[Applause]
that's all right
hi everyone I'm Vincent Jameson I work
for the etherium foundation doing some
DevOps core developer liaison work
actually let's go I guess do intros real
quick and then I'll get started on kind
of an overview frog pound that will jump
into some of the other stuff around it
so that's my intro hi I'm Melina and I
work as a programmer on the guillotine
and I'm also the security lead for a
foundation in regards to this very mean
poster I had no authority
I just Ina Garten all centralized
authority all right so how many of you
in here are familiar with Prague pal is
that almost almost I've okay you got at
least one person so I want to explain a
bit so on your some other paper coming
in so Prague Pal is stands for
programmatic proof of work and basically
in the etherium white paper it was
mentioned that aetherium was designed to
be Nasik resistant basically a special
a specialized hardware chip that's meant
to I guess in the cryptocurrency world -
specific cryptocurrency algorithm so as
supposed to be a resistance so there's
this thing called T hash or at Nash
people call it different things and it
is the proof-of-work algorithm that is
used in aetherium so what a 6 came
online
risa there in the last year I guess year
and a half starting to get worried some
people because they are was because
Asics were originally not supposed to be
on the network and there was some
concerns from other cryptocurrency
communities like Banaras the cash that
Asics would join the network in a way
that was not as altruistic as GPU mining
pools or would attack the network or for
the secret you know mining groups and
the factor that it would push GPU miners
out of the ecosystems GPU miners were
pretty so that's kind of what pow-pow
came from a group called infidels
it was semi-anonymous created pronto the
if and if death else was a crystal
applying hand who's been the spokes
person for prague town for this time the
other developers have not been revealed
since then there's been a lot of
politics and some technical
on Proc Palin general including some
conspiracy theories some fun you know
listen that back it's worth on Twitter a
lot of research has been done on proc
pow because of this I believe it was
first made it like March of 2018 that
your purse start being developed and
we're here now and I guess it's November
twenty hi to October and we're still
talking about it so it's very I would
say there's a contentious topic within
the etherion community back when the
core developers were deciding whether or
not to implement product pal once it was
at a point of being decided for
implementation the core developers made
the decision to implement it into a
future hard fork but because there was
all this noise around the development be
a product how itself the back of January
the etherium cat herders were assigned
to have some audits done or basically to
organize audits around product au and we
selected at least Authority for the
primarily software part of the ha audit
and Bob brow as the person doing need
more Hardware piece of the audit and
those were completed months ago and yeah
at least authority I used to talk about
there and
the deal and Martin has been helping
with the get the pigmentation of it and
also started a test net which he could
talk about a little bit I think it's
called Gangnam right just net for Prague
how to make sure that it is viable for
the network so we'll get into some
discussion kind of around a little bit
of the technicals a little bit of the
politics and kind of like reach out to
you all to see who is ask questions and
where you want these topics to go so on
Thrones at least Authority and then they
can throw it to Martin and then we can
go from there so you know we were
selected basically to do this audit and
we know that sometimes that what we knew
we were aware this is a pretty
contentious topic but we do see arable
as auditors to just look and report on
what we see so I'm aware we can't really
offer too much in terms of what the
community can do and how it should
handle and everything but it was more
about just reflecting on what we found
with prop pal so we looked at it for I
think a little bit over a month I think
is about five weeks and then we produced
her word
got populist choice and of August or in
September but it's public now so that
report is out there for people to read
some of the feedback that we've gotten
report is that people understand it but
kind of don't understand it that is just
because it's really it's really we had
to get into really technical stuff when
doing the security on it it's really
just like dig deep and try to figure out
what exactly what's going on and you
know we report things on a high level
and then we also give suggestions of
what should be potentially improved
about prog Powell but I mean basically
that we found that it achieves its goal
of making a six basic we need to be like
GPS and order to in order to work with
it and so that really disadvantaged any
kind of basic production to a basic
advantage when they were produced so we
also looked at what like the so knowing
that we also wanted to really analyze
what would happen
the teacher in particular ways how that
would be so impractical felt also that
