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Cisco CCNP Enterprise core exam (ENCOR) 350-401 v1.2 · Domain 1: Architecture

QoS components: classification and marking (DSCP, CoS), policing, shaping, queuing (CBWFQ, LLQ), WRED

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Last reviewed September 25, 2026 · Leer en español

Quality of service (QoS) is a set of tools that decide which traffic gets priority when a link is congested. It cannot create bandwidth, but it can make sure voice and video, which are sensitive to delay, jitter and loss, get served before bulk transfers. ENCOR focuses on the building blocks and on the difference between them.

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