Dealing with Lock-In
A post on Martin Fowler’s blog this week started me thinking about lock-in—building a system that only allows you to purchase components from a single vendor so long as the system is running. The point of Martin’s piece is that lock-in exists in all systems, even open source, and hence you need to look at lock-in as a set of tradeoffs, rather than always being a negative outcome. Given that lock-in is a tradeoff, and that lock-in can happen regardless of the systems you decide to deploy, I want to go back to one of the foundational points Martin makes in his post and think about avoiding lock-in a little differently than just choosing between open source and vendor-based solutions.
If cannot avoid lock-in either by choosing a vendor-based solution or by choosing open source, then you have two choices. The first is to just give up and live with the results of lock-in. In fact, I have worked with a lot of companies who have done just this—they have accepted that lock-in is just a part of building networks, that lock-in results in a good transfer of risk to the vendor from the operator, or that lock-in results in a system that is easier to deploy and manage.
Giving in to lock-in, though, does not seem like a good idea on the surface, because architecture is about creating opportunity. If you cannot avoid lock-in and yet lock-in is antithetical to good architecture, what are your other options?
(Effective) Habits of the Network Expert
For any field of study, there are some mental habits that will make you an expert over time. Whether you are an infrastructure architect, a network designer, or a network reliability engineer, what are the habits of mind those involved in the building and operation of networks follow that mark out expertise?
Experts involve the user
Experts don’t just listen to the user, they involve the user. This means taking the time to teach the developer or application owner how their applications interact with the network, showing them how their applications either simplify or complicate the network, and the impact of these decisions on the overall network.
Experts think about data
Rather than applications. What does the data look like? How does the business use the data? Where does the data need to be, when does it need to be there, how often does it need to go, and what is the cost of moving it? What might be in the data that can be harmful? How can I protect the data while at rest and in flight?
IPv6 Backscatter and Address Space Scanning
Backscatter is often used to detect various kinds of attacks, but how does it work? The paper under review today, Who Knocks at the IPv6 Door, explains backscatter usage in IPv4, and examines how effectively this technique might be used to detect scanning of IPv6 addresses, as well. Scanning the IPv6 address space is much more difficult because there are 2128 addresses rather than 232. The paper under review here is one of the first attempts to understand backscatter in the IPv6 address space, which can lead to a better understanding of the ways in which IPv6 scanners are optimizing their search through the larger address space, and also to begin understanding how backscatter can be used in IPv6 for many of the same purposes as it is in IPv4.
Kensuke Fukuda and John Heidemann. 2018. Who Knocks at the IPv6 Door?: Detecting IPv6 Scanning. In Proceedings of the Internet Measurement Conference 2018 (IMC ’18). ACM, New York, NY, USA, 231-237. DOI: https://doi.org/10.1145/3278532.3278553
The Hedge 9: Nash King and Ethics in IT
Nash King (@gammacapricorni) joins Russ White and Tom Ammon in a wide ranging discussion of ethics in IT, including being comfortable with standing up and saying “no” when asked to do something you consider unethical and the virtue ethic. This is meant to be the first of a series of episodes on this topic.
SDN, AI, and DevOps
According to the recent SONAR report, 52% of respondents reported they are using Software Defined Networking (SDN) tools to automate their networks, while 57% reported they are using network management tools. The report notes “52% may be slightly exaggerated, depending on how one defines SDN…” Which leads naturally to the question—what the difference between SDN and DevOps is, and how does AI figure into both or either of these. SDN, DevOps, and AI describe separate and overlapping movements in the design, deployment, and management of networks. While they are easy to confuse, they have three different origins and meanings.
Software Defined Networking grew out of research efforts to build and deploy experimental control planes, either distributed or centralized. SDN, however, quickly became associated with replacing some or all the functions of a distributed control plane with a centralized controller, particularly in order to centralize policy related to the control plane such as traffic engineering. SDN solutions always work through a programmatic interface designed to primarily supply forwarding information to network devices.
The Hedge 8: Open Source and the Future of Routing Software
Almost every company relies on open source software in some way, which leads to the natural question—how will the heart of the network, routing and switching, be impacted by open source software? In this episode of the Hedge, Sue Hares, Donald Sharp, and Russ White discuss the current and future world of open source routing software. Donald is one of the main drivers of the FR Routing open source routing stack; Russ White is a maintainer on the project and is still deeply involved in commercial routing software, and Sue Hares was deeply involved in the origins of the GateD open source routing stack.
Service Provider Tech Doesn’t Apply?
Service provider problems are not your problems. You should not be trying to solve your problems the same way service providers do.
This seems intuitively true—after all, just about everything about a train or a large over-the-road truck (or lorry) is different from a passenger car. If the train is the service provider network and the car is the “enterprise” network, it seems to be obvious the two have very little in common.
Or is it?
What this gets right is that if an operator sells access to their network, or a single application, their network is likely to be built differently than the more general-purpose designs used in organizations that must support a wide range of applications and purposes. These differences are likely to show up in the choice of hardware, how the network is operated, and the kinds of services offered (or not).
The Hedge 7: Leslie Daigle and Internet Invariants
Some things always change, and some things never change. In this episode of the Hedge, Leslie Daigle joins Phill Simonds and Russ White to discuss her research into the things that do not change—and whether or not those things really have changed over the years since her original report for the Internet Society on Internet invariants.
Is it planning… or just plain engineering?
Over at the ECI blog, Jonathan Homa has a nice article about the importance of network planning–
Jonathan describes why this is so–traffic is constantly increasing, and the choice of tools we have to support the traffic loads of today and tomorrow can be classified in two ways: slim and none (as I remember a weather forecaster saying when I “wore a younger man’s shoes”). The problem, however, is not just tools. The network is increasingly seen as a commodity, “pure bandwidth that should be replaceable like memory,” made up of entirely interchangeable parts and pieces, primarily driven by the cost to move a bit across a given distance.
Autonomic, Automated, and Reality
Once the shipping department drops the box off with that new switch, router, or “firewall,” what happens next? You rack it, cable it up, turn it on, and start configuring, right? There are access to controls to configure—SSH, keys, disabling standard accounts, disabling telnet—interface addresses to configure, routing adjacencies to configure, local policies to configure, and… After configuring all of this, you can adjust routing in the network to route around the new device, and then either canary the device “in production” (if you run your network the way it should be run), or find some prearranged maintenance time to bring the new device online and test things out. After all of this, you can leave the new device up and running in the network, and move on to the next task.
Until it breaks.