Data Center

Two elephant flows, six trials, six collisions: one uplink carried everything while its twin sat at zero, and every dashboard stayed green. The measured polarization, the four-witness diagnostic chase, and the birthday math production fabrics live with.

Your AI cluster is two networks wearing one badge. One is judged by whether users notice it. The other is judged by whether GPUs wait on it. Frontend vs backend: the traffic, the rules, and how to design the GPU fabric so compute never waits.

Credit-based flow control, a daemon that runs the whole fabric, adapters that hand out pointers into remote RAM, and switches that do math. Every InfiniBand idea an Ethernet engineer should know, demonstrated live on a real InfiniBand fabric.

Every chip in the modern data center exists because one bottleneck got expensive enough to deserve its own silicon. The whole zoo in one sitting: real photos, one table, and a memory trick that makes the differences stick.

Twelve switches become a fabric: loopbacks, /31s, jumbo MTU, and eBGP as the only routing protocol. Plus the promised look inside a vPC leaf pair, and the three-command verification that proves the underlay.