The CAP TheoremThe trade-off every distributed system makes, stated precisely.ComputingA distributed system cannot be simultaneouslyconsistent and available while partitioned.Consistency · Availability · Partition tolerance — pick 2CP — consistent, partition-tolerantRefuse requests rather than serve stale dataBanking; most relational clusters.AP — available, partition-tolerantServe possibly stale dataDNS, shopping carts, Cassandra.CAOnly on a single nodeNetworks partition; you cannot opt out.THE COMMON MISTAKEReading it as a permanent choice between all threeIt is what happens during a partitionWithout a partition a system can be both consistent and available. CAPdescribes the failure mode, not normal operation.PACELC extends it: else — when there is no partition, the trade isbetween latency and consistency.The CAP Theoremlearnposters.com
The CAP Theorem — printable computing wall chart from LearnPosters. Free vector PDF, US Letter and A4.

What’s on the The CAP Theorem poster

The rule, 3 worked examples, and the mistake everyone makes.

PACELC extends it: else — when there is no partition, the trade is between latency and consistency.

Questions about the The CAP Theorem poster

What’s on the The CAP Theorem poster?
The rule, 3 worked examples, and the mistake everyone makes. A distributed system cannot be simultaneously consistent and available while partitio…; Consistency · Availability · Partition tolerance — pick 2; CP — consistent, partition-tolerant = Refuse requests rather than serve stale data; AP — available, partition-tolerant = Serve possibly stale data; CA = Only on a single node; Common mistake: Reading it as a permanent choice between all three → It is what happe…. PACELC extends it: else — when there is no partition, the trade is between latency and consistency.
Who is the The CAP Theorem poster for?
The CAP Theorem belongs to the Computing section rather than to a school year, because computing is not something one grade owns. Anyone learning data can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the The CAP Theorem poster?
The choice only appears during a network partition. The rest of the time you get both. A wall chart earns its place by being glanceable from where the work is happening, so The CAP Theorem belongs on the wall where that computing work actually happens, within glancing distance, rather than filed away.
What other posters go with The CAP Theorem?
ACID, Choosing a Chart and Correlation & Causation sit alongside The CAP Theorem in the Computing section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.ACIDChoosing a ChartCorrelation & Causation
Is the The CAP Theorem poster free to download and print?
Yes. The CAP Theorem downloads as a free PDF with no account, no email and no watermark, like everything else in the Computing section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the The CAP Theorem poster print at?
The CAP Theorem is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of The CAP Theorem loses nothing.Printing guide

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