Cracking the Case: How We Captured and Analyzed DIAL Traffic in a Recent Case

In the world of technology, some of the most interesting innovations work silently in the background, invisible to the end user. One such example is the Discovery and Launch (DIAL) protocol, the unseen handshake that allows video streaming apps like Netflix and YouTube to cast videos from your phone straight to your TV.

Built on top of HTTP and HTTPS, DIAL adds the extra details needed for the two devices to communicate streaming commands. And like most network protocols, it leaves behind a trail — traffic that can be captured, analyzed, and used to reveal exactly how the devices are talking to each other.

In a recent patent infringement case, our client needed to understand the communication between the app and the TV. Our job: capture and analyze DIAL traffic to uncover technical evidence not available from public sources.

How We Approached the Analysis

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Step 1: Capturing the Traffic

We began with an open-source HTTP debugging tool to intercept HTTP and HTTPS traffic. A test laptop, running the tool, was configured as a proxy server. All communication from the mobile device was routed through this proxy in a controlled man-in-the-middle setup.

Because the app used HTTPS, the packets were encrypted — meaning we had to find a way past that encryption barrier to view the data.

Step 2: Breaking Through Encryption

To decrypt the traffic, we installed the proxy server’s root certificate on the mobile device, tricking it into trusting the proxy. This allowed the device to send encrypted HTTP requests to the proxy using its public key. The proxy then decrypted them with its private key, exposing the communication in clear text.

With this step, what was once hidden was now visible for analysis.

Step 3: Extracting the Evidence

The captured traffic revealed session IDs, commands, nonces, and other control data — the digital fingerprints of how DIAL worked behind the scenes. Without touching the source code, we gained a clear view of the device-to-device protocol in action.

These insights proved invaluable to the client’s legal team, providing hard technical evidence to evaluate the infringement claims without relying solely on formal discovery.

Why This Matters

Bottom line: capturing and analyzing network packets can be a powerful tool in patent litigation. It turns invisible communications into actionable insights — sometimes the difference between winning and losing a case.