►
Description
A workshop held on November 14, 2022 about blockchain interoperability. This is a three hour online course to introduce the core concepts and principles of blockchain interoperability. You will learn the foundations of interoperability, followed by an introduction to several Hyperledger projects on the field: Weaver, YUI, Firefly, and Cacti. We present in depth several Cacti's components, including its Plugin Architecture, API Server, Test Development & Execution (All-In-One Container Images), an Hello World of Cacti, and considerations about the future of the project.
For more about Hyperledger Cacti, visit: https://wiki.hyperledger.org/display/cactus/Hyperledger+Cacti@UCy-AB5ehLFqh1FtCVIH4Q3A
For more about Hyperledger Firefly, visit: https://wiki.hyperledger.org/display/FIR/Hyperledger+FireFly+Home
For more about Weaver, visit: https://github.com/hyperledger-labs/weaver-dlt-interoperability
For more about Yui, visit: https://github.com/hyperledger-labs?q=yui&type=all&language=&sort=
And we encourage you to ask questions on the #cacti-contributors channel on Hyperledger's Discord server: https://discord.com/channels/905194001349627914/908379338716631050
For more about Hyperledger's Discord server, check out https://chat.hyperledger.org/
----
Hyperledger – Open Source Blockchain Technologies
Hyperledger is an open source community focused on developing a suite of stable frameworks, tools and libraries for enterprise-grade blockchain deployments.
It serves as a neutral home for various distributed ledger frameworks including Hyperledger Besu, Fabric, Sawtooth, Indy, as well as tools like Hyperledger Avalon, Cactus and libraries like Hyperledger Aries, Ursa. Learn more about Hyperledger projects: https://www.hyperledger.org/use
Discord: https://discord.gg/rVCn4j7UFd
Case Studies: https://www.hyperledger.org/learn/case-studies
Training & Certification: https://www.hyperledger.org/learn/training
Tutorials: https://www.hyperledger.org/use/tutorials
Webinars: https://www.hyperledger.org/learn/webinars
Events: https://www.hyperledger.org/events
Vendor Directory: https://www.hyperledger.org/use/vendor-directory
Subscribe to the Hyperledger Newsletter: https://www.hyperledger.org/newsletter
Follow-us on Twitter @Hyperledger
Learn about Hyperledger Membership: https://www.hyperledger.org/about/join
#Hyperledger #Blockchain
License
Creative Commons Attribution license (reuse allowed)
A
All
right,
everyone
thank
you
for
joining
us
for
the
hyperledger
cacti
blockchain
interoperability
with
hyperledger
cacti
Workshop
we'd
like
to
thank
Raphael
and
Peter
for
being
the
workshop
leaders
for
this
session
in
the
chat.
If
you
have
any
questions
or
comments,
you
can
leave
them
there.
We
will
have
folks
checking
it.
A
We
also
have
a
Discord
at
hyperledger,
which
I'm
going
to
put
the
link
to
once
again
I'll
put
in
there
every
10
or
15
minutes
in
case
somebody
shows
up
late
where
the
cacti
Community
is
there
they're
discussing
the
project.
They
are
working
on
things
together,
it's
a
great
place
for
folks
to
gather
and
to
ask
questions
as
well.
We
are
also
live
streaming.
This
on
YouTube
and
I'm
gonna.
A
Put
that
link
into
chat
as
well
in
case
anyone
has
a
colleague
who
might
want
to
see
this
at
a
later
date.
You
can
share
that
with
them.
It
will
be
in
the
hyperledger
foundation,
YouTube
channel
right
now
on
stream,
but
also
later
on,
as
a
recording
that
anybody
can
check
out
and
with
that,
I
would
like
to
turn
it
over
to
Rafael
and
Peter.
B
Thanks
a
lot
Sean
hi
everyone,
I'm,
fafel
I,
will
be
presenting
this
Workshop
that
we've
been
organizing
in
the
last
couple
months
focused
on
high
project
cacti
for
your
information.
We
started
doing
the
workshop
where,
when
the
project
was
hypoallergenic
cactus
after
that
there
was
a
merge
between
Cactus
and
a
project
called
Weaver,
and
hence
the
name
cacti.
So
we're
going
to
talk
a
bit
about
the
cactus
specific
components,
but
also
touching
a
bit
on
Weaver.
So
you
have
a
complete
picture
so
we'll
be.
B
So
just
a
quick
note
about
block
demon
block
demon
provides
nodes
and
staking
services.
So
if
you
have
any
cryptocurrencies,
you
could
do
delegation
to
our
nodes,
but
the
interesting
thing
about
about
demon
is
that
they
provide.
