--- title: SDN Controller Taxonomy « ipSpace.net blog | daily.dev description: A taxonomy of SDN controllers is proposed, cutting through marketing hype that labels almost any network management tool as an 'SDN controller.' Three main... canonical: https://daily.dev/posts/sdn-controller-taxonomy-ipspace-net-blog-hksdy6w28 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: SDN Controller Taxonomy « ipSpace.net blog | daily.dev og:description: A taxonomy of SDN controllers is proposed, cutting through marketing hype that labels almost any network management tool as an 'SDN controller.' Three main... og:url: https://daily.dev/posts/sdn-controller-taxonomy-ipspace-net-blog-hksdy6w28 og:image: https://api.daily.dev/og/posts/hKsDY6W28.png og:image:alt: SDN Controller Taxonomy « ipSpace.net blog og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # SDN Controller Taxonomy « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 3 min read · 0 upvotes · 0 comments ## Summary A taxonomy of SDN controllers is proposed, cutting through marketing hype that labels almost any network management tool as an 'SDN controller.' Three main categories are identified: centralized control plane solutions (largely failed due to physics/scaling), controllers that interact with the control plane (SD-WAN controllers, network virtualization controllers using EVPN), and orchestration systems that provision services by configuring network elements (e.g., Cisco ACI, SD-Access, Ubiquity UniFi). The post notes that some vendors simply rebrand traditional network management systems as SDN controllers. Comments extend the discussion to PCE controllers, OpenFlow's scaling limitations, and the absence of crafted-packet injection capabilities in standard IP networking. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What are the main categories of SDN controllers and how do they differ? SDN controllers fall into three categories: centralized control plane solutions (largely failed due to scaling issues), controllers that interact with the control plane (e.g., SD-WAN controllers acting as BGP route reflectors, network virtualization controllers using EVPN), and orchestration systems that provision services by configuring network elements in the background (e.g., Cisco ACI, Cisco SD-Access, Ubiquity UniFi SDN Controller). _Network engineers evaluating SDN products track vendor positioning and architecture debates on daily.dev._ ### Why did centralized control plane SDN fail? Centralized control plane SDN failed primarily due to the laws of physics — latency, reliability, and scalability constraints make it impractical to route all forwarding decisions through a central controller. Gartner declared SDN 'obsolete before plateau' in their 2021 Networking Hype Cycle, and most practitioners involved in the SDN movement eventually reached the same conclusion after the initial hype subsided. _Engineers making architecture decisions around network control planes find the ongoing debate covered on daily.dev._ ## Similar posts on daily.dev - [How the U.S. National Science Foundation Enabled Software-Defined Networking – Communications of the ACM](https://daily.dev/posts/how-the-u-s-national-science-foundation-enabled-software-defined-networking-communications-of-the-b0vpyyqzu) · Hacker News · 0 upvotes · 0 comments - [Unifying the data center with Cisco Nexus One: The network that works for you](https://daily.dev/posts/unifying-the-data-center-with-cisco-nexus-one-the-network-that-works-for-you-qx1wkt7zz) · Cisco · 0 upvotes · 0 comments - [Stop putting off VLANs in your homelab — Proxmox SDN makes them almost too easy](https://daily.dev/posts/stop-putting-off-vlans-in-your-homelab-proxmox-sdn-makes-them-almost-too-easy-p4xrm9vtr) · XDA Developers · 0 upvotes · 0 comments - [One open NOS, any workload: SONiC on Cisco](https://daily.dev/posts/one-open-nos-any-workload-sonic-on-cisco-ho9rhwjyb) · Cisco · 0 upvotes · 0 comments --- Tags: [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/sdn-controller-taxonomy-ipspace-net-blog-hksdy6w28) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"SDN Controller Taxonomy « ipSpace.net blog","url":"https://daily.dev/posts/sdn-controller-taxonomy-ipspace-net-blog-hksdy6w28","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/sdn-controller-taxonomy-ipspace-net-blog-hksdy6w28"},"datePublished":"2026-08-11T08:52:05.594Z","dateModified":"2026-08-11T09:00:29.270Z","description":"A taxonomy of SDN controllers is proposed, cutting through marketing hype that labels almost any network management tool as an 'SDN controller.' 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