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NAT for Newbies and Not So Newbies

Barry Stiefel

Barry Stiefel explores nat for newbies and not so newbies at DEF CON 9, examining nat-traversal and practical defenses.

Summary

Architecture and Background

Description from DEF CON 9 Speaker’s Page: NAT For Newbies and Not-So-Newbies: A Tutorial Network Address Translation (NAT) is a cheap and simple method for boosting the effectiveness of your firewall.

Vulnerability Analysis

Properly configured NAT can help hide your internal network structure from outsiders, enforce 'outbound only' connections from internal hosts, and preserve scarce IPv4 addresses.

Exploitation and Demonstrations

This tutorial moves quickly through the basics, discusses a typical NAT configuration, describes NAT in action, enumerates the benefits of NAT, explains several potential pitfalls and shows how to configure DNS to accommodate the translated addresses.

Remediation and Defensive Strategies

Stiefel ("Stee-ful"), B.Sc., MBA, CISSP, MCSE, CCNA, CCSA/E/I, A+, is the Chief Technical Consultant at Information Engine, Inc., a Silicon Valley networking and security consulting firm. Previously, he was the founding Manager of Information Systems at Galileo Technology and was President of the Windows NT Engineering Association.

Related talks

Main Stage·1 hr 5 min

  • DEF CON
  • Blue Team
  • Date: Jul 2001
  • Location: Las Vegas

K2

K2 examines description from DEF CON 9 Speaker’s Page: Polymorphic shellcode API Polymorphism has been around for years in the form of virus attacks.

nat-traversalnetwork-address-translationfirewalls+1