We
provide
a
multi-chain
API
called
ubiquity,
similarly
to
Cactus,
but
it's
more
aims
towards
public
blockchains,
various
factor,
it's
more
aimed
towards
private
blockchain,
so
we
brought
ubiquity
into
cacti.
B
B
So
the
the
alpha
news
is
follows:
first,
we're
going
to
focus
on,
let's
say,
first
of
all
on
the
setup
because
hyperological
cacti
takes
a
while
to
configure
and
to
build
and
to
be
able
to
for
us
to
to
see
things
working.
So
we're
going
to
tackle
that
first
and
after
that,
we're
going
to
talk
about
the
formalization
systematization
of
interoperability
and
also
hyperledger
I
have
to
send
to
our
partners
from
UE
Firefly
and
also
from
the
Weaver
folks.
B
That
now
are
are
brothers
in
arms,
with
cacti
for
being
able
to
and
for
demonstrating
availability
to
talk
about
your
projects
that
are
related
to
interoperability
and
related
to
our
own
project.
So,
thank
you
very
much,
and
then
we
have
a
break
10
minutes
break
on
the
second
part,
we're
going
to
talk
about
the
different
components
of
hyperledger
cacti,
so
it
will
be
a
bit
shorter
and
finally,
we're
going
to
have
a
Hands-On
session.
Where
we
talk
about
the
possible
example
applications.
B
We
have
currently
available
a
more
complex,
in-depth
application
that
will
be
presented
by
Peter
the
supply
chain
app
and
also
an
application
made
by
Andrea
busto,
who
was
doing
a
summer.
Internship
implemented
the
cbdc
interoperable
applied
from
using
hypoallergic
cacti.
So
that
will
be
very
interesting.
B
B
First
of
all,
the
quick
setup
we
can
use
a
Dev
container,
which
is
a
functionality
from
Visual
Studio
that
allows
you
to
build
the
environment
in
a
Docker
container,
okay.
So
this
this
should
be
more
or
less
straightforward.
If
you
have
a
Linux
machine
and
the
instructions
are
there,
so
you
can
go
to
hypology
cacti
project
GitHub
project,
and
then
you
go
to
the
dot
Dev
container,
and
then
you
have
the
instructions
there
you
can
follow
up.
B
You'll
have
you'll
have
enough
time
to
build
the
project.
Be
aware
that
you
need
to
make
sure
that
your
machine
has
enough
time
and
storage
since
hyper
larger
character
uses
a
lot
of
talker
images.
The
storage
grows
very
quickly
and
if
your
machine
gets
runs
out
of
storage
of
it
will
be
very
difficult
to
you'll.
Have
strange
everything
don't
be
possible
for
you
to
use
cacti,
but
the
the
manual
setup.
You
need
to
install
the
prerequisites.
So
we
we
tested
this
for
Ubuntu
20.
We
need
git,
you
need
node,
npm,
Docker,
etc,
etc,
etc.
B
B
B
B
D
E
E
No
problem
all
right,
just
a
very
quick
intro
to
your
hype.
Ledger.
This
is
not
going
to
be
the
best
possible
introduction,
because
that
one
is
always
done
by
Daniel
antart,
but
I'll
try
my
best.
Basically,
the
hyperledger
foundation
is
a
collection
of
Open
Source
projects
aimed
at
distributed,
Ledger,
Technologies
and
things
tooling.
E
So
it's
not
just
a
single
one.
There's
actually
plenty,
there's
also
different
tiers.
So
you
can
see
a
list
of
the
projects
here.
Some
of
them
are
graduated
projects,
which
is
the
stage
that
you
can
reach
by
being
an
incubation.
First
cacti
is
an
incubation.
We
hopefully
get
the
the
graduated
stage
later
this
year,
or
maybe
early
next
year,
depending
on
how
fast
things
move.
E
We
do
try
to
have
a
very,
very
welcoming
and
inclusive
community,
so
you
can
always
feel
free
to
drop
by
and
see
what
kind
of
contributions
you
could
make
or
which
projects
artifacts.
You
could
use
for
something
that
you
want
to
build
yourself
and
there's
also
mentorships,
which
are
a
great
way
to
get
some
real
world
experience
with
mentors
who
will
actually
help
you
I'm
one
of
those
mentors
so
I
think
the
next
iteration
starts
next
summer.
D
B
B
So
there
are
different
models
for
blockchain
interoperability
and
tons
of
great
research,
great
systematizations,
and
there
are
different
ways
to
look
at
the
things.
But
the
way
we
found
to
be
suitable
and,
at
the
same
time
comprehensive,
is
to
classify
the
solutions
into
interoperation
modes
and
then
each
solution
we
can
conduct
such
that
we
can
conduct
an
assessment
to
each
solution.
