
Using roughtime as a “cryptographic notary” - Merovius
https://blog.merovius.de/2018/10/18/using-roughtime-as-a-cryptographic-notary.html
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ur-whale
Doesn't the bitcoin blockchain provide the same service roughtime does, and
without the centralized authority (cloudflare in this case) problem?

As in : hash your doc, create a TX with that hash somewhere in it, sending
money to yourself, and once the TX is on chain, the block hash is your
timestamp.

The downside are the fees, and the 10mn delay, of course.

[edit]: now that I'm reading about roughtime, I see that the intent is
completely different (secure clock sync). However, if the plan is to use
roughtime for notarization of documents, I think my remark stands.

source:
[https://blog.cloudflare.com/roughtime/](https://blog.cloudflare.com/roughtime/)

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CiPHPerCoder
> Doesn't the bitcoin blockchain provide the same service roughtime does, and
> without the centralized authority (cloudflare in this case) problem?

Oh god, I can only imagine the horror of trying to use Bitcoin as a public
notary service.

The whole point of an append-only data structure is that you can replicate it
and if someone's node is being dishonest, they cannot do so silently.

You'd be better off with something like Trillian (and/or Certificate
Transparency; see
[https://wiki.mozilla.org/Security/Binary_Transparency](https://wiki.mozilla.org/Security/Binary_Transparency)
for more).

I wrote something in this vein called Chronicle:
[https://github.com/paragonie/chronicle](https://github.com/paragonie/chronicle)

Main selling point? It's not a blockchain, but it solves a lot of the problems
that cause people to point to blockchain solutions.

My goal with Chronicle is to ween the industry off of poorly thought-out
blockchain projects by demonstrating that they don't need a blockchain after
all.

~~~
ur-whale
>you'd be better off with something like Trillian

Isn't Trillian just a simple Merkle tree implementation?

And if so, how does it solve the decentralization part?

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CiPHPerCoder
Is decentralization necessarily a desirable trait of such a system?

When you throw that in the mix, you sacrifice either security or efficiency.

I'd rather have a centralized system (single writer) with decentralized
mirrors (notaries) that exploit the fact that cryptoraphic ledgers are append-
only and totally transparent to solve a lot of engineering problems than a
slow, energy-sucking blockchain.

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bjtitus
I was working on something similar to add in to Perkeep. Any reason you
decided not to use Google's Go implementation?
[https://roughtime.googlesource.com/roughtime/+/master/go/pro...](https://roughtime.googlesource.com/roughtime/+/master/go/protocol/)

~~~
haxton
The last sentences in the article:

> It also comes with a client implementation of the roughtime protocol in Go -
> initially I was not aware that there already was a Go implementation, but
> that also is not go-gettable. Either way, it was fun to implement it myself
> :)

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Mizza
I love cryptographic/data notaries, I'm glad other people think about them.
Thanks for the PoC!

I thought I invented them when I sketched this PoC a long time ago:

[https://github.com/Miserlou/CitizenMediaNotary](https://github.com/Miserlou/CitizenMediaNotary)

but blockchains blew up since then and made my design irrelevant.

