Re: Understanding NAT, Firewalls, TCP/IP

Nigel Wade wrote:

> Most home NAT routers don't even have a firewall. Those which do are
> generally shipped with the firewall disabled.

Both of the home NATers that I've had have included firewalls. The first (a
cheap thing) had only simple firewalling, but it was there and was turned on by
default. IIRC it blocked "random" outgoing connections by default (but that
was some time ago and I could be wrong). My current NATing router features a
decidedly more elaborate firewall, and that certainly shipped in a default
configuration disallowing outbound connections on arbitrary ports.

Oh, and it doesn't and won't -- as a matter of manufacturer's security
policy -- support UPnP.

I /could/ allow outgoing connections on any ports I liked, but I see no good
reason to do so for any except a very small number of protocols. I
/definitely/ wouldn't open up a port in order to take part in a BitTorrent-like
distribution scheme.

-- chris


.

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