kind of extend the life of the audit
information that we provide to the
community so because you know there's
only so much you can write about like
hey this is just how it works I so we
wanted to really look at that so we
tried to capture some things in the
report - that said if this specific
hardware advancement happens in the
future then this is the potential issue
that might result in them more
specifically that was around the light
evaluation mining and then we also had
some a dissertation or catch a function
- and those two items seem to be the
ones that are you know most up for
discussion areas besides that we also
did some other suggestions that are the
word it's about the documentation and
some of that - yeah
so you all can read the report for more
details we're also here to talk today if
there's any specific questions about
that
[Music]
oh really I can just mention that test
them so there was a test that started a
long time ago I can't accept to remember
when it was it was based on in Paris
apparently a ton on implementation which
was later merged into the pair decline
so it can be activated by a genesis for
gif
it was never merged into the client so
they kept lines that participated
intestine were basically based of guess
a PR which by now is kind of staled as
far as I know the Tesla is still
operating and - running it they are also
running it on dedicated GPU - and I
don't know at this point how many folks
it has transitioned through but it's
quite a lot and as far as I know there's
no problems with it
great
so yeah that's how I understood it as
well so diving into the politics a
little bit the latest on that I guess or
actually maybe even a background so
there has been some back-and-forth
there's a kind of a hair that's all out
there
Christine might han is a very
sort of magnetic figure like a
controversial figure and the space
because of her past affiliations and the
way she's kind of handled communications
and the back-and-forth that they've had
with these and manufacturers which I
should mention these if manufacturers at
times have also been you know a little
bit like us rowdy with their
communication as far as being anti prog
pal obviously because they're basic
manufacturers they weren't going to want
it so I don't really want to go in there
like super detail about that but there's
a lot of interesting articles and back
and forth some Twitter conversations we
dive into to get more information on
that and I think that there are two
sides to this obviously the technical
and the political and the technical has
been fleshed out using the audits and
technical discussion and then the
political side has not been fleshed out
because there's a lot of very strong
opinions from certain people because
there's so many signs of the day it's
even a debate as to whether the
community is loud about it or whether
it's just a few very vocal minority
groups that are just really loud about
it in general so it's really hard to
parse that it goes out of that and as
someone who's kind of community manager
in the space this has been one of the
hardest things to reason with is getting
the signals from the community about
whether or not Prague palace wanted
or things like that we know the GP
minors positions we know some
individuals in the community their
positions we for the most part of the
core developers position you know the
ones who have spoken out for prog pal a
lot of it is kind of abstaining from an
opinion as well which is a choice and is
something that is important in being
able to make that choice of that
decision when you are deciding something
so I think it is a really important
discussion I think that front love you
might want to do this for the panel we
might want to just like have technical
questions from the audience or something
and discussion and then people want to
throw in some politic discussion later
which will probably have it because more
people are more familiar with that side
of it I think then that would be cool
too so if anyone has questions on or the
specifics that Liz mentioned or any
technical questions feel free and add
just if you don't mind come up to the
microphone so it can be on the recording
or whatever you not to show your face
I'll just hit the microphone
suddeniy one have any questions yet Jeff
already attitude whatever so I know we
can read the report from this is already
but I think like one of the technical
questions that I've seen coming up a
couple times is this notion of like if
if the creators of our cars these
shadowy figures like what there's some
secret basic ability you know I hear and
I wonder if you could just kind of like
summarize lately like basically the
rough conclusion of the report on this
idea of like is it possible that that
the developers that would have a secret
ASIC up their sleeves and on a higher
level not that we can find
I mean security audits aren't a perfect
two thing we look if we spend a certain
amount of time and we look as hard as we
can also Bob spent months also
who was looking at the hardware and he
really liked I mean our team was
communicating with him too and we really
dug into some things and that's how we
came up with even the weight evaluation
from that one supply chain attack
manufacturing side attacks if we can do
