{"id":560,"date":"2026-05-13T19:13:53","date_gmt":"2026-05-13T19:13:53","guid":{"rendered":"https:\/\/edk-tech.net\/?p=560"},"modified":"2026-05-13T19:55:21","modified_gmt":"2026-05-13T19:55:21","slug":"internet-protocol-ip","status":"publish","type":"post","link":"https:\/\/edk-tech.net\/?p=560","title":{"rendered":"IP Addressing &amp; Subnetting \u2014 Complete Guide"},"content":{"rendered":"\n<p>IP addressing is the foundation of all networking. Every device on a network must have a unique IP address, and subnetting determines how networks are divided, how many hosts they support, and how routing behaves.<\/p>\n\n\n\n<p>This guide covers <a href=\"https:\/\/edk-tech.net\/?glossary=internet-protocol-version-4\"\r\n                    class=\"yaw-glossary yaw-glossary-alt-link\"\r\n                    title=\"Internet Protocol version 4 (IPv4)\"\r\n                    data-bs-toggle=\"popover\"\r\n                    data-bs-html=\"true\"\r\n                    data-bs-trigger=\"hover focus\"\r\n                    data-bs-content=\"&lt;p&gt;IPv4 address classes Predefined ranges of IP addresses (Classes A, B, C, D, and E) designed to allocate addresses based on network size, with Class A for large networks, Class B for medium-sized networks, Class C for small networks, Class&hellip;&lt;\/p&gt;\n\">IPv4<\/a>, IPv6, subnet masks, CIDR notation, calculating network ranges, and converting between number systems \u2014 all using the formulas already shown in your Number Systems page .<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">IPv4 Addressing Basics<\/h2>\n\n\n\n<p>An IPv4 address is <strong>32 bits<\/strong>, producing:<\/p>\n\n\n\n<p><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><mrow><msup><mn>2<\/mn><mn>32<\/mn><\/msup><mo>=<\/mo><mn>4<\/mn><mo separator=\"true\">,<\/mo><mn>294<\/mn><mo separator=\"true\">,<\/mo><mn>967<\/mn><mo separator=\"true\">,<\/mo><mn>296<\/mn><mtext>&nbsp;total&nbsp;addresses<\/mtext><\/mrow><\/math><\/p>\n\n\n\n<p>IPv4 is written in <strong>dotted\u2011decimal<\/strong> format:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>192.168.1.10<\/code><\/pre>\n\n\n\n<p>Each octet is 8 bits.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Subnet Masks &amp; CIDR Notation<\/h3>\n\n\n\n<p>A subnet mask defines how many bits belong to:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Network portion<\/strong><\/li>\n\n\n\n<li><strong>Host portion<\/strong><\/li>\n<\/ul>\n\n\n\n<p>Example:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>255.255.255.0 = \/24<\/code><\/pre>\n\n\n\n<p>Meaning:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>24 network bits<\/li>\n\n\n\n<li>8 host bits<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Calculating Assignable Hosts<\/h3>\n\n\n\n<p><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><mrow><mtext>Assignable&nbsp;Hosts<\/mtext><mo>=<\/mo><msup><mn>2<\/mn><mi>h<\/mi><\/msup><mo>\u2212<\/mo><mn>2<\/mn><\/mrow><\/math><\/p>\n\n\n\n<p>Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><mrow><mi>h<\/mi><\/mrow><\/math> = number of host bits<\/li>\n\n\n\n<li>Subtract 2 for <strong>network<\/strong> and <strong>broadcast<\/strong> addresses<\/li>\n<\/ul>\n\n\n\n<p>Example: <code>\/24<\/code><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Host bits = 8<\/li>\n\n\n\n<li>Assignable = <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><mrow><msup><mn>2<\/mn><mn>8<\/mn><\/msup><mo>\u2212<\/mo><mn>2<\/mn><mo>=<\/mo><mn>254<\/mn><\/mrow><\/math><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Calculating Number of Subnets<\/h3>\n\n\n\n<p>Formula:<\/p>\n\n\n\n<p><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><mrow><mtext>Subnets<\/mtext><mo>=<\/mo><msup><mn>2<\/mn><mi>s<\/mi><\/msup><\/mrow><\/math><\/p>\n\n\n\n<p>Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><mrow><mi>s<\/mi><\/mrow><\/math> = number of <strong>borrowed bits<\/strong> (bits added to the default mask)<\/li>\n<\/ul>\n\n\n\n<p>Example: Borrow 3 bits \u2192 <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><mrow><msup><mn>2<\/mn><mn>3<\/mn><\/msup><mo>=<\/mo><mn>8<\/mn><\/mrow><\/math> subnets.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Interesting Octet &amp; Block Size<\/h3>\n\n\n\n<p>Formula:<\/p>\n\n\n\n<p><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><mrow><mtext>Block&nbsp;Size<\/mtext><mo>=<\/mo><mn>256<\/mn><mo>\u2212<\/mo><mtext>Interesting&nbsp;Octet<\/mtext><\/mrow><\/math><\/p>\n\n\n\n<p>The <strong>interesting octet<\/strong> is the octet where the subnet mask stops being 255.<\/p>\n\n\n\n<p>Example:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Mask: 255.255.255.192\nInteresting Octet = 192\nBlock Size = 256 - 192 = 64<\/code><\/pre>\n\n\n\n<p>Subnets:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>0\u201363\n64\u2013127\n128\u2013191\n192\u2013255<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">Calculating Network &amp; Broadcast Addresses<\/h3>\n\n\n\n<p>Given an IP and mask:<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>Step 1 \u2014 Find block size<\/strong><\/h4>\n\n\n\n<p>Use the formula above.