So
there
are
three
interoperation
modes:
data
transfers,
asset
transfers
and
asset
exchanges.
Interoperation
modes
basically
tell
you:
what
is
the
thing
that
we
want
to?
That
is
the
object
of
interoperation
right.
B
What
what
is
the
object?
That
cacti
will
manipulate
manage
in
between
different
ledgers,
let's
say,
and
then
we
have
the
interoperation
assessment.
If
we
want
to
measure
how
powerful
interoperability
Solutions
are
with
regard
to
each
other,
we
can
classify
them
with
the
p
levels
and
with
the
C
levels.
So
the
the
P
levels
tell
if
the
system
interoperates
with
other
systems
as
it
is
so
the
higher
the
P
level,
the
better
the
interoperation
capabilities
of
the
system,
while
the
sea
levels
have
evaluated
the
interoperation
capabilities
of
a
set
of
systems.
So
how?
B
How
well
can
a
pair
of
systems
interoperate
and
we'll
talk
a
bit
more
in
detail
about
it?
So
data
transfers
are
very
simple.
You
have
piece
of
data
on
the
source
blockchain.
You
want
to
send
it
to
Target
blockchain
via
an
IM
interoperability
mechanism.
You
basically
replicate
that
data
and
push
it
onto
the
target
watch.
These
data
transfers
are
relatively
easy
to
do,
especially
because
we
don't
have
any
restrictions
on
these
operations.
For
example,
you
don't
need
to
assure
that
there
is
no
double
spend
of
information,
contrary
to
asset
transfers
in
asset
transfers.
B
You
have
an
asset
on
a
soft
blockchain
and
you
want
to
move
it
to
a
Target
blockchain.
The
way
to
do
this
is
to
lock
the
asset
on
the
source
blockchain
and
to
create
a
representation
of
that
asset
on
the
target
blockchain
so
effectively.
You
are
not
transferring
assets
across
blockchains
because
you
can't
really
do
that,
but
what
you
can
do
is
lock
in
one
side
and
unlock
in
the
other,
and
then
the
objective
of
your
interoperability
mechanism
is
to
synchronize
both
ledgers,
such
that
it
is
always
locked
in
one
side.
B
B
B
So,
for
example,
if
you
have
a
system
providing
P1
level
interoperability,
it
means
that
you
can
have
different
functionalities
on
the
same
cell
network
that
belong
to
the
same
DLT
Network
that
belong
to
the
same
DLT
protocol,
communicating
and
exchanging
data
and
working
with
each
other's
data,
so,
for
example,
interoperability
across
smart
contracts.
Right
if
we
step
on,
for
example,
level
P3,
we
have
interoperation
across
same
functionality,
same
sub,
Network,
same
DLT,
Network,
sorry,
same
functionality,
same
sub,
Network,
same
DLT
network,
but
across
on
the
same
DLT
protocol.
B
B
On
the
other
hand,
we
have
the
sea
levels.
So
the
sea
levels
Define
how
well
a
pair
of
systems
work
together
and
we
basically
have
three
and
the
intuition
is
the
higher
the
more
standardized
and
the
more
matured
those
ecosystems
are.
So
if
you
have
level
C1,
it
means
that
you
can
communicate
in
the
semantic
layer,
meaning
you
can
execute
one
protocol,
for
example
an
asset
transfer.
B
Okay,
and
after
this,
what
we
do
with
this
information.
Well,
we
can
draw
a
table
where
we
have
our
different
P
level,
C
levels
and
the
interoperation
modes,
and
we
have
a
group
of
references.
Imagine
that
we
want
a
system
that
supports
B4
C1
and
is
NSA
transfers.
We
go
on
to
these
columns
and
then
we
basically
try
to
match
which
one
stick
in
all
our
requirements:
okay
and
then
we
can
see
that
for
those
sites,
basically,
those
numbers
are
citations.
B
B
B
Right
some
some
more
references
for
these
formalization
and
standardization.
We
have
a
talk
on
this
at
hypological
forum
and
there's
also
two
papers.
You
wrote
about
this
so
feel
free
to
check
them
out
all
right
now.
I
would
like
to
call
Rama
to
present
the
Weaver
specific
parts
from
cacti.
Are
you?
Are
you
there
Rama
yep.
B
A
B
A
F
Okay,
can
I
move
that?
Can
we
move
to
the
next
slide?
Please
yeah.
So
Rafal
already
talked
about
the
use
case
pattern.
So
just
for
just
to
give
you
some
history,
we
started
the
Weaver
project
and
about
three
and
a
half
years
ago,
and
it
was
not
named
Beaver
until
about
a
year
and
a
half
ago
when
we
open
sourced
it
to
hyperledger
Labs.
