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Cisco CCNP Enterprise core exam (ENCOR) 350-401 v1.2 · Domain 3: Infrastructure

Spanning tree: RSTP and MST, port roles, root placement, BPDU guard, root guard, loop guard

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Last reviewed September 25, 2026 · Leer en español

Redundant Layer 2 links create loops, and Ethernet frames have no TTL, so a loop causes broadcast storms and MAC table instability that can take down a network in seconds. Spanning Tree Protocol (STP) prevents loops by electing a root bridge and blocking redundant ports. ENCOR focuses on the faster modern versions and the protection features.

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