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>Step 2 \u2014 Determine which block the IP falls into<\/strong><\/h4>\n\n\n\n<p>Example:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>IP: 192.168.1.130\nMask: \/26 (block size 64)<\/code><\/pre>\n\n\n\n<p>Blocks:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>0\u201363<\/li>\n\n\n\n<li>64\u2013127<\/li>\n\n\n\n<li>128\u2013191 \u2190 IP falls here<\/li>\n\n\n\n<li>192\u2013255<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>Step 3 \u2014 Network &amp; Broadcast<\/strong><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>Network:   192.168.1.128\nBroadcast: 192.168.1.191<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>Step 4 \u2014 Usable Range<\/strong><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>192.168.1.129 \u2013 192.168.1.190<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">Binary, Hex, and Octal Conversions<\/h2>\n\n\n\n<p>Your Number Systems page already includes the conversion examples:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Decimal \u2192 Hexadecimal<\/h3>\n\n\n\n<p>Example from your draft: 2748 \u2192 ABC (A=10, B=11, C=12)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Decimal \u2192 Binary<\/h3>\n\n\n\n<p>Repeated division by 2 (your draft shows the full breakdown)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Binary \u2192 Hex<\/h3>\n\n\n\n<p>Group bits into 4s.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Binary \u2192 Octal<\/h3>\n\n\n\n<p>Group bits into 3s.<\/p>\n\n\n\n<p>These conversions are essential for understanding subnetting at the bit level.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">IPv6 Addressing Basics<\/h2>\n\n\n\n<p>Your draft includes the total IPv6 address space:<\/p>\n\n\n\n<p><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><mrow><msup><mn>2<\/mn><mn>128<\/mn><\/msup><mo>=<\/mo><mn>3.4<\/mn><mo>\u00d7<\/mo><msup><mn>10<\/mn><mn>38<\/mn><\/msup><\/mrow><\/math><\/p>\n\n\n\n<p>IPv6 uses:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>128\u2011bit addresses<\/li>\n\n\n\n<li>Hexadecimal notation<\/li>\n\n\n\n<li>No broadcast addresses<\/li>\n\n\n\n<li>Vastly simplified subnetting<\/li>\n<\/ul>\n\n\n\n<p>Example:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>2001:db8:abcd:0012::\/64<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">CIDR Summary Table<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>CIDR<\/th><th>Hosts<\/th><th>Block Size<\/th><th>Notes<\/th><\/tr><\/thead><tbody><tr><td>\/24<\/td><td>254<\/td><td>1<\/td><td>Common LAN<\/td><\/tr><tr><td>\/25<\/td><td>126<\/td><td>128<\/td><td>Split \/24 in half<\/td><\/tr><tr><td>\/26<\/td><td>62<\/td><td>64<\/td><td>Cameras, IoT<\/td><\/tr><tr><td>\/27<\/td><td>30<\/td><td>32<\/td><td>Small networks<\/td><\/tr><tr><td>\/30<\/td><td>2<\/td><td>4<\/td><td>Point\u2011to\u2011point links<\/td><\/tr><\/tbody><\/table><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>IP addressing is the foundation of all networking. Every device on a network must have a unique IP address, and subnetting determines how networks are divided, how many hosts they support, and how routing behaves. This guide covers IPv4, IPv6, subnet masks, CIDR notation, calculating network ranges, and converting between number systems \u2014 all using [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":737,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"pagelayer_contact_templates":[],"_pagelayer_content":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[33,32],"tags":[],"class_list":{"0":"post-560","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-tech-math","8":"category-networking"},"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/peQefU-92","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/posts\/560","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/edk-tech.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=560"}],"version-history":[{"count":5,"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/posts\/560\/revisions"}],"predecessor-version":[{"id":1332,"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/wp\/v2\/posts\/560\/revisions\/1332"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/edk-tech.net\/index.php?rest_route=\/"}],"wp:attachment":[{"href":"https:\/\/edk-tech.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=560"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/edk-tech.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=560"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/edk-tech.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=560"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}