networking – text/plain

Captive Portals

When you join a public WiFi network, sometimes you’ll notice that you have to accept “Terms of Use” or provide a password or payment to use the network. Your browser opens or navigates to a page that shows the network’s legal terms or web log on form, you fill it out, and you’re on yourContinue reading “Captive Portals”

Chromium’s DNS Cache

From the mailbag: Q: How long does Chromium cache hostnames? I know a user can clear the hostname cache using the Clear host cache button on about://net-internals/#dns, but how long it will take for the cache to be removed if no manual action is taken? After changing DNS records on my server, nslookup from aContinue reading “Chromium’s DNS Cache”

Web Proxy Auto Discovery (WPAD)

Back in the mid-aughts, Adam G., a colleague on the IE team, used the email signature “IE Networking Team – Without us, you’d be browsing your hard drive.” And while I’m sure it was meant to be a bit tongue-in-cheek, it’s really true– without a working network stack, web browsers aren’t nearly as useful. BackgroundContinue reading “Web Proxy Auto Discovery (WPAD)”

Analyzing Network Traffic Logs (NetLog json)

Previously, I’ve described how to capture a network traffic log from Microsoft Edge, Google Chrome, and applications based on Chromium or Electron. In this post, I aim to catalog some guidance for looking at these logs to help find the root cause of captured problems and otherwise make sense of the data collected. Last Update:Continue reading “Analyzing Network Traffic Logs (NetLog json)”

Capture Network Logs (NetLog) from Edge and Chrome (and Electron and WebView2)

Problems in accessing websites can often be found and fixed if the network traffic between the browser and the website is captured as the problem occurs and the resulting log file is shared with engineers. This short post explains how to capture such log files. Capturing Network Traffic Logs If someone asked you to readContinue reading “Capture Network Logs (NetLog) from Edge and Chrome (and Electron and WebView2)”

The Pitfalls of EventSource over HTTP/1.1

While there are many different ways for servers to stream data to clients, the Server-sent Events / EventSource Interface is one of the simplest. Your code simply creates an EventSource and then subscribes to its onmessage callback: Implementing the server side is almost as simple: your handler just prefaces each piece of data it wantsContinue reading “The Pitfalls of EventSource over HTTP/1.1”