D-Link DSL300T: built-in firewall?

I recently got my father-in-law up & running on ADSL using a D-Link
DSL300T modem. (Thanks to those in this group who helped me out with a
tricky problem over his very long username). Now there's another issue
that's intriguing me. It's not a problem, just an observation....

Ever since he got the ADSL line going, his Norton firewall has
reported *zero* attacks/probes, which is somewhat surprising. He used
to get plenty on dial-up. Of course I got him to check that the
firewall is actually running, and he assures me it is. So then I
figured that the DSL300T must be providing a NAT service, but an
IPCONFIG shows this not to be the case (his PC has an externally
routable IP address). So now I'm surmising that maybe the DSL300T has
some kind of built-in firewall that stops unsolicited incoming
packets. Does anyone here know for sure? (My father-in-law is at the
other end of the country, and there's no manual available for
download, so I'm working in the dark here).
--
Clive Backham

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Clive Backham wrote:
> I recently got my father-in-law up & running on ADSL using a D-Link
> DSL300T modem. (Thanks to those in this group who helped me out with a
> tricky problem over his very long username). Now there's another issue
> that's intriguing me. It's not a problem, just an observation....
>
> Ever since he got the ADSL line going, his Norton firewall has
> reported *zero* attacks/probes, which is somewhat surprising. He used
> to get plenty on dial-up. Of course I got him to check that the
> firewall is actually running, and he assures me it is. So then I
> figured that the DSL300T must be providing a NAT service, but an
> IPCONFIG shows this not to be the case (his PC has an externally
> routable IP address). So now I'm surmising that maybe the DSL300T has
> some kind of built-in firewall that stops unsolicited incoming
> packets. Does anyone here know for sure? (My father-in-law is at the
> other end of the country, and there's no manual available for
> download, so I'm working in the dark here).

I have a 300t and I'm fairly sure it has one or the other. I've noticed
a log saying starting firewall, starting nat and the user manual
contains a picture showing tick boxes for nat and a firewall but these
are not in any firmware screen I can find. I've read that turning off
dhcp turns off nat or whatever. I use mine in bridge mode so none of
this applies.

You may be able to find out more by using the modem's telnet interface
and poking around. I think the username is root and the password is admin.



Fish