1. IPsec: Internet Protocol Security Chong, Luon, Prins, Trotter

2. What is IPsec? A collection of protocols for securing Internet Protocol (IP) communications by encrypting and authenticating all IP packets 1 Progressive standard Defined in RFC 2401 thru 2409 Purpose: –To protect IP packets –To provide defense against network attacks 1: From wikipedia.org

3. What is IPsec? (cont) Created November 1998 Created by the Internet Engineering Task Force (IETF) Deployable on all platforms –Windows –Unix –Etc.. Can be implemented and deployed on: –End hosts –Gateways –Routers –Firewalls

4. Protection Against Attacks Layer 3 (network) protection Protects from: –sniffers by encrypting data –data modifications by using cryptography based checksums –identity spoofing, denial of service, application layer, and password based attacks through mutual authentication –man in the middle attacks by mutual authentication and cryptography based keys

5. How IPsec Works Services Protocol Types Key Protection Components Policy Based Security Model Example

6. How IPsec Works: Services Security Properties –Non-repudiation & Authentication Public key certificate based authentication Pre-shared key authentication –Anti-replay Key management Diffie-Hellman Algorithm, Internet Key Exchange (IKE) –Integrity Hash message authentication codes (HMAC) –Confidentiality Public key cryptography

7. How IPsec Works: Protocol Types Authentication header (AH) –Authentication, integrity, and anti-replay –Placed between the IP layer and the transport layer

8. Header Fields Protection

9. How IPsec Works: Protocol Types (cont.) Encapsulating security payload (ESP) –Provides confidentiality in addition to what AH provides –Has: Header Trailer Authentication Trailer

10. Header Fields Protection

11. How IPsec Works: Components IPsec Policy Agent Service Diffie-Hellman Algorithm Internet Key Exchange (IKE) Security Association (SA) –Phase 1 SA –Phase 2 SA IPsec Driver

12. How IPsec Works: Key Protection Key lifetimes Session key refresh limit Perfect forward security (PFS)

13. How IPsec Works: Policy Based Security Rules Filter list Filter actions Policy Inheritance Authentication

14. How IPsec Works: Model Example

15. Practical Implementations LANs, WANs, and remote connections –VPNs for remote access –Dial-up setting to private networks –Where data security is critical Example: Hospital with patient data Businesses with multiple sites

16. Suggested Readings http://en.wikipedia.org/wiki/IPSEC http://www.ietf.org/rfc/rfc2401.txt http://www.webopedia.com/TERM/I/IPsec.html http://www.microsoft.com/windows2000/techinfo/p lanning/security/ipsecsteps.asphttp://www.microsoft.com/windows2000/techinfo/p lanning/security/ipsecsteps.asp Microsoft Windows 2000 Server TCP/IP Core Networking Guide