certain things but experiment this
project is concerned it cannot really
affect anything
[Music]
effect anything more than that
[Music]
that is like currently we have cash from
the cash so cash is a star like 30 and
we just argued and disclosed and
technicality damn this is much bigger
like 4gb start with 1gb of something
attempted crows or dime now what if you
can
evaluate the tag on the fly so currently
the bag is pre and later before a period
and then for the next period you pre
calculate the tag and switch to it so
that you don't suffer any delay since
it's the new video so now what if you
can calculate the tag on the fly from
the cache so for that you need to store
these and dev cash or check
so right now the or cheapness Ram is
very expensive or harder so it's very
expensive I am right now you see the
current cpus and gpus are a few
kilobytes there is also the power memory
much higher than the power to access the
internal memory so there is a big
advantage when things are in the
internal ram so now according to Bob who
is an expert in hardware after few years
maybe four or five years down the line
maybe 20 23 24 we may see higher and
higher capacity
as our cheapest trap or it will become
cost-effective to put SRAM more and more
as our disappeared or the die so that is
probably point these attacks are the
more practical so there are ways to
mitigate that you can equal to increase
the number of patterns that are going
into the bag so the computation part of
it dominates the memory part of it
because if you're also doing some
computation right to do FMV the values
together and attach them so you could
increase the number that are fetching
blocks from the cache that's one way to
mitigate that and also the size of the
cache and the tyrosine so that would
also be working against this hardware
advances because on one side Hardware is
advancing that it will become more and
more feasible to put memory more and
more memory to the die whereas it should
increase the cache size for example say
next iteration we are going to have say
200 MB it's a time they become more
difficult to put that cost will work and
yes you did I
it's great at this
okay do they have other technical
questions
so when you say that there's a light
mining attack or convenience like my bio
is repeated like an overview or was that
was that pretty much sustained okay yeah
that'd be perfect
I guess basically what that means right
now is that it's not possible right now
that we think it could be possible in
five four to five years but there is a
mitigation strategy that can be
implemented now and it also affects -
not just brought about the key - to pull
anyone else yeah sure
I mean this might be too broad but like
[Music]
so Rob how is a variation of you - it
wasn't it's implemented in Java it's
been a few months of some of this may be
a bit rusty remember from my memory but
so first you need to get some seed
values in your mixers from this dag and
that's where the main memory access
comes from and then a low goes up and
you start asking 32 lanes in each one of
those lanes there's like some 16 or 32
things that you do of math these
parameters change all the time so I'm
sure anything that goes wrong but with
some of the numbers to do some math and
to do that math you also take in each
lane stuff from various parts of the dag
all over the place to do that math and
you do this some number of times you
know there's more
and there are math executions right now
so you do this and each lane is entirely
independent there's like supposed to be
32 lanes I think you're 16
so each independent ake its math from
its mix take take some stuff from the
deck do some math together and then send
it to another lane and you knew this
about 30 or 40 times you get that mixed
date together so it's designed so that
the computation is very recognizable
especially in context of a GPU
architecture and it saturates the whole
GPU by using all of the functions of GPU
might have except for floating point
because floating point is kind of
emerging across all the vendors integers
is you know if you can't an integer math
you should get out of computer science
it's pretty simple
pulling points is where things get weird
so they love that out of the spec
because it's not certain enough so you
take all that stuff you catch it
together at the end and take that final
hash take your on a file to check hash
against it and then that's what you
that's the results of your of the hash
that you get and then you do the regular
old mining stuff where you check it
against the difficulty see if it's
successful enough if not it hits it back
and if you're a miner out there you have
a less difficult than the cult's you do
to prove that you tried and failed so
there's you know the regular old mining
techniques that go on from that but
that's a high-level overview of kind of
what happens I have code
so that's also how its implemented in go
theremin parity when you implement this
for a chip you there's also this
internal period on the books I think you
need a way to get you know and then okay
okay for later for the for the next spec
of work pot and yet one of the reasons
there the gift program hasn't emerges
that we're not sure if we should march
