LatencyLab — Internet Physics Playground

Network Parameters

Round-Trip Time 80 ms

NY→London physics floor ≈ 70 ms

Packet Loss 0.0%

WiFi ~0.1% · 4G ~0.5–2% · Bad >5%

Jitter (σ) 5 ms

Variance in arrival. Kills real-time media.

Bandwidth 10 Mbps

Link capacity (not throughput)

Initial CWND 10 pkts

TCP congestion window. Linux default: 10

Transport Protocol

Live Metrics

Throughput

— Mbps

Eff. Latency

— ms

Retransmits

—

Queue Depth

— pkts

PACKET FLOW

DATA ACK LOST RETX

💡 WHY THIS HAPPENS

Pick a scenario and hit Run to see a live explanation of what's happening on the wire.

REQUEST TIMELINE ms

BANDWIDTH UTILIZATION Mbps

RETRANSMISSION BURSTS pkts

QUEUE BUILDUP pkts