Layer 2: Data Link

The Data Link Layer provides node-to-node data transfer and handles error correction from the physical layer.

Key Points
  • Breaks data into frames for transmission
  • Manages flow control and error checking
  • Handles access to the physical medium
  • Includes two sublayers: Logical Link Control (LLC) and Media Access Control (MAC)
  • Provides physical addressing (MAC addresses)
  • Implements error detection and correction
RFC References
Attacks

  • MAC Spoofing: Attacker changes the MAC address of their device to impersonate another device on the network.

  • ARP Poisoning: Manipulating Address Resolution Protocol (ARP) tables to redirect traffic, enabling man-in-the-middle attacks.

  • Switch Flooding: Overwhelming a switch with fake MAC addresses to force it into hub-like behavior, potentially exposing traffic.