Fundamentals of Network Security

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Fundamentals of Network Security

• Ravi Mukkamala
• SCI 101
• October 6, 2003

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Goals

• Authentication Are you who you claim to be?
• Authorization Are you authorized to do this?
• Integrity Is the message what the user has sent?
• Confidentiality Can one read this?
• Availability (Denial-of-service attacks)
• Accountability (Non-repudiation) How can we
  prove that the message was indeed sent by the
  sender?

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Tools

• Cryptography Symmetric and asymmetric
• Symmetric A single secret key for encryption and
  decryption
• Asymmetric A key pair Public key and private
  key sender encrypts using key owners public
  key key owner decrypts using corresponding
  private key

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Tools (contd.)

• Encryption/Decryption algorithms
• Digital signatures Sender uses private key to
  generate a special tag and appends to the
  message. Receiver cross checks the integrity by
  rechecking with the senders public key. (Third
  party can resolve a dispute)
• Message authentication code (MAC) Secret key,
  when applied on a message, gives MAC. The
  receiver can regenerate the MAC and ensure the
  integrity of the message
• Cryptographic hash functions

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Network security
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Network filters

• Firewalls
• Routers

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Public-key Infrastructure

• CA certificate authority
• RA registration agent
• Issuance and revocation of certificates
• Trust points
• Certificate and path verification
• Delegation

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References

• www.cs.odu.edu/cs472
• www.cs.odu.edu/cs772
• Network Security Private Communications in a
  Public World,  2nd edition, 2002,  C. Kaufman, 
  R. Perlman, and  M. Speciner, Prentice-Hall.
• Cryptography and Network Security Principles and
  Practice (3rd Edition) by William Stallings
• Hacking Exposed Network Security Secrets
  Solutions, Fourth Edition by Stuart McClure, et
  al