screened subnet
Home > Security Definitions - Screened subnet
SearchSecurity.com Definitions (Powered by WhatIs.com)
EMAIL THIS
LOOK UP TECH TERMS Powered by: WhatIs.com
Search listings for thousands of IT terms:
Browse tech terms alphabetically:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #

screened subnet



Digg This!    StumbleUpon Toolbar StumbleUpon    Bookmark with Delicious Del.icio.us   

DEFINITION - A screened subnet (also known as a "triple-homed firewall") is a network architecture that uses a single firewall with three network interfaces.

  • Interface 1 is the public interface and connects to the Internet.
  • Interface 2 connects to a DMZ (demilitarized zone) to which hosted public services are attached.
  • Interface 3 connects to an intranet for access to and from internal networks.
Even if the firewall itself is compromised, access to the intranet should not be available, as long as the firewall has been properly configured.

The purpose of the screened subnet architecture is to isolate the DMZ and its publicly-accessible resources from the intranet, thereby focusing external attention and any possible attack on that subnet. The architecture also separates the intranet and DMZ networks, making it more difficult to attack the intranet itself. When a properly configured firewall is combined with the use of private IP addresses on one or both of these subnets, attack becomes that much more difficult.

LAST UPDATED: 05 Feb 2008

Read more about screened subnet:
- For more information on screened subnets see Mike Chapple’s ‘Choosing the right firewall topology: Bastion host, screened subnet or dual firewalls’ at SearchSecurity.com.
- SearchSecurity.com's network firewalls topic offers relevant news, help and research.


Do you have something to add to this definition? Let us know.
Send your comments to techterms@whatis.com


BROWSE BY TAG
Network Security: Tools, Products, Software,   Network Firewalls, Routers and Switches,   Enterprise Network Security,   VIEW ALL TAGS

Digg This!    StumbleUpon Toolbar StumbleUpon    Bookmark with Delicious Del.icio.us   


RELATED CONTENT
Firewall rule management best practices
Michael Cobb offers best practices that can allow you to make changes to your company's firewall rule set without losing any sleep.
Should enterprises be running multiple firewalls?
While there may be scenarios where a single firewall is an appropriate architecture for an organization, it's equally true that many environments may...
What are the disadvantages of proxy-based firewalls?
Network security expert Mike Chapple explains why he strongly recommends the use of proxy-based firewalls.

RELATED GLOSSARY TERMS
Terms from Whatis.com − the technology online dictionary
bastion host  (SearchSecurity.com)
firewall  (SearchSecurity.com)
A firewall is a set of related programs, located at a network gateway server, that protects the resources of a private network from users from other...




Get More screened subnet Answers
Find Targeted screened subnet Answers for Channel Professionals
TechTarget Security Media
Information Security View this month\\'s issue and subscribe today.
Information Security Decisions Apply online for free conference admission.
SearchSecurity.com
HomeNewsMagazineMultimediaWhite PapersLearningAdviceTopicsEventsAbout Us

About Us  |  Contact Us  |  For Advertisers  |  For Business Partners  |  Site Index  |  RSS
TechTarget provides technology professionals with the information they need to perform their jobs - from developing strategy, to making cost-effective purchase decisions and managing their organizations' technology projects - with its network of technology-specific websites, events and online magazines.

TechTarget Corporate Web Site  |  Media Kits  |  Site Map




All Rights Reserved, Copyright 2003 - 2009, TechTarget | Read our Privacy Policy
  TechTarget - The IT Media ROI Experts