F
So
we
started
off
with
by
trying
to
figure
out
a
taxonomy
of
use
case
patterns,
and
this
is
what
he
came
up
with
and
we
call
it
data
sharing
what
Rafal
talked
about
the
data
transfer.
We
used
to
call
it
data
transfer,
but
we
we
just
using
the
term
sharing,
because
people
had
some
confusion
with
the
terminology
but
yeah.
It's
the
the
same.
The
use
case
patterns
that
rafale
was
talking
about
earlier.
F
Moving
to
the
next
slide,
please
so
the
Weaver
framework,
the
way
we
wanted
to
we
were
we
envisioned
building
it.
The
kind
of
design
choices
we
wanted
to
make
was
around
was
ensuring
that
different
networks
would
remain
independent,
self-sovereign
maintain
their
own
privacy
and
would
not
require
any
kind
of
third
party
to
mediate
between
them
for
interoperative
purposes.
F
So
the
mechanism
or
their
plans
we
use
for
that
purpose
was
the
envisioned
networks
possessing
one
or
more
relays,
and,
as
you
can
see
here,
you
have
a
relay
representing
three
networks
in
the
picture,
so
to
run
any
kind
of
cross
into
protocol,
be
it
for
data
sharing
or
for
exceeding
assets
or
for
transferring
an
asset
from
one
network
to
the
other.
The
Envision
rate
is
happening
through
these
relays.
F
So
what
you
can
see
here
is
the
vision
that
we
can
enable
using
the
using
these
protocols
and
with
cacti
you
get
this
network
of
network
Vision,
where
you
can
different
networks
remain
they
function.
According
to
the
native
logic,
they
run
the
same
business
workflows
as
they
were
designed
for
all
they
have
to
do
is
they
have
to
run
an
extra
relay
component
using
which
they
can
communicate
with
other
networks,
to
share
data
exchange,
assets
and
transfer
assets,
and
so
on
and
by
the
way.
F
F
The
sort
of
Internet
acquiring
you
can
run
these
kinds
of
protocols
using
either
cactus
cactus
kind
of
node
server,
or
we
will
kind
of
relay
which
actually
the
Gateway
as
an
English
neatest
point
for
every
Network
so
and
the
relay
is
the
component.
We
expect
to
also
allow
networks
to
communicate
with
a
traditional
Enterprise
systems
of
record,
that
is,
centralized
systems,
networks
which
have
record,
which
have
databases
that
are
not
actually
shared
across
multiple
views.
Next
is
yeah.
This
is
I'm
not
going
to
go
into
the
details.
F
This
is
just
a
blow
up
of
the
relay.
The
relay
has
a
DLT
neutral
part
which
you
see
on
the
left
and
a
particular
drivers
or
plugins.
You
can
see
on
the
right,
which
are
specific,
which
are
used
to
drive
specific
logic
into
a
particular
ledger,
so
the
DLT
neutral
part
is
going
to
be
running
a
protocol
with
other
relays
in
a
way
that
is
completely
agnostic
of
what
the
network
behind
it
looks
like.
So
you
have,
you
can
imagine
DLT
protocol
a
the
t80
protocol
C
through
the
relays.
F
F
Next
slide,
please
so
the
the
the
animation
networks
or
and
the
interoperability
systems,
having
particular
basic
capabilities
or
building
blocks,
using
which
we
can
engineer
the
kinds
of
protocols
that
Raphael
and
I
talked
earlier
detail
sharing
the
asset
exchange
asset
transfers.
So
the
capabilities
of
the
relay.
There
are
certain
core
capabilities,
and
then
there
are
certain
convenience
capabilities
like
syntactic
sugar.
We
can
add
over
so
in
order
to
enable
ease
for
ease
of
use
for
developers.
So
the
core
capabilities
are
for
the
relays.
F
Please
now,
on
the
networks
themselves,
there
are
particular
core
capabilities
that
they
will
have
to
perform
in
order
for
this
transaction
to
this
cross
Network
operation
to
remain
decentralized
and
the
they
will
be
performing
them
using
the
logic
of
smart
contracts.
So
these
are
capabilities
which
we
will
be
deploying
in
the
form
of
smart
contracts
in
fabric.
You
can
imagine
them
as
chain
code
encoda.
They
will
be
running
as
a
sort
of
a
Cod
app
that
that
is
going
to
be
deployed
in
all
the
nodes
and
a
set
of
capabilities.
