Security Protocol

TLS - Transport Layer Security

  • standard protocol for internet security
  • enables privacy and data integrity between two communicating applications.
  • Based on Secure Socket Layer protocol (SSL v.3)
  • complies with CIA

IPSec

A framework of open standards that incorporates cryptographic secure services in IP networks. A suite of protocols used to secure IP communications by authenticating and encrypting each IP packet in a data stream. Commonly used for creating secure VPN connections, ensuring confidentiality, integrity, and authentication of data sent over public or private networks.

IPSec modes

  • Tunnel Mode : between gateways, end-host to a gateway, or when gateway acts as a proxy for the hosts behind it.
  • Transport mode : end-to-end security between hosts, e.g. between end-hosts, end-hosts and a gateway that acts as a host (vulnerable to eavesdroppers).

Negotiation Phase

Phase 1

  • Establishment of SAs between two entities
  • Two modes: Main or Aggressive
  • 4 techniques for authentication:
  • Uses ephemeral Diffie-Helman (EDH) to establish session key
  • Provides perfect forward secrecy Phase 2
  • Establishment of SAs for ESP/AH protocols
  • One mode : Quick Mode

ISAKMP - Internet Security Association & Key Management Protocols

A protocol used for establishing, negotiating, modifying, and deleting Security Associations (SAs) in IPsec. Provides a framework for key exchange and authentication, ensuring secure communication between devices in a network.

  • enables the use of SA in IPSec The ISAKMP protocol (RFC 2408) defines procedures for:
  1. Authentication
  2. Creation/Management of SAs
  3. Key generation /key transport techniques
  4. Mitigation of threats (e.g. DoS attacks, replay attacks)

SA - Security Association

  • A set of security parameters established between two network entities to define how they will secure communications, typically used in IPSec.
  • Specifies encryption, authentication algorithms, and key exchange methods to ensure secure data transmission.

IKE - Internet Key Exchange

Protocol for establishing secure communication channels, often used in VPNs. Uses two phases:

  • Phase 1 - sets up a secure channel
  • Phase 2 - negotiates encryption and authentication for data transfer.

ESP - Encapsulating Security Payload

payload encryption ensuring authenticity, integrity and confidentiality.

  • does not provide integrity and authentication for the ENTIRE packet.

AH - Authentication Header

Protocol used in IPsec to provide data integrity and authentication for IP packets. AH ensures that packets are from a legitimate source and have not been altered in transit by adding a cryptographic checksum to the packet header and payload.