IPsec

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IPsec

• INTERNET PROTOCOL SECURITY

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Typical ways of securing

• Block If you dont want any traffic between
  certain devices or networks.
• Permit If you want to allow traffic between
  certain devices or networks.
• Authenticate If you want traffic only if the two
  devices know and accept each other.
• Tamperproof If you want to make sure that the
  traffic has not been tampered with.
• Encrypt If you want to hide the traffic.

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What is IPsec?

• Set of IPsec protocols and services
• Provides various security services for traffic at
  the IP layer the network layer
• These security services include
• Authentication we are who we say we are
• Integrity the data has not been tampered with
• Confidentiality the data cannot be seen by
  others

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What is IPsec? (2)

• IPsec is composed of three main protocols
• Authentication Header (AH)
• Integrity, anti-replay
• Encapsulating Security Payload (ESP)
• Integrity, anti-replay, confidentiality
• Internet Key Exchange (IKE)
• Cryptographic Infrastructure provides keying and
  negotiation.

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Authentication Header
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Encapsulating Security Payload (ESP)
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IKE
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MODES

• IPsec Operates in two modes
• Tunnel Mode
• It is established between gateways or
  between end-station and a gateway
• Transport Mode
• It is established between
  end-stations or between end-station and a gateway
  if gateway is treated as a host.

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Modes of IPsec
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Transforms sets

• A transform set is a combination of individual
  IPSec transforms designed to enact a specific
  security policy for traffic.
• Mechanism for payload authenticationAH transform
• Mechanism for payload encryptionESP transform
• IPSec mode (transport versus tunnel)

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Algorithms in IPsec

• DES Algorithm
• Triple DES Algorithm (3DES)
• Encryption of packet data.
• Diffie-Hellman (D-H)
• Rivest, Shamir, and Adelman Signatures (RSA)
• public-key cryptographic system used
  for authentication
• Message Digest 5 (MD5)
• Secure Hash Algorithm 1 (SHA-1)
• Secure Hash Algorithm 1 (SHA-1) is a hash
  algorithm used to authenticate packet
  data
• Internet Key Exchange (IKE)
• IKE is a hybrid protocol
• Certificate Authorities (CA)

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Conclusion

• IPsec supports secure communication over Internet
  Protocol.
• Authentication,
• Confidentiality,
• Data integrity,
• Anti Replay Protection.