F
They
need
to
do
our
tiny,
Access,
Control
checks
on
any
request
coming
from
outside
the
network,
generating
the
proof
for
a
given
Ledger,
State,
validating
the
state
proof
pledging
or
locking
an
asset
and
the
ability
to
claim
or
take
them
an
asset.
So
these
operations
are
core
capabilities
that
have
been
performed
on
the
contracts,
because
that's
the
only
way
we
can
ensure
that
the
a
network-wide
decision
on
these
on
on
these
operations
next
slide.
Please
yeah.
F
Our
claim
is
that
this
is
a
complete
set
of
building
blocks
that
can
realize
any
sort
of
constantive
dependency.
Again,
it's
a
claim.
We
don't
have
a
theoretical
proof
for
this,
but
something
we'll
be
analyzing
as
you
go
back,
go
on
next
slide,
so
the
data
sharing
is
we're
going
to
be
relying
on
the
basic
building
blocks
of
generation
and
proof.
Verification
and
asset
transfer
is
the
way
we
implemented.
This
is
by
relying
on
multiple
instances
of
a
data
sharing
protocol.
F
Now
there
are
other
ways
of
doing
asset
transfer
as
well,
and
maybe
I-
don't
know
if
you'll
come
to
this
today,
but
there
is
a
standardization
effort
going
on
under
the
ages
of
the
ipf,
where
we're
trying
to
standardize
an
asset
transfer
protocol
that
can
ensure
that
an
asset
leave
one
network
and
goes
to
another
in
an
atomic
manner.
So
that's
something
that
we
will
also
be
incorporating
into
cacti
asset
exchange.
F
Finally,
it's
multiple
asset
logs
and
claims
and
and
possible
unlocks
if
the
transistor
doesn't
go
through
and
it
follows
the
logic
of
hdlc
or
the
hash
download
contract
next
slide.
Please
not
going
to
go
into
these
details,
but
this
was
the
viewer
architecture
and
we
are
trying
to
now
merge
it
with
the
cactus
architecture
in
order
to
produce
a
emerged
data
architecture.
It's
just
that.
The
main
components
here
are
I
already
talked
about
the
relays
and
associated
with
the
protocol.
Drivers.
F
Interoperation
module
is
just
the
kind
of
very
Bland
name
we've
given
to
the
set
of
contracts
that
are
supposed
to
be
deployed
on
the
network.
In
addition,
application
helpers
on
the
bottom
left,
you
see
our
the
the
SDK
and
the
API
that
you
provide
to
an
application
developer
or
the
business
logic
that
is
supposed
to
be
driving
any
sort
of
cross
network
data,
query
or
asset
exchange
operations
and
there's
also
an
identity
service.
F
Don't
have
to
have
to
go
into
this,
but
the
we
have
mechanisms
in
Weaver
and
we
have
written
a
couple
of
research
paper
on
this
topic
whereby
we
can
use
the
the
did
concept
or
the
decent
price
identity
concept
to
allow
two
different
networks
to
communicate
and
sync
their
CA,
the
authority
certificates
so
that
they
can
then
validate
signatures
on
the
proof
that
they
get
from
the
from
some
party
in
another
Network.
Next
slide,
please.
F
So
this
is
typically
how
a
hyperledger
fabric
Network
would
be
adapted
with
Vivo
components
and
yeah
again
going
forward.
There
will
be
cacti
components,
so
you
can
see
a
typical
subject:
Network
on
the
top
left.
It
has
peers,
ordered
and
Cas.
Then
it
has
a
smart
contracts
with
chain
code
and,
above
that
it
has
the
the
layer
2
applications,
the
the
ones
built
on
the
fabric.
F
Sdk
now
what
you
need
for
in
order
for
that
Network
to
review
or
enable
this,
you
have
to
add
one
or
more
relays
that
act
as
gateways
and
associate
with
the
relay.
You
have
to
have
certain
drivers
which
are
going
to
be
engineered
the
same
way
as
you'd
build
any
fabric
application
and
your
the
actual
fabric,
applications
that
are
interested
in
interoperation.
They
will
be
augmented
or
they
will
import
the
Weaver
SDK
and
the
helper
functions
in
order
to
drive
any
sort
of
cost
into
transactions
and
the
middle
layer.
F
You
see
the
fabric
interoperation
chain
code,
that's
the
Weaver
chain
code,
the
the
beaver,
smart
contracts
containing
all
of
the
basic
building
blocks
like
the
proof,
presentation,
verification,
Logic,
the
lock,
locking
an
asset
taming,
an
asset.
Those
are
implemented
in
one
chain
code
that
you're
supposed
to
be
installing
on
and
deploying
all
the
peers.
Next
slide.
Please,
we
have
something
very
similar
for
Corda.
