As AlvaLinks’ CTO, I’ve spent countless hours troubleshooting live video feeds-some in the calm of the lab, many in the chaos of a real broadcast. When it comes to SRT (Secure Reliable Transport), it’s a powerful protocol that can handle rough network conditions-until it can’t.

The reality is this: SRT doesn’t just “fail” out of nowhere. It usually collapses because one or more measurable conditions spiral out of control. Let’s take a closer look at the four main culprits, their root causes, and how they take down a feed.

Excessive Packet Loss

Root cause: Congestion on a shared network segment, faulty network hardware, or wireless interference.

Impact: Each lost packet means missing pieces of the video stream. While SRT can request retransmissions, too much loss overwhelms its recovery window, causing visible artifacts, freezes, or total feed drop.

Example: A distribution feed to the office loses 12% of packets during a sudden spike in crowd Wi-Fi usage-SRT’s retransmission queue can’t keep up, and the feed pixelates into useless noise.

Excessive Jitter

Root cause: Inconsistent packet delivery timing due to unstable routing paths, queue delays, or CPU contention in the network devices.

Impact: Even if packets aren’t lost, large variations in arrival times force SRT to buffer more, increasing latency and risking playback stalls.

Example: A live sports feed sees jitter spike from 3ms to 90ms when an upstream router hits a CPU overload-latency balloons and the audience sees a 2-second freeze.

Increased RTT (Round-Trip Time)

Root cause: Suboptimal routing, transient congestion, or peering issues between ISPs.

Impact: A higher RTT slows down acknowledgment and retransmission cycles, meaning recovery from any loss takes longer and the buffer may underrun.

Example: During a cross-continent feed, RTT jumps from 120ms to 300ms after a routing change-suddenly SRT is playing catch-up on every frame.

ARQ Storm Change

Root cause: A burst of packet loss triggering mass retransmission requests (Automatic Repeat reQuest), often amplified by RTT increases.

Impact: The retransmission traffic itself becomes a flood, further congesting the link and making recovery nearly impossible.

Example: An unexpected router failure forces traffic over a congested backup path-packet loss hits 8%, RTT doubles, and the ARQ requests themselves choke the network.

Where AlvaLinks Comes In

This is exactly why we built the AlvaLinks SRT Probe-to see these storms coming before they capsize your feed.

– Real-time loss and jitter analysis: Detects anomalies within sub-second resolution so you can react before the viewer notices.
– RTT trend tracking: Pinpoints when a route change or upstream slowdown is starting to impact your recovery window.
– ARQ storm early warnings: Flags retransmission bursts before they snowball into a total breakdown.
– Root cause visibility: Whether it’s a local interface drop, an ISP congestion point, or a faulty encoder NIC, the probe makes the problem visible.

Example in action:
During a breaking news event, one broadcaster using our SRT probe saw early warning of jitter spikes on their primary path. Within seconds, operations switched to a backup route-viewers saw uninterrupted coverage, while the root cause (an overloaded router in a remote PoP) was fixed without crisis.

In SRT transport, survival isn’t about luck-it’s about visibility. If your broadcast relies on SRT and you want to truly look into its “eye” before the storm hits, let’s talk. I’m always open to sharing war stories, strategies, and practical fixes.

📩 Contact me directly to explore how we can bulletproof your feeds.
– Adi Rozenberg, CTO, AlvaLinks