The life of a request
From the moment a request leaves the browser to the moment the response lands: name resolution, the handshakes, the edge, the front door, the cluster, the work, and the way home. Click any box with a ＋ to go deeper.
The life of a request
topicSeven things happen to every request, in order, and each one is a world of its own.
Type an address and press enter, and the browser does not "call the server". It resolves a name into an address, opens and secures a connection, and hands the request to an edge that is almost never the machine you think you are talking to. That edge forwards it to an origin's front door, which forwards it into a private network, where it hops between services until something does the actual work. Then the whole journey runs backwards.
Each box below is one of those acts. The map shows the basic flow; every box marked ＋ opens into its own map, and those open into more. Read the prose at each stop, or use "read it straight through" to walk the whole tree as one article.
One idea holds the entire trail together: at every layer, something is pretending. The IP address pretends to be one machine and is many. The connection pretends to be a pipe and is packets. The edge pretends to be the origin. The cluster IP pretends to be a service and is iptables rules. Understanding a layer means finding out what it pretends, and what that pretence costs when it leaks.
a ＋ goes one level deeper — click the box
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