{"id":1328,"date":"2020-11-28T17:09:00","date_gmt":"2020-11-28T17:09:00","guid":{"rendered":"http:\/\/bytereign.com\/?p=1328"},"modified":"2025-04-22T10:22:58","modified_gmt":"2025-04-22T09:22:58","slug":"ipv4-subnetting-a-quick-overview","status":"publish","type":"post","link":"https:\/\/bytereign.com\/?p=1328","title":{"rendered":"IPv4 Subnetting: A Quick Overview"},"content":{"rendered":"\t\t
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The practice of dividing a network into two or more networks is called subnetting. We steal bits from the hosts to create more subnets.<\/span><\/p>

Public IP range \u2013 Used with the public network ex. WAN; Recognized over the internet, assigned by IANA or service provider. globally unique, cost associated with public IP.<\/span><\/p>

\u00a0<\/p>

CLASS<\/span><\/p><\/td>

IP Address Range<\/span><\/p><\/td>

Network Mask<\/span><\/p><\/td>

Prefix<\/span><\/p><\/td>

Number of Networks<\/span><\/p><\/td>

Number of hosts<\/span><\/p><\/td><\/tr>

A<\/span><\/p><\/td>

1 to 126 \u2013 Used for huge networks, like those deployed by Internet Service Providers (ISPs).<\/span><\/p><\/td>

255.0.0.0<\/span><\/p><\/td>

\/8<\/span><\/p><\/td>

125<\/span><\/p><\/td>

16,777,241<\/span><\/p><\/td><\/tr>

B<\/span><\/p><\/td>

128 to 191 \u2013 Used for medium and large-sized networks in enterprises and organizations<\/span><\/p><\/td>

255.255.0.0<\/span><\/p><\/td>

\/16<\/span><\/p><\/td>

16,382<\/span><\/p><\/td>

65,534<\/span><\/p><\/td><\/tr>

C<\/span><\/p><\/td>

192 to 223 \u2013 Used for small-sized networks.<\/span><\/p><\/td>

255.255.255.0<\/span><\/p><\/td>

\/24<\/span><\/p><\/td>

2,097,150<\/span><\/p><\/td>

254<\/span><\/p><\/td><\/tr>

D<\/span><\/p><\/td>

224 to 239 \u2013 Used for multicasting applications<\/span><\/p><\/td>

Multicast Addresses<\/span><\/p><\/td><\/tr>

E<\/span><\/p><\/td>

240 to 254 \u2013 Reserved for experimental purposes only for R&D or Study.<\/span><\/p><\/td>

R&D, Restricted\/Experimental<\/span><\/p><\/td><\/tr><\/tbody><\/table>

\u00a0<\/p>

The above table is standard and good to remember but the actual range will look like below after excluding private IP range.<\/span><\/p>

\u00a0<\/p>

CLASS A<\/span><\/p><\/td>

1.0.0.0 – 9.255.255.255<\/span><\/p>

11.0.0.0 – 126.255.255.255<\/span><\/p><\/td><\/tr>

CLASS B<\/span><\/p><\/td>

128.0.0.0 – 172.15.255.255<\/span><\/p>

172.32.0.0 – 191.255.255.255<\/span><\/p><\/td><\/tr>

CLASS C<\/span><\/p><\/td>

192.0.0.0 – 192.167.255.255<\/span><\/p>

192.169.0.0 – 223.255.255.255<\/span><\/p><\/td><\/tr><\/tbody><\/table>

\u00a0<\/p>

127.0.0.0 is reserved for loopback (localhost).<\/span><\/p>

\u00a0<\/p>

Private IP range \u2013 Used with the private network ex. LAN; Not recognized over the internet, assigned by LAN Admin. unique only in LAN segment. free of charge.<\/span><\/p>

\u00a0<\/p>

CLASS A<\/span><\/p><\/td>

10.0.0.0 – 10.255.255.255 \u2013 Used for private network, local LAN.<\/span><\/p><\/td><\/tr>

