WyzGuys Computer Tutors

 Computer Instruction. Web Design Instruction,  and Web Hosting 

 

Implementing NAT

 

Site Navigation

Security Home
Registration
Security Resources
The Security Problem
Security Issues
The Control Panel
Computer Security
Network Security
System Restore
Repair Your System
911 Online
E-Mail Security
Spam
Phishing
Phishing Examples
Phishing Web Sites
419 Fraud
Parental Controls
Appendix
Conclusions
Course Evaluation

More Info

Glossary
Internet
E-Mail Attachments
Passwords
Firewalls
NAT
Ports
Broadband
WiFi Networks

Strengthen Security by Implementing Network Address Translation

Special thanks to Tech Republic for portions of this page

Network Address Translation (NAT) was originally developed to solve a problem with IP addressing.  As the number of computers on the Internet increased, there was a danger that there would not be enough IP addresses to provide every device a unique address.  NAT solved that problem by letting a device at the edge of a network, like a router, use a single public IP address to router traffic to computers on its network using non-routable private IP addresses.

As it turns out, NAT also increases security buy masking the actual address of a computer from view from the Internet side of the router.  Most of the available retail solutions from Linksys and  D-Link will use Dynamic NAT.  The type of NAT really doesn't matter for most business and all residential applications.  If you can enable NAT on a router or gateway device, do so.

NAT vs. proxy servers

People sometimes confuse NAT with the term proxy server. However, there's a big difference. NAT is transparent to both the source and destination computers. A proxy server is not transparent; you must configure a source computer to communicate with a proxy server.

In addition, the destination computer sends network requests to the proxy server, which forwards the communication back to the requesting computer. Proxy servers usually work at Layer 4 (Transport) or higher of the OSI Reference Model; NAT is a Layer 3 (Network) protocol.

Final thoughts

Don't worry that implementing NAT will cause a performance decrease on your network.

When implementing NAT, most simple routers utilize the Dynamic NAT approach. It creates a Layer-3 firewall between the internal network and the Internet.

This way, computers on the Internet can't connect to the internal client unless the internal client initiates the communication. Keeping hostile networks from connecting to your internal clients is a good beginning to securing your network.

   Close Window  

 

Curriculum developed by WyzGuys Computer Tutors

All Rights Reserved - updated 12/07/2006

Hosted by WyzHost.com

contact support@wyzhost.com