Do
not
go
into
this
in
detail,
but
I.
Think.
F
If
you
are
familiar
with
how
korda
Works
very
similar
to
your
peers,
then
you
have
card
apps
in
two
different
in
or
three
different
layers.
You
have
the
contracts
and,
on
top
of
that
flows,
on
top
of
that,
you
can
have
the
client
of
the
UI
layer
and
if
you
look
at
the
bottom
right,
the
Weaver
components
are
very
similar
to
what
you
saw
in
fabric.
F
You
have
relays,
you
have
drivers,
you
have
instead
of
the
interoperation
chain
code,
you
have
in
preparation
card
app
and
then
above
that
in
the
client
application
it
can
excise.
The
the
Weaver
called
SDK
yeah
a
few
questions
there.
Okay,
let
me
I'll
address
the
question
when
I
finish
next
slide,
please,
okay,
I!
Don't
have
to
go
into
this
in
detail.
F
Yeah
I
think
you
can
keep
going
I
think
I'll
probably
skip
this,
because
we
are
out
of
time
right
so
yeah.
If
you
want
to
again.
This
is
something
we're
going
to
be
putting
to
cacti
very
soon,
but
right
now,
if
you
are
eager
to
try
this
out,
there
is
ample
documentation.
We
have
a
full
tutorial
that
we
can,
where
you
can
run
sample
test
networks
which
are
provided
within
the
legal
code
base
and
Sample
applications
that
you
can
install
and
then
run
in
probability.
F
Protocols
next
slide
yeah,
and
if
you
want
more
information
this
you
always
go
to
the
rfcs
folder
and
a
bunch
of
papers
and
articles
listed
in
the
overview
page
next,
please,
okay,
so
how
to
merge
viewer
with
cactus.
So
this
is
something
that
both
the
the
cactus
maintenance
and
the
Weaver
maintenance
have
been
discussing
and
working
on
for
better
part
of
a
year
and
be
the
goals
for
this
joint
interoperability
number.
F
So
there's
a
lot
of
similarities
in
both
goals
and
philosophy
between
the
two
projects,
Cactus
and
Weaver,
and
but
the
two
projects
also
offers
something
some
distinct
and
unique
features.
So
the
way
we
wanted
to
merge
them
was
we
would
be
fusing
together
the
components
that
are
being
roughly
the
same
serving
roughly
the
same
purpose
and
then
you're
going
to
be
aggregating
and
offering
his
choice.
The
other
kind
of
components
so
yep
that,
in
a
nutshell,
should
cover
what
our
vision
for
merging
is
next
slide.
A
F
A
separate
relay
for
each
DLT
protocol.
What
you
have
to
create
is
the
protocol
adapter
or
the
protocol
driver
for
each
dat
protocol,
so
that
I
mentioned
in
an
earlier
slide
that
I
really
had
two
parts,
a
DLT,
neutral
part
and
the
DRT
specific
part.
The
DAT
neutral
part
is
something
you
you
can
just
take
as
a
universal
Appliance
and
you
can
you
just
have
to
configure
it
for
your
particular
network.
Are
there
any
evolving
standards?
Yes,
so
the
VR-
and
this
is
something
that
Rafael
is,
has
also
been
keenly
involved.
F
F
The
philosophy
is
a
network
is
represented
by
a
Gateway
and
that
if
the
network
wants
to
send
an
asset
over
to
another
Network
or
communicate
some
kind
of
data
other
network,
it
is
going
to
rely
on
its
gateway
to
do
that
by
talking
to
the
Gateway
of
the
other
network.
That's
very
similar
to
what
I
showed
you
for
for
viewer
with
the
with
the
two
reviews,
so
that
is
standard
which
we
are
still
working
on
a
lot
of
people
from
different.
F
A
F
Relay
is
not
a
smart
contract,
the
really
is
the
messaging
the
device.
What
is
that
is
a
separate
smart
contract.
That's
running
on
the
network
which
the
relay
through
its
protocol
driver,
is
going
to
hit
so
think
of
this.
As
you
have
two
networks
and
then
in
the
middle,
you
have
two
relays,
so
the
relays
act
as
the
communication
components,
but
a
lot
of
the
core
functionalities
actually
happen
in
the
networks
and
because
the
networks
are
not
centralized
modules.
F
The
the
logic
for
running
any
sort
of
anything
on
those
end
networks
involves
running
them
in
the
native
contact
logic,
so
in
fabric
you'll
be
running
it
as
a
chain
code
quarter,
you'll
be
running
it
as
a
card
app,
so
so
yeah.
The
relay
is
just
a
machine
component
but
backing
it
in
the
network
is
smart
contract.
