Return-Path: Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists.linuxfoundation.org (Postfix) with ESMTP id C8C78C0001 for ; Tue, 18 May 2021 10:16:14 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id A42A040246 for ; Tue, 18 May 2021 10:16:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -2.099 X-Spam-Level: X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Authentication-Results: smtp2.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1m3M5BDkG66s for ; Tue, 18 May 2021 10:16:13 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.8.0 Received: from mail-io1-xd2c.google.com (mail-io1-xd2c.google.com [IPv6:2607:f8b0:4864:20::d2c]) by smtp2.osuosl.org (Postfix) with ESMTPS id 4EA05400CD for ; Tue, 18 May 2021 10:16:13 +0000 (UTC) Received: by mail-io1-xd2c.google.com with SMTP id r4so8122559iol.6 for ; Tue, 18 May 2021 03:16:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=i0owgmqjx++N3lAofrgVXvKvHyG2oB4Vs6Br9kG7Tjc=; b=GucokXm+lUWvx8I8Uxf6wL/60d6gmawbNf+UVwfOmTrCxg7LhoeSjlqkGAQl6DCPn0 tAGa5Yno5C4ijJ60SNWtq5MJzPlLUIseXm79P9mWQatwA1M9jA698+XkM8sw6EkHi3+A gKFJlMFXNt17dTsEB+WDbM1KXdFoLuUt3gGjDfZKy5l/gLD8bvvm06uSPG2xqhWRTrIg 5UCYVdiojwwxAMI70ApxzdIZz+WqxbSl/mQGUHv4QoNOMnnR9aKQLudCKZOqnH0fHDZF V6Z0LEogBRM3DQSOzeuY5wVrV7ObUZGAyAJ12NcwTrNeMofi7yhYMUKJd6aAuQguFElj CctA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=i0owgmqjx++N3lAofrgVXvKvHyG2oB4Vs6Br9kG7Tjc=; b=NUSeEqikbJlyDw1pYCN9Ggy7ZwvP3oKEalFuA132HXnXh6/c0UV+yxBozYxMpm6ps0 dst4Eu1uXX8CGjQEhTbGRxULw6LmnAwtXQwKlTZomQD0/4YDoqqXmo9O4A4vTQghVoCd ManbuEAu1ieKSPiHW5S5bmRXmhaQgeOyFujOzyrp5nvl77lSqKSgKdnY+MHla84iEwJt 08lsjf6ZAIX/gVm7V45A1+XADaZ5/UMpY5ZWeNuwbJgMvC2X+1MSk8t7nJYqemxJFNR+ xFDAQjYXjkutC9xQaFdT1OInZTstNE7JAgBqqokrT47U16H0fKNxJNdb3jfNh+ypOqhN ZQtw== X-Gm-Message-State: AOAM531UnVcuKggIId3TtkHZMV3+KWNScHmUcVMeXrAzgt1PdE9FNlI8 ++TETSWN3kCJtnd0B4Y0RHb/U/EiQLOBrmn+vjjQZXnv X-Google-Smtp-Source: ABdhPJxskc2g2PJS68HQvZtTAmuoDEc8+qrsvg41tyBuzOVKdSxTeWUdNkd2PCAb7eU8HQ0/mfknwIrp/K3aGmTC4RA= X-Received: by 2002:a05:6602:14c8:: with SMTP id b8mr263322iow.209.1621332972547; Tue, 18 May 2021 03:16:12 -0700 (PDT) MIME-Version: 1.0 References: <6do5xN2g5LPnFeM55iJ-4C4MyXOu_KeXxy68Xt4dJQMhi3LJ8ZrLICmEUlh8JGfDmsDG12m1JDAh0e0huwK_MlyKpdfn22ru3zsm7lYLfBo=@protonmail.com> <30li5MRxkBhzLxLmzRnHkCdn8n3Feqegi-FLZ5VDyIX2uRJfq4kVtrsLxw6dUtsM1atYV25IfIfDaQp4s2Dn2vc8LvYkhbAsn0v_Fwjerpw=@protonmail.com> In-Reply-To: <30li5MRxkBhzLxLmzRnHkCdn8n3Feqegi-FLZ5VDyIX2uRJfq4kVtrsLxw6dUtsM1atYV25IfIfDaQp4s2Dn2vc8LvYkhbAsn0v_Fwjerpw=@protonmail.com> From: Zac Greenwood Date: Tue, 18 May 2021 12:16:01 +0200 Message-ID: To: Bitcoin Protocol Discussion , ZmnSCPxj Content-Type: multipart/alternative; boundary="000000000000e4334f05c297ffbe" X-Mailman-Approved-At: Tue, 18 May 2021 10:25:18 +0000 Cc: SatoshiSingh Subject: Re: [bitcoin-dev] Opinion on proof of stake in future X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 May 2021 10:16:14 -0000 --000000000000e4334f05c297ffbe Content-Type: text/plain; charset="UTF-8" VDFs might enable more constant block times, for instance by having a two-step PoW: 1. Use a VDF that takes say 9 minutes to resolve (VDF being subject to difficulty adjustments similar to the as-is). As per the property of VDFs, miners are able show proof of work. 2. Use current PoW mechanism with lower difficulty so finding a block takes 1 minute on average, again subject to as-is difficulty adjustments. As a result, variation in block times will be greatly reduced. Zac On Tue, 18 May 2021 at 09:07, ZmnSCPxj via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > Good morning Erik, > > > Verifiable Delay Functions involve active participation of a single > > verifier. Without this a VDF decays into a proof-of-work (multiple > > verifiers === parallelism). > > > > The verifier, in this case is "the bitcoin network" taken as a whole. > > I think it is reasonable to consider that some difficult-to-game > > property of the last N blocks (like the hash of the last 100 > > block-id's or whatever), could be the verification input. > > > > The VDF gets calculated by every eligible proof-of-burn miner, and > > then this is used to prevent a timing issue. > > > > Seems reasonable to me, but I haven't looked too far into the > > requirements of VDF's > > > > nice summary for anyone who is interested: > > https://medium.com/@djrtwo/vdfs-are-not-proof-of-work-91ba3bec2bf4 > > > > While VDF's almost always lead to a "cpu-speed monopoly", this would > > only be helpful for block latency in a proof-of-burn chain. Block > > height would be calculated by eligible-miner-burned-coins, so the > > monopoly could be easily avoided. > > Interesting link. > > However, I would like to point out that the *real* reason that PoW > consumes lots of power is ***NOT***: > > * Proof-of-work is parallelizable, so it allows miners consume more energy > (by buying more grinders) in order to get more blocks than their > competitors. > > The *real* reason is: > > * Proof-of-work allows miners to consume more energy in order to get more > blocks than their competitors. > > VDFs attempt to sidestep that by removing parallelism. > However, there are ways to increase *sequential* speed, such as: > > * Overclocking. > * This shortens lifetime, so you can spend more energy (on building new > miners) in order to get more blocks than your competitors. > * Lower temperatures. > * This requires refrigeration/cooling, so you can spend more energy (on > the refrigeration process) in order to get more blocks than your > competitors. > > I am certain people with gaming rigs can point out more ways to improve > sequential speed, as necessary to get more frames per second. > > Given the above, I think VDFs will still fail at their intended task. > Speed, yo. > > Thus, VDFs do not serve as a sufficient deterrent away from > ever-increasing energy consumption --- it just moves the energy consumption > increase away from the obvious (parallelism) to the > obscure-if-you-have-no-gamer-buds. > > You humans just need to get up to Kardashev 1.0, stat. > > Regards, > ZmnSCPxj > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev > --000000000000e4334f05c297ffbe Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
VDFs might enable more constant block times, for instance= by having a two-step PoW:

