{"id":3840,"date":"2026-09-11T16:59:43","date_gmt":"2026-09-11T11:29:43","guid":{"rendered":"https:\/\/cybx.in\/blog\/?p=3840"},"modified":"2026-09-11T16:59:44","modified_gmt":"2026-09-11T11:29:44","slug":"do-network-switches-refer-to-ip-addresses","status":"publish","type":"post","link":"https:\/\/cybx.in\/blog\/do-network-switches-refer-to-ip-addresses\/","title":{"rendered":"Do Network Switches Refer to IP Addresses?"},"content":{"rendered":"\n<meta name=\"description\" content=\"A network switch does deal with IP addresses, but it doesn't normally use them to decide where an Ethernet frame should go. That's the bit that trips people \">\n<meta property=\"og:title\" content=\"Do Network Switches Refer to IP Addresses?\">\n<meta property=\"og:description\" content=\"A network switch does deal with IP addresses, but it doesn't normally use them to decide where an Ethernet frame should go. That's the bit that trips people \">\n<meta name=\"twitter:card\" content=\"summary_large_image\">\n<meta name=\"twitter:title\" content=\"Do Network Switches Refer to IP Addresses?\">\n<meta name=\"twitter:description\" content=\"A network switch does deal with IP addresses, but it doesn't normally use them to decide where an Ethernet frame should go. That's the bit that trips people \">\n\n\n<p>A network switch deals with IP addresses, technically. But it doesn&#8217;t actually use them to decide where an Ethernet frame goes. This is the bit that trips almost everyone up at some point. What a switch really looks at is the MAC address.<\/p>\n<h2>What a Network Switch Actually Looks At<\/h2>\n<p>Picture an office, a handful of computers plugged into the same switch. One sends a file over to another. Now the switch has a job: which port leads to the machine that&#8217;s supposed to receive it? So it checks the MAC address written into the Ethernet frame and fires it out the correct port. Done.<\/p>\n<p>How does it know which port goes where in the first place? It just watches. If one MAC address keeps turning up on port 6, the switch notes it down in a table and remembers. No setup, no configuration screen, nothing. It just picks it up by paying attention.<\/p>\n<h2>Where Does the IP Address Come In?<\/h2>\n<p>IP still matters, just not here, not at this layer. Your computer picks an IP address to identify whatever it&#8217;s trying to reach on the network. But before any of that data actually leaves over Ethernet, something called ARP has to step in, at least on IPv4, and go find the MAC address tied to that IP.<\/p>\n<p>So here&#8217;s roughly what happens. Your machine starts out knowing the destination IP, the logical address. ARP goes and tracks down the matching MAC address, assuming the target&#8217;s on the local network, and all of this happens before the switch is even involved. Once the switch sees that MAC address show up, it checks its table, and if the port&#8217;s known, off it goes.<\/p>\n<p>Is it technically wrong to say a switch uses IP addresses? Not entirely, not in every case. But for a regular Layer 2 switch, it&#8217;s misleading. MAC is what&#8217;s actually calling the shots.<\/p>\n<h2>What About Layer 3 Switches?<\/h2>\n<p>Here things shift a bit. A Layer 3 switch can route, meaning it actually does base decisions on IP addresses. It&#8217;s kind of a hybrid, switching and routing rolled into one box.<\/p>\n<p>Say a Layer 3 switch has a few different IP networks hanging off it. Traffic needs to get from one to the other? The switch looks at the destination IP this time and figures out where the packet should head next.<\/p>\n<h2>So, Does a Switch Refer to IP Addresses?<\/h2>\n<p>Short answer, not really, not a standard Layer 2 one anyway. MAC addresses drive the forwarding decision. IP is still in the picture somewhere, it&#8217;s just not what the switch itself is reading off to move frames around.<\/p>\n<p>Layer 3 switches break that rule though. They&#8217;ll look straight at IP info and route between networks when needed.<\/p>\n<p>Easiest way to keep the two straight? IP tells you where something is, logically speaking. MAC tells you which physical interface handles local delivery. A switch, most of the time, only cares about the second one.<\/p>","protected":false},"excerpt":{"rendered":"<p>A network switch deals with IP addresses, technically. But it doesn&#8217;t actually use them to decide where an Ethernet frame&#8230;<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[31],"tags":[],"class_list":["post-3840","post","type-post","status-publish","format-standard","hentry","category-learn"],"_links":{"self":[{"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/posts\/3840","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/comments?post=3840"}],"version-history":[{"count":1,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/posts\/3840\/revisions"}],"predecessor-version":[{"id":3857,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/posts\/3840\/revisions\/3857"}],"wp:attachment":[{"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/media?parent=3840"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/categories?post=3840"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cybx.in\/blog\/wp-json\/wp\/v2\/tags?post=3840"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}