the oh nine one or mine next anyway so
the thing is on if you run from GPU what
to do is that every 50 blocks you
recompile the GPU program and you
reprogram the GPU for the next 50 blocks
and that's the kind of programmatic part
and this sheet that you use can do but
which makes it harder to implement this
as a that's a specific server circuit
amazing totally I mean please get the
program apart so many many reasons but
one of the interesting things that one
of the implementations found is the
actually found a bug in a GPU compiler
when they were running the program and
had a very simple fix by the thing about
these programs as they are the it's not
really random and pseudo-random and the
seed is the block number of the period
that's going on with it so you can
totally run all your combinations up to
you know 10 million 20 million blocks to
make sure that your CPU can handle it so
you know there's some can there were
some concerned initially that this might
break you know the CPU things are at our
risk and any responsible minor what you
know be running these programs out and
they are tuned advanced to see it stuff
blows up or you know
they just have you just need to have one
rig to test to make sure that your stuff
works awesome answers alright any other
questions
[Music]
I just wonder are all the is all the
controversy non-technical are there any
technical controversies and then I was
curious about your description of the
tests that it seemed to me you would you
want to have a very rigorous test matter
in such a realistic to understand first
it's our second question first
so in general we'll need to set up the
test and tried a new hard work what we
want is a very lively test then so that
we can like for example for crops done
and then we can execute transaction and
see that the execution of transaction
still happens the way they would the way
they showed them that the variable
sensors for profile that's hopefully not
needed at all the only thing that we
wanted to verify is the envelope of the
blocks the proof of work and the
verification and the mining of this work
so we totally don't care anything at all
about the content of the gloves so as
long as it's what we wanted to do was to
get maximum coverage of transitions
because we realized that they are one
one of the interesting points where
things could break is an epoch
transitions because that's when attack
changes and if I recall correctly there
was there is some minor tweak to improve
power which made it interesting to just
see that we would be able to manage
moving across epochs and this whole
thing about the clock period of 5050
works so that the main concern about the
test nut is to have it running over long
sequence of blocks and have GPU - mine
them and then it doesn't really matter
how many clients are
and not even matters which kinds are
only tested as long as at some point
when we take apart implementation we
check that yeah I can import block zero
to two million and it's very priced
correctly it doesn't need to do it in
real time as the books come along I'll
take some of the technical controversy
questions that's what I was fairly new
to a core development when paka was
really getting its main push so I was
drawn to that and I want to make sure
that you know that there are any
technical concerns of those that iron
out too quick I'm one of the first poems
that had is the spec was initially
written was it really clean room
implementable it was depending upon code
blocks and test vectors that weren't
very well SPECT out test wise so I went
and I implemented in Java I had to use
Powell's implementation to get some test
vectors out of it severe point know Java
has got some of its own issues it
doesn't have unsigned integers which you
know is where most of my bugs came from
but from those I was able to create some
some unit tests and some data tests for
transition to prove that you can get the
particular blocks in it there's so many
different functions there's there's a
test vector now for each of the
functions and that's what was needed so
I tighten up some of that and the bit I
mentioned about the concern about
compiler bugs was another technical
controversy but that is you know
basically how good are miners at their
DevOps I mean this is their business
the only thing is there's another thing
that they might need to pay attention to
but you know the good ones will know
what's going on with it and you know
these as long as your communication to
each other like you know like a lot of
them are it's just you know it's another
thing you got to worry about that's it's
totally within their own area of what
they can handle so I think that covers
most the technical content
were you aware of any others I think
someone said that nvidia gpus were
faster than a MDGs and I think there was
benchmarking done to prove that wrong
remember it's like tweak or there was
yeah there's something like that I think
that's where the o9 3 spec came from can
I drop some of the numbers to make sure
and to say that the AMD's and the Nvidia
is are stronger it's really you want it
as for a particularly ambi modelers like
Nvidia one is much lower than the other
so the question is you know is that the
Nvidia's are better detach or that
