DAG for DUMMIES: how to stop worrying and love the crypto

enxo rizzo
Sep 5, 2018 · 4 min read

Same old same

The other day i remembered an old, funny story. Back in 2008–9? i found some little site and couldn’t find out what exactly it did. Something with code? storing projects in cloud? well, anyways, it was something called github.com

There i was, looking at buttons, reading tutorials, muddling about what exactly a git repo was. A little bit later i go, ok, some weird thing with code and backups and versioning, just let me check another fad. And off i went to twitter, or something.

my understanding of git back at the time. yup.

It was only after a couple of years that out of necessity from work i started to use git and remembered that i already had an account at github. And started my painful learning curve of git-fu . It was shameful, really, a CS major with a backpack full of algebra, set theory, design patterns and whatnot, and that thing looked alien, completely counter-intuitive.

It was only after GUI tools showed up that i could make any sense of what really is something simple, when looked with the proper glasses. If you want to grill a steak, add salt (and garlic). Put salt on steak. Put steak on grill. Done. DO NOT go study mammal biochemistry or thermodynamics.

How to cook a DAG

So, we’ve been getting lots of hype/fud/news about crypto projects based on DAGS. IOTA, Byteball, NANO, Hedera. Hash graphs, side-chains, gossip protocols. Hacks, Byzantine fault tolerant flaws. Trying to understand it all is a mess. Or a tangle.

The general idea for a crypto DAG chain is that a new node comes from previous nodes. Each node is signed with a hash to verify that it’s not false. All nodes can be travelled back until some origin node. And add some specific context rules (a node cannot be it’s own parent, nodes have timestamps, insert-more-useful-rules-here).
These rules need some care put into them, and implementation must be flawless, since the DAG carries economic value, but those concepts are outside the chain itself. Say, the NANO or IOTA networks don’t actually need to know their own traded value for USD. And if they need, that’s what oracles were invented for ;)

But wait a minute. I have looked at this thing already. Forget all the buzzwords two paragraphs before. I have looked at it a lot. This is just how git works. Let’s see:

  • a commit must be made from other previous commits. check
  • a string of commits defines a whole branch/tree/repo. check
  • each commit can be travelled back to the origin. check
  • each commit is hashed, to secure the repo and find any errors. check
Two graphs. One is a crypto thing, the other is a code thing

If we forget for a moment that these two graphs come from very different tools/generators, the structure is not that different, right? i could even be fooled into thinking the hashes in the first picture are blockchain transactions or something. The underlying idea and topological structure are pretty much the same thing.
We had DAG chains working for years and didn’t even know it :)

One DAG, medium-rare, please

So, the steak is ready. From all the million gihub users, i bet not one percent has actually needed, or wanted to verify the math behind the git inner workings. It just works, and it’s good. Depending on the tutorials found, it may, or not, have been easy to grasp the toolbox to use git. But once we get to grok it, we just git away, it becomes painless.

Exactly the same with crypto DAGs. Each project may or may not succeed, and a lot of success factors will be external, economics, marketing, alliances, all the human stuff around each project. With the added weight of required/flawless economical security for such a DAG, with all the millionaire crypto hacks and such, the bar is high, yes it is.

But, if anyone says it’s a fad, an unproved idea, it’s too complicated to work, i just have one answer:

Linus. Git. nuff said.

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade