Security Basics mailing list archives
RE: Securing a Local Network
From: Meidinger Chris <chris.meidinger () badenit de>
Date: Mon, 19 Apr 2004 08:26:39 +0200
Hallo Andreas, there are definitely advantages to using a proper firewall, beyond simple defense in depth. The primary one, is that you will have to allow a lot of different ports on the local network. That means that the compromise of a single misconfigured host will result in the compromise of the entire network. What about, for example, a virus or trojan? A desktop firewall will not likely protect from call-home malware that opens a connection itself to an internet host waiting for a shell. For this and other reasons, conventional wisdom dictates that a central chokepoint be created, where you can make a strong divide between the internal and external network. If you use a dedicated firewall, there is absolutely no reason not to use desktop firewalls. Simple defense in depth is an advantage, but if you can correlate logs, desktop firewalls can also turn into a sort of IDS to alert you if an internal host is scanning or exploiting machines. If you want to talk at more length or in german, feel free to mail, Cheers, Chris
-----Original Message----- From: webmaster [mailto:webmaster () play-by-mail de] Sent: Thursday, April 15, 2004 11:21 AM To: roberts () tridecap com; security-basics () securityfocus com Subject: Re: Securing a Local Network Hi John, even if you have a virus protection at the gateway, you still need it on the clients. People use usb-sticks, notebooks and things like that. Another problem is the fact, that gateway protection cant protect you against password protected email attachments. So the best way is a combination of both. If you want to save money, give up fileserver-protection. I have got 2 other questions, regarding your issue, which might be interesting for you, too. If I do not host my own services, is there a advantage to protect my network through a packetfilter or even a statefull inspection firewall appliance? Or is it enough to use NAT in combination with personal firewalls on every desktop? If I use a firewall appliance, do I still need personal firewalls on the desktops? I guess I do. One benefit are internal attacks using tools like superscan. Am I right? Other benefits? Regards Andreas John Roberts wrote:I started working as a sys admin at a small company (about15 people)and they are starting to think it's time to upgrade their network. Right now it's just 20 computers, running a mix of xp and 2000 on a local network, sharing files, with almost no anti virus andthe onlyprotection from the outside world is the NAT that therouters perform.I've tried to get the to upgrade to a domain, add a file server for backup, get some office wide virus protection and maybeeven take ouremail in house, but they've balked at the price to setup a legit windows domain. The main goals are access control on the local network and virus / worm protection. I'm suggesting aWindows domaincontroller to enforce access control and then an centralized anti-virus product. Is this enough, and are there other (easier, cheaper, more effective ways) to make sure that only the people who need to can access the financial records, the computer people can access the all computers when they need to, and some userdecides to download a cute little program won't destroy the whole network with a virus.Is a linux domain controller a solution, consideringeverything elsein house is windows? Is an anti-virus solution at thegateway betterthan an anti-virus solution on each desktop? Basically,what's a goodway to set up a solid base of network security, which canthen be expanded on?John Roberts--------------------------------------------------------------------------- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes areguaranteed to be10 students or less to facilitate one-on-one interactionwith one ofour expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to betterassess the security of your organization.Visit us at:http://www.infosecinstitute.com/courses/ethical_hacking_training.html------------------------------------------------------------------------------------------------------------------------------------------ ------------- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes are guaranteed to be 10 students or less to facilitate one-on-one interaction with one of our expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to better assess the security of your organization. Visit us at: http://www.infosecinstitute.com/courses/ethical_hacking_training.html -------------------------------------------------------------- --------------
--------------------------------------------------------------------------- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes are guaranteed to be 10 students or less to facilitate one-on-one interaction with one of our expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to better assess the security of your organization. Visit us at: http://www.infosecinstitute.com/courses/ethical_hacking_training.html ----------------------------------------------------------------------------
Current thread:
- Securing a Local Network John Roberts (Apr 14)
- RE: Securing a Local Network John Lewis (Apr 14)
- Re: Securing a Local Network webmaster (Apr 15)
- <Possible follow-ups>
- RE: Securing a Local Network Henry, Christopher M. (Apr 14)
- RE: Securing a Local Network Halverson, Chris (Apr 14)
- RE: Securing a Local Network Eric Curbo (Apr 15)
- RE: Securing a Local Network Meidinger Chris (Apr 15)
- RE: Securing a Local Network Meidinger Chris (Apr 19)
- Re: Securing a Local Network Greg (Apr 20)
- RE: Securing a Local Network Meidinger Chris (Apr 19)
- RE: Securing a Local Network Steven Trewick (Apr 24)