CLASS B<\/span><\/p><\/td>

172.16.0.0 – 172.31.255.255 \u2013 Used for private network, local LAN.<\/span><\/p><\/td><\/tr>

CLASS C<\/span><\/p><\/td>

192.168.0.0 – 192.168.255.255 \u2013 Used for private network, local LAN.<\/span><\/p><\/td><\/tr><\/tbody><\/table>

\u00a0<\/p>

Types of Subnetting<\/span><\/p>

  • Fixed Length Subnetting – All the subnets are of same size, same subnet mask, equal number of hosts. It is also called as classful subnetting.<\/span><\/li>
  • Variable Length Subnetting – All the subnets are not of same size, do not have same subnet mask, no equal number of hosts. It is also called as classless subnetting<\/span><\/li><\/ul>

    \u00a0<\/p>

    Types of addresses<\/span><\/p>

    • Network address – Network address represents the network.<\/span><\/li><\/ul>
      • Broadcast address – Broadcast address represents all the hosts which belong to it.<\/span><\/li><\/ul>

        \u00a0<\/p>

        Subnetting Table (Class A) \u2013<\/span><\/p>

        \u00a0<\/p>

        NetBits<\/span><\/p><\/td>

        Network Mask<\/span><\/p><\/td>

        Subnets<\/span><\/p><\/td>

        Number of Hosts<\/span><\/p><\/td><\/tr>

        \/8<\/span><\/p><\/td>

        255.0.0.0<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        16,777,214<\/span><\/p><\/td><\/tr>

        \/9<\/span><\/p><\/td>

        255.128.0.0<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        8,388,606<\/span><\/p><\/td><\/tr>

