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Juniper Networks Certified Associate, Junos (JNCIA-Junos) JN0-106 · Domain 1: Networking fundamentals

Ethernet frames, MAC addresses (48 bits, OUI) and the MAC learning/flooding process

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Last reviewed September 25, 2026 · Leer en español

Ethernet is the Layer 2 technology on almost every LAN (local area network) you will touch. Data is carried in frames, and every frame names its sender and receiver with MAC addresses. Knowing the frame layout and how switches learn addresses helps you read show ethernet-switching table output and troubleshoot why traffic is or is not reaching a host.

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