Fast Recovery
Fast Recovery avoids dropping back to slow start after a fast retransmit; instead it halves cwnd and keeps sending, preventing a throughput cliff.
Purpose
It restores throughput quickly after mild loss rather than restarting from slow start, speeding up recovery.
Mechanism
After a fast retransmit, ssthresh = cwnd/2 and cwnd = ssthresh + 3 (three subsequent segments already acknowledged), and new segments keep being sent. Each further duplicate ACK increments cwnd by 1 and allows another send; a fresh ACK restores cwnd = ssthresh and enters congestion avoidance.
Use cases
- Fast TCP congestion recovery
- Throughput preservation
- Congestion control
Related tools
HTTP Status Codes
Reference table of common HTTP status codes (1xx-5xx) with names, categories, and descriptions. Free, private, and 100% client-side. TOOL
URL Parser
Parse a URL into its components: protocol, host, path, query, hash, port, username, and password. Free, private, and 100% client-side. TOOL