        \/10<\/span><\/p><\/td>

        255.192.0.0<\/span><\/p><\/td>

        2<\/span><\/p><\/td>

        4,194,302<\/span><\/p><\/td><\/tr>

        \/11<\/span><\/p><\/td>

        255.224.0.0<\/span><\/p><\/td>

        6<\/span><\/p><\/td>

        2,097,150<\/span><\/p><\/td><\/tr>

        \/12<\/span><\/p><\/td>

        255.240.0.0<\/span><\/p><\/td>

        14<\/span><\/p><\/td>

        1,048,574<\/span><\/p><\/td><\/tr>

        \/13<\/span><\/p><\/td>

        255.248.0.0<\/span><\/p><\/td>

        30<\/span><\/p><\/td>

        524,286<\/span><\/p><\/td><\/tr>

        \/14<\/span><\/p><\/td>

        255.252.0.0<\/span><\/p><\/td>

        62<\/span><\/p><\/td>

        262,142<\/span><\/p><\/td><\/tr>

        \/15<\/span><\/p><\/td>

        255.254.0.0<\/span><\/p><\/td>

        126<\/span><\/p><\/td>

        131,070<\/span><\/p><\/td><\/tr>

        \/16<\/span><\/p><\/td>

        255.255.0.0<\/span><\/p><\/td>

        254<\/span><\/p><\/td>

        65,534<\/span><\/p><\/td><\/tr>

        \/17<\/span><\/p><\/td>

        255.255.128.0<\/span><\/p><\/td>

        510<\/span><\/p><\/td>

        32,766<\/span><\/p><\/td><\/tr>

        \/18<\/span><\/p><\/td>

        255.255.192.0<\/span><\/p><\/td>

        1,022<\/span><\/p><\/td>

        16,382<\/span><\/p><\/td><\/tr>

        \/19<\/span><\/p><\/td>

        255.255.224.0<\/span><\/p><\/td>

        2,046<\/span><\/p><\/td>

        8,190<\/span><\/p><\/td><\/tr>

        \/20<\/span><\/p><\/td>

        255.255.240.0<\/span><\/p><\/td>

        4,094<\/span><\/p><\/td>

        4,094<\/span><\/p><\/td><\/tr>

        \/21<\/span><\/p><\/td>

        255.255.248.0<\/span><\/p><\/td>

        8,190<\/span><\/p><\/td>

        2,046<\/span><\/p><\/td><\/tr>

        \/22<\/span><\/p><\/td>

        255.255.252.0<\/span><\/p><\/td>

        16,382<\/span><\/p><\/td>

        1,022<\/span><\/p><\/td><\/tr>

        \/23<\/span><\/p><\/td>

        255.255.254.0<\/span><\/p><\/td>

        32,766<\/span><\/p><\/td>

        510<\/span><\/p><\/td><\/tr>

        \/24<\/span><\/p><\/td>

        255.255.255.0<\/span><\/p><\/td>

        65,534<\/span><\/p><\/td>

        254<\/span><\/p><\/td><\/tr>

        \/25<\/span><\/p><\/td>

        255.255.255.128<\/span><\/p><\/td>

        131,070<\/span><\/p><\/td>

        126<\/span><\/p><\/td><\/tr>

        \/26<\/span><\/p><\/td>

        255.255.255.192<\/span><\/p><\/td>

        262,142<\/span><\/p><\/td>

        62<\/span><\/p><\/td><\/tr>

        \/27<\/span><\/p><\/td>

        255.255.255.224<\/span><\/p><\/td>

        524,286<\/span><\/p><\/td>

        30<\/span><\/p><\/td><\/tr>

        \/28<\/span><\/p><\/td>

        255.255.255.240<\/span><\/p><\/td>

        1,048,574<\/span><\/p><\/td>

        14<\/span><\/p><\/td><\/tr>

        \/29<\/span><\/p><\/td>

        255.255.255.248<\/span><\/p><\/td>

        2,097,150<\/span><\/p><\/td>

        6<\/span><\/p><\/td><\/tr>

        \/30<\/span><\/p><\/td>

        255.255.255.252<\/span><\/p><\/td>

        4,194,302<\/span><\/p><\/td>

        2<\/span><\/p><\/td><\/tr><\/tbody><\/table>

        \u00a0<\/p>

        Subnetting Table (Class B) \u2013<\/span><\/p>

        \u00a0<\/p>

        NetBits<\/span><\/p><\/td>

        Network Mask<\/span><\/p><\/td>

        Subnets<\/span><\/p><\/td>

        Number of Hosts<\/span><\/p><\/td><\/tr>

        \/16<\/span><\/p><\/td>

        255.255.0.0<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        65,534<\/span><\/p><\/td><\/tr>

        \/17<\/span><\/p><\/td>

        255.255.128.0<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        32,766<\/span><\/p><\/td><\/tr>

