---
address: common.internet.ipv4
description: IPv4 in private ranges (10/8, 172.16/12, 192.168/16); octets 0-255
generator: tdc
---
<!-- Octets are numbers, not alternations. `(?:25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])`
     covers 0-255, but an alternation picks each of its four sides equally, so a
     quarter of every octet landed in 250-255 — six values with the weight of a
     hundred. The block itself stays an even three-way choice, as it was. -->
<sequence name="block"><gen type="text" value="10,172,192"/></sequence>
<sequence name="second"><gen type="number" value="0..255"/></sequence>
<sequence name="secondPrivate"><gen type="number" value="16..31"/></sequence>
<sequence name="third"><gen type="number" value="0..255"/></sequence>
<sequence name="fourth"><gen type="number" value="0..255"/></sequence>
<sequence name="ip"><compute>
  <result><choose>
    <when>
      <test><equals><to_number><field name="block"/></to_number><int v="10"/></equals></test>
      <then><concat>
        <str v="10."/><field name="second"/><str v="."/>
        <field name="third"/><str v="."/><field name="fourth"/>
      </concat></then>
    </when>
    <when>
      <test><equals><to_number><field name="block"/></to_number><int v="172"/></equals></test>
      <then><concat>
        <str v="172."/><field name="secondPrivate"/><str v="."/>
        <field name="third"/><str v="."/><field name="fourth"/>
      </concat></then>
    </when>
    <otherwise><concat>
      <str v="192.168."/><field name="third"/><str v="."/><field name="fourth"/>
    </concat></otherwise>
  </choose></result>
</compute></sequence>
<data>${{ip}}</data>