• Most important data link layer standard
  • Capable of running on variety of network media
  • Offers excellent throughput at reasonable cost
  • Most popular network tech used on modern LANs
  • Ethernet II is current standard
  • Adds both header and trailer to payload
    • Creates frame around payload
    • Header and FCS make up 18 byte "frame" around data
  • Data portion of an Ethernet frame may contain 46 - 1500 bytes
  • MTU
    • Maximum transmission unit
    • Largest size that routers in a message's path will allow at network layer
  • Exceptions on Ethernet frame size limitations:
    • On a VLAN can have an extra 4 byte field between source address field and type field
    • Some special purpose networks use proprietary version of Ethernet allowing for a jumbo frame
      • MTU can be as high as 9198 bytes (depends on Ethernet architecture used)

Networking Computer Science