        \/18<\/span><\/p><\/td>

        255.255.192.0<\/span><\/p><\/td>

        2<\/span><\/p><\/td>

        16,382<\/span><\/p><\/td><\/tr>

        \/19<\/span><\/p><\/td>

        255.255.224.0<\/span><\/p><\/td>

        6<\/span><\/p><\/td>

        8,190<\/span><\/p><\/td><\/tr>

        \/20<\/span><\/p><\/td>

        255.255.240.0<\/span><\/p><\/td>

        14<\/span><\/p><\/td>

        4,094<\/span><\/p><\/td><\/tr>

        \/21<\/span><\/p><\/td>

        255.255.248.0<\/span><\/p><\/td>

        30<\/span><\/p><\/td>

        2,046<\/span><\/p><\/td><\/tr>

        \/22<\/span><\/p><\/td>

        255.255.252.0<\/span><\/p><\/td>

        62<\/span><\/p><\/td>

        1,022<\/span><\/p><\/td><\/tr>

        \/23<\/span><\/p><\/td>

        255.255.254.0<\/span><\/p><\/td>

        126<\/span><\/p><\/td>

        510<\/span><\/p><\/td><\/tr>

        \/24<\/span><\/p><\/td>

        255.255.255.0<\/span><\/p><\/td>

        254<\/span><\/p><\/td>

        254<\/span><\/p><\/td><\/tr>

        \/25<\/span><\/p><\/td>

        255.255.255.128<\/span><\/p><\/td>

        510<\/span><\/p><\/td>

        126<\/span><\/p><\/td><\/tr>

        \/26<\/span><\/p><\/td>

        255.255.255.192<\/span><\/p><\/td>

        1,022<\/span><\/p><\/td>

        62<\/span><\/p><\/td><\/tr>

        \/27<\/span><\/p><\/td>

        255.255.255.224<\/span><\/p><\/td>

        2,046<\/span><\/p><\/td>

        30<\/span><\/p><\/td><\/tr>

        \/28<\/span><\/p><\/td>

        255.255.255.240<\/span><\/p><\/td>

        4,094<\/span><\/p><\/td>

        14<\/span><\/p><\/td><\/tr>

        \/29<\/span><\/p><\/td>

        255.255.255.248<\/span><\/p><\/td>

        8,190<\/span><\/p><\/td>

        6<\/span><\/p><\/td><\/tr>

        \/30<\/span><\/p><\/td>

        255.255.255.252<\/span><\/p><\/td>

        16,382<\/span><\/p><\/td>

        2<\/span><\/p><\/td><\/tr><\/tbody><\/table>

        \u00a0<\/p>

        Subnetting Table (Class C) \u2013<\/span><\/p>

        \u00a0<\/p>

        NetBits<\/span><\/p><\/td>

        Network Mask<\/span><\/p><\/td>

        Subnets<\/span><\/p><\/td>

        Number of Hosts<\/span><\/p><\/td><\/tr>

        \/24<\/span><\/p><\/td>

        255.255.255.0<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        254<\/span><\/p><\/td><\/tr>

        \/25<\/span><\/p><\/td>

        255.255.255.128<\/span><\/p><\/td>

        0<\/span><\/p><\/td>

        126<\/span><\/p><\/td><\/tr>

        \/26<\/span><\/p><\/td>

        255.255.255.192<\/span><\/p><\/td>

        2<\/span><\/p><\/td>

        62<\/span><\/p><\/td><\/tr>

        \/27<\/span><\/p><\/td>

        255.255.255.224<\/span><\/p><\/td>

        6<\/span><\/p><\/td>

        30<\/span><\/p><\/td><\/tr>

        \/28<\/span><\/p><\/td>

        255.255.255.240<\/span><\/p><\/td>

        14<\/span><\/p><\/td>

        14<\/span><\/p><\/td><\/tr>

        \/29<\/span><\/p><\/td>

        255.255.255.248<\/span><\/p><\/td>

        30<\/span><\/p><\/td>

        6<\/span><\/p><\/td><\/tr>

        \/30<\/span><\/p><\/td>

        255.255.255.252<\/span><\/p><\/td>

        62<\/span><\/p><\/td>

        2<\/span><\/p><\/td><\/tr><\/tbody><\/table>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"

        The practice of dividing a network into two or more networks is called subnetting. We steal bits from the hosts to create<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_eb_attr":"","footnotes":""},"categories":[1,49],"tags":[],"class_list":["post-1328","post","type-post","status-publish","format-standard","hentry","category-blog","category-network-engineering"],"_links":{"self":[{"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/posts\/1328","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/bytereign.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1328"}],"version-history":[{"count":62,"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/posts\/1328\/revisions"}],"predecessor-version":[{"id":2014,"href":"https:\/\/bytereign.com\/index.php?rest_route=\/wp\/v2\/posts\/1328\/revisions\/2014"}],"wp:attachment":[{"href":"https:\/\/bytereign.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1328"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bytereign.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1328"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bytereign.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1328"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}