QoS

Quality of Service, the toolkit for keeping latency-sensitive traffic flowing predictably across crowded networks. Articles tagged QoS cover classification and marking (DSCP, CoS), MQC, queueing (LLQ, CBWFQ), policing, shaping, and voice and video treatment in SD-WAN and wireless.

10 posts

QoS

Cisco MQC (Modular QoS CLI): The Operator's Walkthrough

The Cisco MQC three-construct model (class-map, policy-map, service-policy) covers every QoS feature on IOS, IOS XE, and IOS XR. The grammar, common actions, hierarchical policies, and verification.

Apr 25, 2026 6 min read

QoS

DSCP and IP Precedence Explained Byte by Byte

DSCP is the 6-bit Layer 3 marking that drives modern QoS. The byte format, the standardized PHBs (CS, AF, EF), Cisco's DSCP-to-CoS-to-MPLS-EXP mapping, and trust boundary discipline.

Apr 25, 2026 7 min read

Wireless

C9800 QoS Configuration: Auto QoS, DSCP Mapping, and Wireless Profiles

Without proper QoS, wireless becomes best-effort and business traffic suffers. A Cisco C9800 QoS guide covering 802.11e, DSCP mapping, Auto QoS profiles, and wireless policies for voice, video, and critical apps.

Apr 5, 2026 12 min read

VLAN

Configuring Voice VLANs on Cisco Switches for IP Phones

Voice VLANs let a single access port carry both data traffic from a PC and voice traffic from an IP phone — each in its own VLAN with its own QoS treatment.

Apr 1, 2026 7 min read