So
and
yes,
you
can
create
one
for
it.
Even.
F
Is
I
think
there's
nothing,
the
theoretically
or
technically,
that's
stopping
it.
We
just
haven't
yet
built
a
POC
for
that,
but
we
hope
to
in
the
near
future.
So
right
now
we
have
relays
and
cross
network
data
sharing
and
asset
exchange
for
fabric
and
quarter
networks
and
to
some
extent
for
bezel.
But
we
are
going
to
work
on
extending
support
for
public
ethereum,
maybe
Cosmos
and
so
on.
B
B
C
Please
allow
me
to
introduce
yui
a
hyperledger
law
project
which
focuses
on
the
interoperability
for
heterogeneous
blockchain
networks.
In
a
nutshell,
for
me,
UE
puts
more
emphasis
on
the
communication
layer
compared
to
tactile
for
achieving
its
trustless
general
purpose.
Question
communication,
whereas
cocktails
as
a
whole
cocktail
as
a
whole,
puts
more
emphasis
on
the
integration
of
the
whole
system
with
blockchains,
but
it
seems
it
has
a
much
similarity
in
the
architecture
to
Weevil.
So
there
is
a
relay
module
in
UE,
which
corresponds
to
the
relays
in
Weaver.
C
So,
first
and
foremost,
UE
is
based
on
IBC,
inter
blockchain
communication
protocol
from
the
Cosmos
X
system.
Cosmos
is
a
public
blockchain
project
which
aims
to
build
the
internet
of
blockchain
within
the
ecosystem
they
compiled
sets
of
standards
for
blockchain
communication
as
the
foundation
for
cross-chain
communication.
C
C
Mainly
supports
hyperledger
public
base
holder
and
we
are
working
on
supporting
public
aquarium
and
program
in
the
family
and
yeah
Cosmos
supports
the
the
IBC
itself.
So
someone
asked
me
a
question:
can
you
connect
hyperledger
public
to
Cosmos
Hub?
Yes,
with
high
voltage,
love
UE,
you
can
do
that
through
the
IDC
portable.
C
In
this
slide,
I
summarize
the
typical
categorization
to
achieve
interoperability
among
blockchain.
The
difficulty
of
intellectual
communication
is
that
how
one
can
guarantee
a
certain
transaction
in
Pioneer
finalized
in
the
first
chain
which
ignized
the
following
procedure
in
the
destination
chain,
so
the
straightforward
way
is
to
let
the
trusted
start.
Party
play
the
role.
This
will
be
also
called
the
external
validator
patterns.
C
C
C
So
they
see
the
high
level
overview
of
IBC
architecture
with
the
within
the
IBC
module,
which
facilitates
communication.
There
are
several
other
selections
similar
to
tcpip,
such
as
pocket
connection,
Channel
and
Cloud.
A
client
is
a
central
entity
for
chain
verification
and
the
video
handle
the
physical
transport
of
packets.
C
More
specifically,
pocket
has
payload
and
true
the
proof
structure
and
the
specification
is
lecture
dependent.
Basically,
proof
is
used
for
the
attestation
that
the
certain
payload
is
actually
finalized
in
the
source
chain.
Poor
body
data
set
and
the
macro
loot-based
chain
like
ethereum.
This
will
be
confirmed
by
check
header,
which
verifies
the
block.
Header
is
signed
by
validator
set
and
verify.
Membership
which
verifies
a
certain
key
value
pair,
is
included
in
the
world
State
through
macopath
verification.
C
So
if
we
want
to
facilitate
complex
transactions
such
as
delivery
versus
payment,
we
need
more
foundation
on
top
of
reliable
communication
I'm
not
going
into
full
details
of
this
middleware,
but
basically
what
it
does
is
to
provide
functionality
of
a
locking,
store
and
transaction
qualitative
coordination.
Like
two-phase
commit
by
this
functionality.
You
can
coordinate
transaction
in
the
destination
chain
if
a
certain
transaction
in
the
source
chain
success
and
vice
versa,
foreign.
C
We
are
currently
working
on
LCP,
light
client
proxy,
which
you
can
consider
it
as
an
extension
to
UE.
So
it
facilitates
a
trusted,
execution,
environment
or
t
technology
for
verification.
Basically,
we
substitute
the
computational
computation
on
the
security
enhanced
hardware
for
part
of
on-chain
verification,
but
this
will
enable
efficient
verification
of
counter
about
blockchain.
Yet
yet
does
not
sacrifice
the
good
security
property
of
IDC.
C
B
Thank
you
very
much
to
zoom.
Does
anyone
have
any
questions
or
the
meantime?
