Protocols

In Diagnosing Video Stuttering Over TCP, we built a diagnostic framework—identifying zero-window events (receiver overwhelmed) versus retransmits (network problems). In The TCP Jitter Cliff, we discovered that throughput collapses unpredictably when jitter exceeds ~20% of RTT, and the chaos zone makes diagnosis treacherous.

The conclusion from both posts is clear: TCP is inappropriate for delay-sensitive streaming. Its guaranteed-delivery model creates unbounded latency during loss recovery. When a packet is lost, TCP will wait—potentially forever—rather than skip ahead. For a live video frame or audio sample, arriving late is the same as not arriving at all.

But “don’t use TCP” isn’t a complete answer. What should you use? The protocol landscape for delay-sensitive data is vast—spanning media streaming, industrial automation, robotics, financial messaging, and IoT. Each protocol answers the fundamental question differently.

This is a quick-reference list of protocols for applications where data has a deadline, and late delivery is failure—whether that deadline is 10μs (servo loop), 20ms (audio buffer), or 300ms (video call).

For taxonomy, analysis, and context, see When Packets Can’t Wait. This page is just the inventory—a living reference that grows as protocols become relevant to JitterTrap development.