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jamaso 08-28-2002 06:57 AM

simple firewall questions
Hi! I'm assuming a certain number of things here, if they are wrong,please let me know .
I've been reading some stuff (mainly howto's) about security and i'd like to ask some simple questions :
1- Can one use iptables to build both filtering and router firewalls?
2- If filtering firewalls don't work easily with dynamic IP why and how is it used then ?
3- Why would one use a static IP adress instead of a dynamic IP, since the second is safer ?
4- How can i know which open ports there are in my computer ? ( from what i understand any given program that can comunicate with the "outside" is a open port , so basically i wanted to know where and who are these programs )
thank you for your time

MartBrooks 08-28-2002 07:09 AM

1. What's the difference?
2. They do work easily with dynamic IP.
3. No, it isn't.
4. man netstat


jamaso 08-28-2002 07:54 AM

thanks for the quick and "economic" reply .

jamaso 08-28-2002 08:17 AM

BTW what does this mean then? (regarding question 3)
"As soon as you have a stable address and a permanent connection, you lose the 'obscurity' advantage that a dynamic IP and sporadic connection provides. You must install a real 'front door'."

taken from "Introduction to Intrusion Protection and Network Security"

unSpawn 08-28-2002 11:58 AM

Obscurity, referring to the phrase "security by obscurity is no security". Try

jamaso 08-28-2002 12:57 PM

thanks a lot

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