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  1. Security

  2. Myths about Business Risksin the Information Age • Security is only about protecting “things” • We don’t have any information anyone would want • Security problems have never happened here. • Firewalls provide enough security • Technology will solve the security problem • The “enemy” is outside • Our people won’t tolerate tight security • My PC is secure, so I’m secure • The Internet can’t be used for secure communications The Economist and Arthur Andersen

  3. SECURITY: • Deter • Detect • Minimize • Investigate • Recover

  4. Security Risks • Internal • External

  5. Threats • Disaster and breakdowns • Access and disclosure • Alteration or destruction • Improper use

  6. RISK ASSESSMENT • P1 Probability of attack • P2 Probability of success • L Cost of Loss Expected Loss = P1 * P2 * L Minimize Threat Categories

  7. Security Policy Security is always a cost to efficiency. It must be promoted to be effective. • From the top • Before installing hardware • Politically charged

  8. Writing a Security Policy • Assess the types of risks • Identify vulnerabilities • Analyze user needs • Write the policy • Develop change procedures • Plan implementation • Implement

  9. Personnel Risk Background checks Segregation of duties Terminated employees Physical Access Risk Disaster Risk Disaster Recovery Backup/hot sites Integrity Risk Access Risk Availability Risk Infrastructure Capability Denial of service Risk Areas

  10. Integrity Risk Risks associated with the authorization, completeness and accuracy of transactions • User interface • Processing • Error Processing • Interfaces with other systems/databases • Change Management • Data • Privacy • Backup

  11. Access Risk Risks associated with inappropriate access to systems or data • Identification, authentication and nonrepudiation • What you know, what you have, what you are • Encryption (algorithm and key) • Secret key, private/public key • smart cards, hardware tokens • Digital Signature (hashing and public key; encrypt with private key, send with private key, and then decode with public key) • Certification authority and digital certificates • Security Protocols • Firewalls and Guards

  12. Elements of Risk Asset Threat Access

  13. Administrative Controls:Limit the Threat Standards, rules, procedures and discipline to assure that personnel abide by established policies. Includes segregation of functions.

  14. Administrative Controls • Security organization • Audits • Risk assessment • Administrative standards and procedures

  15. Protecting the Assets • Resource management • Disaster recovery • System segregation

  16. Resource Management • Backup planning • Job scheduling • Redundant design • Selective decoupling

  17. Disaster Management • Redundancy and fault tolerant systems • Backups and off site storage • Hot and cold sites • Planning and procedures

  18. Elements of Risk Asset Threat Access

  19. Vulnerabilities • Servers Securing operating systems and applications • Networks Access protection from snooping, attacks, spoofing • Clients and modems User verification for PCAnywhere etc. • Viruses

  20. Operating Systems • UNIX • Novell Netware • Windows and Windows NT

  21. Secure Operating Systems • U.S. Government Certification • A1, B1, B2, B3, C1, C2 (most commercial systems), D • Ease of use • CERT (Computer Emergency Response Team)

  22. Top 12 SecurityRisks 1. Hosts run unnecessary services 3. Information leakage through network service programs 4. Misuse of trusted access 5. Misconfigured firewall access lists 7. Misconfigured web servers 10.Inadequate logging, monitoring or detecting

  23. Top 12 Security Risks 2. Unpatched, outdated or default configured software 6. Weak Passwords 8.Improperly exported file sharing services 9. Misconfigured or unpatched Windows NT servers 11.Unsecured remote access 12.Lack of comprehensive policies and standards

  24. Tools • Firewalls • Network partitioning and routers • Encryption • Testing tools • Consultants

  25. Firewall functions • Packet Filter:Blocks traffic based on IP address and/or port numbers. • Proxy Server:Serves as a relay between two networks, breaking the connection between the two. • Network Address Translation (NAT):Hides the IP addresses of client stations in an internal network by presenting one IP address to the outside world. • Stateful Inspection:Tracks the transaction in order to verify that the destination of an inbound packet matches the source of a previous outbound request. Generally can examine multiple layers of the protocol stack.

  26. Firewall Operation

  27. Firewall Operation 1. A router sits between two networks 2. A programmer writes an access control list, which contains IP addresses that can be allowed onto the network. 3. A message gets sent to the router. It checks the address against the access control list. If address the is on the list, it can go through. 4. If the address isn't on the list, the message is denied access to the network.

  28. Encryption • Keys and key length • Public key/private key • Processing problems • Location • Application • Network • Firewall • Link

  29. Encryption Techniques

  30. How Public Encryption Works 1. Sue wants to send a message to Sam, so she finds his public key in a directory. 2. Sue uses the public key to encrypt the message and send it to Sam. 3. When the encrypted message arrives, Sam uses his private key to decrypt the data and read Sue's message.

  31. Encryption at the Firewall

  32. Authentication • Passwords • “Credit” cards • Biometrics • Isolation • Remote location verification

  33. Biometrics: how it works • Users "enroll" by having their fingerprints, irises, faces, signatures or voice prints scanned. • Key features are extracted and converted to unique templates, which are stored as encrypted numerical data. • Corresponding features presented by a would-be user are compared to the templates in the database. • Matches will rarely be perfect, and the owners of the system can vary a sensitivity threshhold so as to minimize either the rate of false rejections, which annoy users, or false acceptances, which jeopardize security. This offers far more flexibility than the binary "Yes" or "No" answers given by password technologies.

  34. Common biometric techniques and how they rate International Biometric Group, New York as reported in Computerworld, Quick Study: Biometrics, 10/12/98

  35. Security