Category: Windows
by Dennis Faas, infopackets editor
http://www.infopackets.com
Last week's question was about using a hardware and software firewall in
tandem, and whether or not a [Laptop] PC would be protected through a
firewall if it was daisy-chained to another [Desktop] PC which used a
software firewall.
Yes -- this is a very technical question, but certainly
very worth-while to know the answer to.
Here is what the connection might
look like if it was daisy chained:
Internet
connection -> Router, 1 port [hardware firewall] -> Desktop PC [software
firewall] -> Laptop [no firewall: is it protected from the Desktop PC's
software firewall?]
This type of daisy-chained connection varies
from a more common setup, where all PCs are connected to a Router and
operate their own software firewalls:
Internet connection ->
Router, 2+ ports
[hardware firewall] -> Desktop PC [+software firewall] AND Laptop PC
[+software firewall]
I didn't know the answer to this, so I asked
Gazette Readers to send me their thoughts. The consensus from readers
is that all PCs must use a software firewall.
Bill V. sums it up very
nicely:
" Firewall software only protects the OS it is installed in. An
ethernet card draws from the external server [TCP/IP] independently,
whether on not through a hub or router. "
Matthew T. had some very good points:
" I would suggest that in either of the configurations described in the
newsletter, a software firewall on both his PC and his Laptop should be
used. There are a number of reasons as to why I have come to this
conclusion:
- If he receives a virus onto his laptop or PC which propagates
through network shares (or other LAN measures), a software firewall
should provide some protection against it.
ZoneAlarm is a very good free personal firewall that asks you if you
would like to allow or deny ANY traffic that flows in and out of your
computer.
- Like you mentioned in your newsletter it would add an extra layer of
protection against a badly configured router. Again, in either of these
configurations described above a software firewall would be a good idea.
If a hacker manages to penetrate your router, he or she then has to get
past you software firewall before they can access your PC or Laptop.
- Most personal software firewalls are free! You really have no
excuses not to use one! "
Those were some good points made.
Trojans and Viruses can propagate on any PC regardless of Internet
connection. If a software firewall like
ZoneAlarm
isn't telling you what programs are attempting to access the network,
then there is no way of truly knowing if you are protected.