1. Use a VDF that takes say 9 minutes to resolve (VDF being subject to d= ifficulty adjustments similar to the as-is). As per the property of VDFs, m= iners are able show proof of work.

2. Use current PoW mechanism with lower difficulty so finding a = block takes 1 minute on average, again subject to as-is difficulty adjustme= nts.

As a result, variat= ion in block times will be greatly reduced.

Zac


On Tue, 18 May 2021= at 09:07, ZmnSCPxj via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:<= br>
Good morning Erik,

> Verifiable Delay Functions involve active participation of a single > verifier. Without this a VDF decays into a proof-of-work (multiple
> verifiers =3D=3D=3D parallelism).
>
> The verifier, in this case is "the bitcoin network" taken as= a whole.
> I think it is reasonable to consider that some difficult-to-game
> property of the last N blocks (like the hash of the last 100
> block-id's or whatever), could be the verification input.
>
> The VDF gets calculated by every eligible proof-of-burn miner, and
> then this is used to prevent a timing issue.
>
> Seems reasonable to me, but I haven't looked too far into the
> requirements of VDF's
>
> nice summary for anyone who is interested:
> https://medium.com/@djrtwo/vd= fs-are-not-proof-of-work-91ba3bec2bf4
>
> While VDF's almost always lead to a "cpu-speed monopoly"= , this would
> only be helpful for block latency in a proof-of-burn chain. Block
> height would be calculated by eligible-miner-burned-coins, so the
> monopoly could be easily avoided.

Interesting link.

However, I would like to point out that the *real* reason that PoW consumes= lots of power is ***NOT***:

* Proof-of-work is parallelizable, so it allows miners consume more energy = (by buying more grinders) in order to get more blocks than their competitor= s.

The *real* reason is:

* Proof-of-work allows miners to consume more energy in order to get more b= locks than their competitors.

VDFs attempt to sidestep that by removing parallelism.
However, there are ways to increase *sequential* speed, such as:

* Overclocking.
=C2=A0 * This shortens lifetime, so you can spend more energy (on building = new miners) in order to get more blocks than your competitors.
* Lower temperatures.
=C2=A0 * This requires refrigeration/cooling, so you can spend more energy = (on the refrigeration process) in order to get more blocks than your compet= itors.

I am certain people with gaming rigs can point out more ways to improve seq= uential speed, as necessary to get more frames per second.

Given the above, I think VDFs will still fail at their intended task.
Speed, yo.

Thus, VDFs do not serve as a sufficient deterrent away from ever-increasing= energy consumption --- it just moves the energy consumption increase away = from the obvious (parallelism) to the obscure-if-you-have-no-gamer-buds.
You humans just need to get up to Kardashev 1.0, stat.

Regards,
ZmnSCPxj
_______________________________________________
bitcoin-dev mailing list
= bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mail= man/listinfo/bitcoin-dev
--000000000000e4334f05c297ffbe--