Layer 2: Data Link Layer

Overview: Layer includes issues related to the transmission of data frames between two nodes connected by a physical layer

Technologies in Scope: IEEE 802.3, ARP

• Does the device’s mac address show up in the mac address table of the switch?
  • MAC Address Notes
    • Device manufacturers reserve the beginning 6 letters in a range of mac addresses. These are known as (OUI): Organizationally unique identifier.
    • Axis is the only manufacturer authorized to sell devices with the mac addresses beginning in the following 6 hexadecimal characters:
      • B8:A4:4F
      • AC:CC:8E
      • 00:40:8C
    • When scanning networks or issuing commands, we know that any devices with these beginning characters are Axis devices.
    • Bad actors could spoof these mac addresses during an attack but that is outside the scope of this guide.

• Does the switch show power applied to the switchport? (be wary of injectors)
• Does the switchport show link status? Does the switchport show PoE status?
• Does the switch show enough total power budget to power the device based on device datasheet?
• Does the switch provide enough power per port? (Example: 802.3at camera on an 802.3af port)

• Confirm switch capabilities to device datasheet to confirm power allocation​
  • Never use passive PoE for an Axis device under any circumstance​
  • Be wary of switches that only offer higher power on certain ports and not all ports, especially on older switches

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