Do I need a router for protection?

[Bob]

My questions: Do I need a router for protection? Will it significantly
improve my protection? When does "The Law of Diminishing Returns" apply if
it would help just a little?

I have been reading about security. One site said a router makes my
computer "invisible" on the internet. And another said "In very basic
terms, a router will automatically reject unsolicited inbound communications
to your PC. It will not reject solicited, but malicious, communications.".

I am running PC Tools Firewall Plus Free as my firewall and Avast 5 for
malware protection. I have spent some time to learn how to work theses apps
and set to most secure. PC Tools Firewall Plus Free was rated #2 firewall
at matousec.com. I always use my computer in standard user account. If I
need to use admin account I unplug network cable if I do not need internet
for what I am doing. I looked up the specks of my cable modem and it is not
a router. I use a direct network wire from modem to my computer. (I do not
use anything "wireless" yet)

I tested my firewall at grc.com ShieldsUP! It passed every test except it
failed the ping test because it responded to a ping. I also tested at
grc.com LeakTest v1.2 and it failed in a strange way. When firewall alerted
me to LeakTest v1.2 with the usual pop up warning "Allow or Block", I
obviously blocked it as instructed by leaktest instructions, and immediately
LeakTest v1.2 claimed it connected to grc.com and stated I failed the test.
I suppose this is off subject because it is a matter to take up with PC
Tools and grc.com.

Background info: Desktop AMD 4400+ 64X2 4GB memory 320GB HD Acer
(AM3100-U3201A) purchased new February 2008 -- 32-bit MS Vista Home Premium
SP2 -- MS auto updates on. Comcast ISP 12mbps service W\ Motorola SURFboard
SB5101 Cable Modem direct to computer. No other switches or routers or
wireless or phone line or any other networking hardware hooked up to this
computer.

Thanks for the help
Bob

 

[DL]

IMO its a user who causes an infection, in nearly all cases, by dowloading /
installing something from a 'bad' scource.
A NAT enabled router will basically add a further 'firewall type'
enhancement to your connection.
Provided you have a decent firewall and AV, occassionally run a malaware
scanning tool you will be fine for any normal useage, and should'nt become
too paranoid.

 

[FromTheRafters]

http://www.windowsbbs.com/networking/25950-router-nat-firewall-discussion.html

My questions: Do I need a router for protection? Will it
significantly improve my protection? When does "The Law of
Diminishing Returns" apply if it would help just a little?

The little help an actual firewall device gives you is in the fact that
if your machine gets compromised by something that you invited in, it
becomes very difficult for that malware to compromise the device. The
firewall application (personal firewall / software firewall) runs on the
now compromised machine and can be circumvented in most cases if the
malware was written to do so.

I have been reading about security. One site said a router makes my
computer "invisible" on the internet. And another said "In very basic
terms, a router will automatically reject unsolicited inbound
communications to your PC. It will not reject solicited, but
malicious, communications.".

A device sitting between networks (even between the internet and a LAN
with only one member) is in a unique position to "filter" communication
packets. The most basic is SPI (Stateful Packet Inspection) where the
"state" of a packet is checked to determine whether it is an
initialization packet (sent to initialize a communication) or a
subsequent packet (sent as a response as in an ongoing communication).
Basically, if you run a server of some kind, you need to be able to
respond to incoming init packets - otherwise it is best to drop them
into the bit bucket (null device).

Personal firewalls attempt to implement this on the computer that they
hope to protect, although they no longer have that aforementioned
"unique position". If you download and execute malware with sufficient
privilege, you usurp the so-called firewall.

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