Andy's worse and you know do we make it
so it's you got the same sort of that
adjustment and it's it's a lot more
within ballpark now between those two -
there's no architectural design
decisions done that particularly favor
Nvidia or AMD not that I know anything
about how to do their architectures the
big changes were to take a lot of stuff
down at 32 bits and all GPUs nowadays or
32-bit GPS so if there was a 32-bit
version of a particular algorithm that
Sloan was preferred and that's why they
went to could check at 800 is because
it's 32-bit based and you put that
through a GPU through the 32-bit
integers those things are like optimized
to know and in just blazes right through
so that was part of the decisions of why
they did a lot of their changes was to
make it optimized for the general class
of GPUs not one over the other and
another technical I wouldn't say
controversy per se but maybe questions
still to be solved is if going from E -
as moto to propound there is still the
difficulty so there a theorem uses a
difficulty formula which is totally
dependent on the previous book and if
the perfectly proper hashing engine is
half as fast that means that it will
take quite a bit longer
find an elaborately difficult block so
there will be very slow blocks unless
maybe a housing or a modification to the
difficult to formula difficult
calculation at the point where switch is
made so that's still something that can
be elaborated with ensure that progress
is nicely some take a picture of all of
us before Martinez delete reading and
then to be difficult happens sit down
thanks everyone
okay and yeah you got to make you next
time over there longside o memory the
Pokemon bubbly okay perfect
all right any more technical otherwise
we'll jump in the political I'll be fun
there are some things you mention of the
block jump if we did nothing and take
about three or four hours to cut in half
there's also a slight impact on the ice
age and that impact there is if it only
felt like two weeks to a month earlier
because of the exponential nature of the
ice age I think it was the third thing
played it might have gone in but it's
not too critical it's arrogance no
worries the one happened when they when
they thought the transaction rated at
the beginning again it's you know we
communicated another time I'll be fine
or we went go ahead and do a difficulty
cut combine that with a nice
you know I think it'll be fine
do you talk a little bit about the fvg
resistance of Prague now and it's
cost-effective actually try to run
around FPGA I think the talked about
three and the period the 50 blocks the
random max period we need to recompile
the program and kept a few blocks that
block video is like too small to really
be compiled PGA pro - and furthermore
the power requirements in FPGA is a lot
more that much harder looking at that so
the a little bit today
there exists FPGA accelerators that you
can plug into the GPU to offload can
change political track for bread yeah so
to offer the cat's-eye calculation from
the GPU to an FPGA and it so that works
really well for a test that's I think
two portions of catch a king so that so
using one of these accelerators on it -
tend to does it to make it more
effective and on the pro pal it's not
harder to get that kind of boost from
fpga accelerator because the portion of
power that is spent on that operation is
a lot less
okay so we have about 10 minutes left
little by little less than that maybe
seven so let's go into politics I guess
something for the politics of it does
anyone have any questions or comments I
really can't real question you know what
is it it's product that the last mining
algorithm they beat one point ax wasn't
the last algorithm so I've heard that
they have a little like knobs in it you
can might adjust to like make it harder
yeah I don't understand it but you know
for now that's a question for for the
answers of that is we would even know
the answer when 82.0 is happening and
even then we need to know all the
details which we're getting really close
to having Melanie tell us about how each
one point though is going to interface
with either 2.0 and I believe the latest
answer is it's going to be in an
execution environment or an EE which
will then I guess be decided if it will
go indefinite
for a while stills I understand it might
phase out naturally or there might be a
push to do everything from 1.0 2.0 where
it'll be inside chard I've heard many
different things as they what happening
yeah so my answer to that would be most
likely but it's really nice if we keep
the freedom to say that hey we don't
promise I think we might swap out praça
we're from out with something really
silly and that is trivial to implement
and in a sec or we might do something
totally different you never know just
and realistically yeah I don't think I
don't think I mean if you switch proper
now I don't think it will be simple to
do another switch later obvious I
thought proper would be kind of
controversial and pretty is the thing
and most people would be like yeah
whatever
so anybody else anything else okay other
questions
yeah I just I didn't know if you know
it's gonna turn me is a it's a four core
contentious forward so I mean is there
any evidence and I apologize I've read
