Bandwidth Budget Calculator MicroSim¶
Learning Objective¶
Estimate the total bandwidth cost of an xAPI deployment by adjusting per-statement size, frequency, batch size, and concurrent learner count.
- Bloom Level: Apply
- Bloom Verb: Estimate
- Library: HTML/JS
Specification¶
The full specification below is extracted from Chapter 9: Bandwidth Optimization, Offline Queues, and Service Workers.
Type: micro-sim
**sim-id:** bandwidth-budget-calculator-microsim<br/>
**Library:** p5.js<br/>
**Status:** Specified
**Learning objective (Bloom — Applying):** Estimate the total bandwidth cost of an xAPI deployment by adjusting per-statement size, frequency, batch size, and concurrent learner count.
**Layout:** 2/3 (left) input controls + 1/3 (right) live output panel.
**Controls:**
- Slider: Per-statement payload size (500 – 3000 bytes, default 1200)
- Slider: HTTP overhead per request (300 – 1500 bytes, default 700)
- Slider: Statements per learner per session (5 – 200, default 45)
- Slider: Session duration in minutes (5 – 120, default 20)
- Slider: Concurrent learners (1 – 1000, default 30)
- Slider: Batch size — statements per POST (1 – 50, default 1; demonstrates the impact of batching)
**Right panel output:**
- Total bytes per learner per session
- Total bytes for the cohort
- Average bytes per second during the session
- Comparison bar showing this vs. one of three reference loads ("classroom WiFi headroom", "10 Mbps cellular tether", "1 Gbps campus link")
- A green/yellow/red headroom badge based on the reference load
**Interaction:**
- Adjusting any slider re-computes all outputs in real time
- Preset buttons across the bottom: "Reading-only chapter", "Interactive math chapter", "Simulation-heavy physics chapter", "30-student assessment window"
**Default canvas:** 1000×600px, responsive.
Implementation: p5.js for the sliders, layout, and dynamic computations; HTML overlay for the output panel.