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<td bgcolor="#336666"><font face="Arial" size="2" color="#FFFFFF"><b>1.1</b></font></td>
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<td bgcolor="#336666" width="100%"><b>
<font face="Arial" size="2" color="#FFFFFF">Scaling Networks with NAT and
PAT</font></b></td>
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<td bgcolor="#669999" height="25"><b><font face="Arial" size="2" color="#FFFFFF">1.1.1</font></b></td>
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<b><font face="Arial" size="2" color="#FFFFFF">Private addressing</font></b> </td>
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<font face="Arial" size="2">RFC 1918 sets aside three blocks of
private IP addresses. They are one Class A address, 16 Class B addresses, and
256 Class C addresses. </font>
<font face="Arial" size="2" COLOR="#000000">
<img border="0" src="../../images/1.gif" align="absmiddle" width="12" height="12"></font><font face="Arial" size="2">
These addresses are for private, internal network use only. Packets
containing these addresses are not routed over the Internet</font><font face="Arial" size="2">.</font><font face="Arial" size="2" COLOR="#000000"> </font>
<p>
<font face="Arial" size="2" COLOR="#000000">Public Internet addresses must be
registered by a company with an Internet authority, for example, ARIN
or RIPE. These public Internet addresses can also be leased from an
ISP. Private IP addresses are reserved and can be used by anyone. That
means two networks, or two million networks, can each use the same
private address. A router should never route RFC 1918 addresses, because ISPs
typically configure the border routers to prevent privately addressed
traffic from being forwarded.</font></p>
<p>
<font FACE="Arial" SIZE="2" COLOR="#000000">
<font face="Arial" size="2">NAT provides great benefits to individual
companies and the Internet. Before NAT, a host with a private address
could not access the Internet. Using NAT, individual companies can
address some or all of their hosts with private addresses and use NAT
to provide access the Internet.</font></p>
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<p><font color="#808080">
<img border="0" src="../../images/links_icon.gif" width="25" height="25">
<b>Web Links</b></font></p>
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<p>Internet-Legal versus Private Addressing<p>
<a target="_blank" href="http://www.unoverica.com/documentation/ucm/mt211ai6.html">
http://www.unoverica.com/documentation/
ucm/mt211ai6.html</a></font></p>
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