A NAT router (sometimes referred to as a gateway) creates a
local area network (LAN) of private IP addresses and
interconnects that LAN to the wide area network (WAN) known
as the Internet. The "Network Address Translation" (NAT)
performed by the router allows multiple computers, smart
phones, tablets, and other devices connected to the LAN
behind the router to communicate with the external Internet.
One should download the Manual (PDF) for your Modem, Router,
and/or Modem-Router combination.
THE CHECKLIST PODCAST 89: ROUTER RUNDOWN (22+ min)
Routers -- Most everybody has one at home. But most of us
don't know anything about our routers. If the router gets
hacked the bad guys can get everything!
WARNING ABOUT ROUTERS
Most gateway routers used by home customers are profoundly
not secure. Some routers are so vulnerable to attack that
they should be thrown out, a security expert said at the
HOPE X hacker conference in New York.
"If a router is sold at [a well-known retail electronics
chain], you don't want to buy it," independent computer
consultant Michael Horowitz said in a presentation.
"If your router is given to you by your Internet Service
Provider (ISP), you don't want to use it either, because
they give away millions of them, and that makes them a prime
target both for spy agencies and bad guys."
ROUTER BUGS, FLAWS, HACKS, AND VULNERABILITIES
If you care about the security of your router, and you
should, it is best to avoid consumer grade routers. On the
whole, the software in these routers is buggy as heck.
SUGGESTED SECURE ROUTERS