Networking / RFC

This article explains how Windows tracert estimates hops using TTL and ICMP Time Exceeded, including how to interpret the results for troubleshooting.

Learn how to interpret the HTTP response displayed by curl -I in the order of Status, Content-Type, Content-Encoding, Cache-Control, and Content-Length. This is a practical approach that also helps verify gzip compression in Nginx.

Connect to localhost using TcpClient and send an HTTP/1.1 GET request as a string. Observe the differences between the HTTP and TCP layers on a single PC.

A practical look at comparing A and AAAA records using Resolve-DnsName for production tasks.

We review the first 3 items to check in the DevTools Network panel when a web page is slow, tailored for practical use.

Send HEAD and GET requests to the same URL using curl and read-only observe the differences in status and headers.

Use curl --resolve to temporarily replace only the connection IP for a single request, without modifying the operating system's hosts file or DNS.

Observe DNS, connection, time to first byte, and total time separately.

Observe public DNS information in read-only mode using PowerShell.

Send ETag and If-None-Match using curl, and observe HTTP conditional requests through the difference between 200 and 304.