CompTIA A+ Certification All-in-One Exam Guide

Figure 21-19 Common SOHO router with Wi-Fi
EXAM TIP Many computers can share a smaller pool of routable IP
addresses with dynamic NAT (DNAT). A NAT might have 10 routable IP
addresses, for example, to serve 40 computers on the LAN. LAN traffic uses
the internal, private IP addresses. When a computer requests information
beyond the network, the NAT doles out a routable IP address from its pool
for that communication. Dynamic NAT is also called Pooled NAT.
This works well enough—unless you’re the unlucky 11th person to try to
access the Internet from behind the company NAT—but has the obvious
limitation of still needing many true, expensive, routable IP addresses.
Basic Router Configuration
SOHO routers require very little in the way of configuration and in many
cases will work perfectly (if unsafely) right out of the box. In some cases,
though, you may have to deal with a more complex network that requires
changing the router’s settings. The vast majority of these routers have built-in
configuration Web pages that you access by typing the router’s IP address
into a browser. The address varies by manufacturer, so check the router’s
documentation. If you typed in the correct address, you should then receive a
prompt for a user name and password, as in Figure 21-20. As with the IP
address, the default user name and password vary depending on the
model/manufacturer. Once you enter the correct credentials, you will be
greeted by the router’s configuration pages (see Figure 21-21). From these
pages, you can change any of the router’s settings.