--- title: On MPLS Paths, Tunnels and Interfaces « ipSpace.net blog description: A deep dive into the fundamental differences between MPLS paths and IP tunneling technologies like GRE, IPsec, and VXLAN. MPLS was originally designed as a... canonical: https://daily.dev/posts/on-mpls-paths-tunnels-and-interfaces-ipspace-net-blog-nitligm1g twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: On MPLS Paths, Tunnels and Interfaces « ipSpace.net blog | daily.dev og:description: A deep dive into the fundamental differences between MPLS paths and IP tunneling technologies like GRE, IPsec, and VXLAN. MPLS was originally designed as a... og:url: https://daily.dev/posts/on-mpls-paths-tunnels-and-interfaces-ipspace-net-blog-nitligm1g og:image: https://api.daily.dev/og/posts/NiTligM1G.png og:image:alt: On MPLS Paths, Tunnels and Interfaces « 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. # On MPLS Paths, Tunnels and Interfaces « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 4 min read · 0 upvotes · 0 comments ## Summary A deep dive into the fundamental differences between MPLS paths and IP tunneling technologies like GRE, IPsec, and VXLAN. MPLS was originally designed as a better packet forwarding mechanism within a single network, not as a tunneling technology. Tunnels connect discontiguous overlay network segments across an underlay, requiring routing protocols over tunnel interfaces. MPLS paths, by contrast, are created dynamically based on IP routing tables and don't expose interfaces in the same way. The post also covers the historical origins of Tag Switching (performance and ATM integration), MPLS TE tunnel unidirectionality, and why GRE tunnels work for multicast VPN scenarios where MPLS LSPs fall short. Comments add historical context about BGP-MPLS-VPNs being the real killer app, and a discussion of SRv6 as a hybrid approach. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the fundamental difference between an MPLS LSP and a GRE tunnel? MPLS paths are a packet forwarding mechanism within a single network, created dynamically from the IP routing table without exposing tunnel interfaces. GRE and similar tunnels connect discontiguous overlay network segments across an underlay, requiring routing protocols over explicit tunnel interfaces. MPLS was never designed to carry overlay reachability information the way tunnels do, which is why GRE works for multicast VPN scenarios where MPLS LSPs fail. _Engineers choosing between MPLS and overlay tunneling for VPN designs track these architectural distinctions on daily.dev._ ### Why was MPLS originally invented and what was its initial use case? MPLS originated from Cisco's Tag Switching technology, designed primarily to improve packet forwarding performance — specifically to leverage ATM switches inside IP networks at a time when ATM hardware was significantly faster and cheaper than IP routers. RFC 2105 from 1997 explicitly frames Tag Switching as blending routing flexibility with label-swapping simplicity to achieve improved forwarding performance and competitive price/performance. _Networking engineers revisiting MPLS history and architecture find the full context on daily.dev._ ## Similar posts on daily.dev - [MPLS/VPN with SR-MPLS Core « ipSpace.net blog](https://daily.dev/posts/mpls-vpn-with-sr-mpls-core-ipspace-net-blog-nw3uwiphe) · ipSpace.net Blog · 0 upvotes · 0 comments --- Tags: [#networking](https://daily.dev/tags/networking), [#vpn](https://daily.dev/tags/vpn) [View this post on daily.dev](https://daily.dev/posts/on-mpls-paths-tunnels-and-interfaces-ipspace-net-blog-nitligm1g) ```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":"On MPLS Paths, Tunnels and Interfaces « ipSpace.net blog","url":"https://daily.dev/posts/on-mpls-paths-tunnels-and-interfaces-ipspace-net-blog-nitligm1g","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/on-mpls-paths-tunnels-and-interfaces-ipspace-net-blog-nitligm1g"},"datePublished":"2026-08-11T08:55:55.741Z","dateModified":"2026-08-11T09:36:19.242Z","description":"A deep dive into the fundamental differences between MPLS paths and IP tunneling technologies like GRE, IPsec, and VXLAN. 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