--- title: On Routing Protocol Metrics « ipSpace.net blog | daily.dev description: A correction to a LinkedIn claim that BGP uniquely uses multiple metrics for path selection. All routing protocols use metrics — either scalar (RIP, OSPF,... canonical: https://daily.dev/posts/on-routing-protocol-metrics-ipspace-net-blog-7imrrxf2n twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: On Routing Protocol Metrics « ipSpace.net blog | daily.dev og:description: A correction to a LinkedIn claim that BGP uniquely uses multiple metrics for path selection. All routing protocols use metrics — either scalar (RIP, OSPF,... og:url: https://daily.dev/posts/on-routing-protocol-metrics-ipspace-net-blog-7imrrxf2n og:image: https://api.daily.dev/og/posts/7imRRxf2n.png og:image:alt: On Routing Protocol Metrics « 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 Routing Protocol Metrics « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 4 min read · 0 upvotes · 0 comments ## Summary A correction to a LinkedIn claim that BGP uniquely uses multiple metrics for path selection. All routing protocols use metrics — either scalar (RIP, OSPF, IS-IS) or vector (EIGRP, BGP). EIGRP is a clear counterexample: it uses a vector metric with components like delay, bandwidth, MTU, and reliability, then computes a composite scalar for path comparison. BGP uses a strict precedence order among its vector components (weight, local preference, AS path, MED, next-hop IGP cost). The post also touches on IGP Flexible Algorithm (RFC 9350), which extends OSPF and IS-IS with custom vector metric comparison, and explains why EIGRP's two-stage metric process exists — different components accumulate differently across hops. ## 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 difference between scalar and vector metrics in routing protocols? Scalar metrics are single values used by RIP, OSPF, and IS-IS to compare paths; vector metrics are sets of values used by EIGRP and BGP. EIGRP converts its vector metric (delay, bandwidth, MTU, reliability, hop count) into a composite scalar for path selection. BGP keeps its vector and applies a strict precedence order — local preference outweighs AS-path length, for example. _Network engineers sorting out path selection behavior find the nuances covered on daily.dev._ ### Why should I tweak EIGRP delay instead of bandwidth when influencing path selection? EIGRP delay is accumulated (added) across hops, while bandwidth is minimized — only the lowest bandwidth link in the path matters. Tweaking delay gives predictable, additive influence over the composite metric across the full path, whereas changing bandwidth only affects the result if that link is already the bottleneck. _Engineers tuning EIGRP traffic engineering keep up with protocol behavior discussions on daily.dev._ ### What is IGP Flexible Algorithm and which protocols support it? IGP Flexible Algorithm, defined in RFC 9350, extends OSPF and IS-IS with TLVs that let operators define custom vector metric comparison algorithms and use various vector metric components. It moves link-state protocols beyond simple additive scalar costs, enabling traffic engineering and constraint-based routing without requiring a separate overlay protocol. _Networking professionals evaluating modern IGP capabilities track RFC developments and protocol news on daily.dev._ ## Similar posts on daily.dev - [A framework for measuring Internet resilience](https://daily.dev/posts/a-framework-for-measuring-internet-resilience-ej9eg4ku0) · Cloudflare · 0 upvotes · 0 comments - [IP Is Better Than Ever with Integrated Performance Measurement](https://daily.dev/posts/ip-is-better-than-ever-with-integrated-performance-measurement-avswfceh7) · Cisco · 0 upvotes · 0 comments - [BGP ORIGIN attribute manipulation and its impact on the Internet](https://daily.dev/posts/bgp-origin-attribute-manipulation-and-its-impact-on-the-internet-fpdysqlcf) · Cloudflare · 2 upvotes · 0 comments --- Tags: [#networking](https://daily.dev/tags/networking), [#bgp](https://daily.dev/tags/bgp) [View this post on daily.dev](https://daily.dev/posts/on-routing-protocol-metrics-ipspace-net-blog-7imrrxf2n) ```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 Routing Protocol Metrics « ipSpace.net blog","url":"https://daily.dev/posts/on-routing-protocol-metrics-ipspace-net-blog-7imrrxf2n","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/on-routing-protocol-metrics-ipspace-net-blog-7imrrxf2n"},"datePublished":"2026-08-11T08:54:41.826Z","dateModified":"2026-08-11T09:03:52.798Z","description":"A correction to a LinkedIn claim that BGP uniquely uses multiple metrics for path selection. 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