the report that eighty six bubble was a
systemic risk to the system where there
is something wrong that that poses to
seventh graders is just a really appease
the GPU miners and if this is you know a
short term I think before we would
approve a stake is all of this really
needed to have one potential contentious
for my personal opinions been developing
over time on this and personally and
this is not necessarily a community
perspective but one of the most
interesting I guess ideas behind this is
the fact that right now the GP mining
pulls the major ones we know them as
then you can go to a chart of that one
either scan or any of the other blog
explorers and you can see it Sean pie
chart it says like either mine and F to
pool and spark pool and so we know them
we know that spark pulls helped out in
the community we know that F two pool
has helped out a little bit and we know
that ether mines help out a lot with the
technical stuff so I guess either might
would be more technical help smart pool
would be both technical and community
help with their initiatives to do stuff
in the ecosystem when I was a co-working
spaces in China and conferences
educational sessions so we know they're
all good actors the thing with that I
always think back to this myth an era
when suddenly there was a lot of hash
rate that dropped off after the fork
that we hadn't no idea who they were and
they didn't know there was a Benares and
it wasn't public so someone built an
ease that they started mining on there
and so they could basically do whatever
they wanted to anonymously so as we know
all the actors now if smart people tried
to do a double spend or they tried to I
used to think there might be a way that
like they could mess up that's you point
out a transition that is less likely now
after talking to Danny Ryan but there
are some things that an anonymous large
percentage of hash power could do like
double spending right before because
they know that their investments about
to drop off completely GPU miners can
switch to other algorithms Asics they're
stuck on ET cash nor they're stuck on
product pal so it's more the only major
what implemented prog pala then what do
you what do they have to lose if you're
anonymous and just want to do a double
spend on an exchange because our
conformation times are much lower so
that's the best argument I've heard so
far in favor of prog pound so that's
kind of where I met as far as a good
arguments ago
and the fact that I knew shoot down the
idea that we made a deal with GPU miners
or that because of the issuance
reduction that there was this
implication that we would
doing wrong pal because I know at the
time there was some people saying that
but I did a huge block reddit post that
kind of dispelled that and included
timestamps - core developer calls and
things like that where we discussed not
doing that so as far as this is there
going to be a fork or not there's no way
to know and it's going to depend on I
guess my main opinion on a personal
level is that there won't be because to
have a successful court you need a
dedicated team of developers who can at
least code one client and there would be
people maybe from PTC or other ports of
aetherium that can pick that up but I
don't see any of them speaking up right
now maybe if it gets closer so most
become and they'll say yeah we're ready
to take on a work of this and we're
married we're against this so much it's
the principles of it that we're going to
do it but I just haven't seen that yet
so it's hard for me to believe people
underestimated that with e.t.c we had
never had that before again so I'm not
saying it's impossible at all it's
definitely possible but I don't know the
percentage right now a possibility no I
mean if that did happen I'd see that
arising organically in that same point
of e.t.c find a way yet is that there's
a lot of people who can fork a repo can
run continuous integration can tweak
parameters may not have the ability to
move them you know improve things for
much beyond that that they can at least
keep the network going they can do a
simple and then hope together you know
that I'll be behind that that's how I'd
see yeah you know that contention
happening they could happen it on the
other direction
there was actually code there was
actually a developer who was on the
discourse back in january/february who
was about to do a prog how four can head
code ready and Bates picked I don't know
why he backed off they would be
persuaded him the Bronco wasn't dead but
he was very committed to make it happen
so he actually had code in place and
people in place and connections to
actually or he was really good at
bluffing it's hard to tell but that an
actual work the other thing that
happened is that there was another
proposal which was sort of like okay
let's maybe do one so we're not going to
fool what sanitarium but what we're
basically going to start from scratch
we'll make a new Genesis yeah yeah
that's like finding places another
possibility so our time is up
unfortunately I'll be in the hallway to
talk we work and Martin asked right so
yeah tell me on Twitter if we took a pic
I'd love to see my face everywhere right
so yeah thank you all for coming so much
[Applause]
you