many ways. For instance, FDDI uses a token to determine when a station connected to the ring can transmit, enabling efficient use of bandwidth.
And yet, Ethernet is the common carrier of almost all wired networks today, and even wireless standards mimic Ethernet’s characteristics. What happened to FDDI?
The White Board and the Simulation
In the argument between OSPF and BGP in the data center fabric over at Justin’s blog, I am decidedly in the camp of IS-IS. Rather than lay my reasons out here, however (a topic for another blog post?), I want to focus on something else Justin said that I think is incredibly important for network engineers to understand.
I think whiteboards are the most important tool for network design currently available, which makes me sad. I wish that wasn’t true, I want much better tools. I can’t even tell you the number of disasters averted by 2-3 great network engineers arguing over a whiteboard.
The Hedge 48: Chris Romeo and the State of Security
Chris Romeo is a famous application security expert who has spent the last several years building a consulting and training company called Security Journey. Chris joins Tom and Russ to talk about the state of security and what network engineers need to know about security from an application perspective.
Unsolicited Multicast: Random Thoughts on the LFN White Paper
A short while back, the Linux Foundation (Networking), or LFN, published a white paper about the open source networking ecosystem. Rather than review the paper, or try to find a single theme, I decided to just write down “random thoughts” as I read through it. This is the (rather experimental) result.
Deterministic Networking and New IP
For those not following the current state of the ITU, a proposal has been put forward to (pretty much) reorganize the standards body around “New IP.” Don’t be confused by the name—it’s exactly what it sounds like, a proposal for an entirely new set of transport protocols to replace the current IPv4/IPv6/TCP/QUIC/routing protocol stack nearly 100% of the networks in operation today run on. Ignoring, for the moment, the problem of replacing the entire IP infrastructure, what can we learn from this proposal?
The Hedge 47: Scott Burleigh and the Bundle Protocol
In this episode of the Hedge, Scott Burleigh joins Alvaro Retana and Russ White to discuss the Bundle Protocol, which is designed to support delay tolerant data delivery over intermittently available or “stressed” networks. Examples include interstellar communication, email transmission over networks where access points move around (carrying data with them), etc. You can learn more about delay tolerant networking here, and read the most recent draft specification here.
The 4D Network
I think we can all agree networks have become too complex—and this complexity is a result of the network often becoming the “final dumping ground” of every problem that seems like it might impact more than one system, or everything no-one else can figure out how to solve. It’s rather humorous, in fact, to see a lot of server and application folks sitting around saying “this networking stuff is so complex—let’s design something better and simpler in our bespoke overlay…” and then falling into the same complexity traps as they start facing the real problems of policy and scale.
This complexity cannot be “automated away.” It can be smeared over with intent, but we’re going to find—soon enough—that smearing intent on top of complexity just makes for a dirty kitchen and a sub-standard meal.
The Hedge 46: The Value of a College Degree
While many network engineers think about getting a certification, not many think about going after a degree. Is there value in getting a degree for the network engineer? If so, what is it? What kinds of things do you learn in a degree program for network engineering? Eric Osterweil, a professor at George Mason University, joins Jeremy Filliben and Russ White on this episode of the Hedge to consider degrees for network engineers.
Smart Network or Dumb?
Should the network be dumb or smart? Network vendors have recently focused on making the network as smart as possible because there is a definite feeling that dumb networks are quickly becoming a commodity—and it’s hard to see where and how steep profit margins can be maintained in a commodifying market. Software vendors, on the other hand, have been encroaching on the network space by “building in” overlay network capabilities, especially in virtualization products. VMWare and Docker come immediately to mind; both are either able to, or working towards, running on a plain IP fabric, reducing the number of services provided by the network to a minimum level (of course, I’d have a lot more confidence in these overlay systems if they were a lot smarter about routing … but I’ll leave that alone for the moment).
How can this question be answered? One way is to think through what sorts of things need to be done in processing packets, and then think through where it makes most sense to do those things. Another way is to measure the accuracy or speed at which some of these “packet processing things” can be done so you can decide in a more empirical way. The paper I’m looking at today, by Anirudh et al., takes both of these paths in order to create a baseline “rule of thumb” about where to place packet processing functionality in a network.
The Hedge 45: When to Quit Certifications
Certifications are a perennial topic (like weeds, perhaps) in the world of network engineering. While we often ask whether you should get a certification or a degree, or whether you should get a certification at all, we don’t often ask—now that you have the certification, how long should you keep it? Do you keep recertifying “forever,” or is there a limit? Join us as Mike Bolitho, Eyvonne Sharp, Tom Ammon, and Russ White discuss when you should give up on that certification.