TCP Congestion Control

Simulate TCP Reno and Tahoe. Watch the congestion window grow, hit ssthresh, and react to packet loss.

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Cwnd Over Time (Simulation)
X-Axis: Time (RTT)   |   Y-Axis: Congestion Window (MSS)
Configuration & Metrics
CURRENT PHASE: SLOW START
CWND (MSS)
1.0
SSTHRESH
16
PACKETS SENT
0
PACKETS LOST
0
What's happening?

Slow Start: cwnd doubles every RTT. (Exponential growth).

Congestion Avoidance: Once cwnd >= ssthresh, cwnd grows by 1 MSS per RTT. (Linear growth).

Triple Dup ACK: Indicates mild congestion. ssthresh = cwnd/2. TCP Reno enters Fast Recovery (cwnd = ssthresh + 3). TCP Tahoe drops cwnd to 1.

Timeout: Indicates severe congestion. cwnd drops to 1 MSS, ssthresh = cwnd/2, restart Slow Start.