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InfiniBand: from SDR to XDR
Thirty years of a technology almost nobody explains, and the architecture decision it forces on you
Read the entry → Updated Aug 22, 2026
EPISTEME is where we write down what we know, and how we came to know it. Every entry carries its sources, its date and the technical review that cleared it. Nothing enters the corpus because it sounds good. It enters because it can be justified.
The corpus is organized by the six Hexa domains, from the photon to exascale, and by depth of reading. Some entries settle a definition in one screen. Others walk the full argument, with benchmarks, topologies and thermal budgets. Both are here, and both are labeled.
Thirty years of a technology almost nobody explains, and the architecture decision it forces on you
Five layers decide whether the link comes up, comes up at half, or does not come up at all, and the two that cost the most money are the ones that never report an error
No entry matches this search.
Verifiable fact, with a datable and auditable source: a vendor specification, a published benchmark, a standard, a project we delivered. If the source falls, the entry falls with it.
Reading, projection, architectural judgment. Legitimate and useful, but ours, not the world's. We mark it so you can disagree with it knowing exactly what you are disagreeing with.
