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QoS Queue Sizing Calculator

Calculate bandwidth allocation, queue depth, and serialization delay per traffic class

Total interface bandwidth where QoS policies are applied.
Mbps
Priority queue for voice (EF/DSCP 46). Cisco recommends max 33% for priority queue.
%
Bandwidth for video conferencing and streaming (AF41/DSCP 34). Typically 10-30%.
%
Business-critical apps: ERP, databases, transactional traffic (AF31/DSCP 26).
%
Default class for general internet, email, non-critical apps (DSCP 0).
%
Max burst interval in ms. Determines temporary rate overshoot allowance. Typical: 50-200ms.
ms

QoS Queue Configuration

Link Summary

Total Allocated BandwidthMbps
Allocation Percentage%
Unallocated (Headroom)Mbps
MTU Serialization (1500B)ms
References: Cisco QoS Design Guide, RFC 2474 (DiffServ), RFC 3246 (Expedited Forwarding). Queue depth Bc = CIR x Tc. Serialization delay = frame_size_bits / link_speed_bps.