Let
me
comment
that
you
is
a
very
interesting
solution,
because
it
one
of
the
reasons
is
that
it
uses
IBC,
which
is
one
of
the
de
facto
standards
for
interoperability
in
the
public
blockchain
world
and
effectively
the
proofs
that
you
carry
on
those
IBC
packets
are
verified
on
chain
making
it
the
trust,
assumption
being
the
security
of
the
source
chain
right.
B
B
That's
correct
for
some
technical
details
chain.
You
can
search
for
Merkel
proofs
or
in
the
case
of
ethereum
Marco
Patricia
tree
roofs,
that
basically,
you
can
assert
that
a
certain
event
or
a
certain
transaction
were
incorporated
into
an
evm-based
blockchain
on
a
counterparty
blockchain
on
chain.
That
is
why
the
security
of
such
protocols
is
so
so
nice.
It
doesn't
depend
on
a
centralized
set
of
parties,
a
certain
the
messages
valid.
D
G
G
So
Firefly
is
what
we
describe
as
a
super
node.
It's
a
complete
stack
for
Enterprises
to
build
and
scale
secure
web
3
applications.
So
what
does
this
mean?
Well,
it's
it's!
It's
not
a
DLT!
It
sits
a
layer
above
the
blockchain
and
it
is
a
platform
that
makes
it
easy
to
build,
build
blockchain
applications
on
so
it
provides
an
API.
G
It
provides
web
sockets
and
a
really
familiar
user
experience
to
software
developers
that
are
used
to
building
traditional
web
2
apps
makes
building
web
3
apps
a
familiar,
look
and
feel
and
experience
for
them.
So
when
we
look
at
all
the
things
you
need
to
build,
a
web
3
app
I'm
going
to
go
through
this
really
quickly.
Hopefully
you
know
the
audience
here
is
familiar
with
what
it
takes
to
build
a
blockchain
app,
but
you
know
down
at
the
bottom.
G
You
have
your
your
chain
so
say,
for
example,
I
want
to
build
an
app
that
can
mint
some
tokens
and
trade
transfer
tokens
on
a
public
chain
or
something
like
that.
I
need
a
blockchain,
node
I'm,
going
to
keep
some
data
off
chain
as
well.
There
are
great
open
source
projects
for
both
of
these
things
already
so
I'm,
probably
not
going
to
reinvent
these
things.
G
Yeah
I
might
be
using
an
ethereum,
node
or
Fabric
or
Basu,
or
you
know,
there's
a
lot
of
different
things.
I
can
hear.
I
can
use
here,
so
I
will
also
need
a
token
smart
contract,
some
code
to
submit
transactions
index
events
I'll
need
some
code
to
talk
to
my
my
off
chain.
Data
store,
I
need
to
manage
all
My,
Signing,
Keys,
wallet,
balances
and
I
need
some
code.
G
G
Private
I
don't
want
to
put
all
of
my
users
information
on
the
chain
that
sort
of
thing
I'm
going
to
need
to
write
the
actual
business
logic
of
my
application
and
my
backend
API
and
finally,
my
front
end,
my
web
UI
or
mobile
app,
or
something
like
that
so
in
in
the
previous
world
before
Firefly.
This
would
be
all
code
that
I
would
have
to
worry
about
writing
and
so
Firefly
changes.
This
picture
and
it
takes
the
entire
middle
chunk
of
this
and
says:
well,
let's,
let's
have
an
open
source
platform
that
we
can
reuse.
G
That
can
be
extended.
It's
pluggable
that
can
work
with
many
different
blockchains
that
can
work
with
many
different
types
of
data
stores
and
and
have
that
be
open
source,
and
that
would
be
a
common
Foundation
that
lots
of
different
projects
can
build
their
applications
on
top
of,
and
then
that
lets
me
as
the
the
application
developer
focus
on
just
these
top
two
boxes
of.
G
What's
my
business
logic,
and
what's
my
user
experience
like
now,
maybe
I
have
a
custom
Smart
contract
already
and
I
I
still
really
care
about
the
very
particulars
of
the
smart
contract
or
what
chain
it's
running
on
Firefly
lets.
You
do
all
these
things.
I
can
still
come
down
here
to
this
layer
and
I
can
customize
all
these
things.
I
can
use
my
own
contract.
G
G
Firefly
allows
you
to
build
apps
flows
and
digital
assets,
so
it
has.
It
acts
as
a
an
API.
Gateway
has
a
great
wonderfully
documented
HTTP
API,
both
restful
and
RPC,
where
appropriate
it
can
generate
on
the
fly.
It
can
generate
a
HTTP
API
with
full
Swagger
documentation
from
a
custom.
Smart
contract
has
a
lot
of
really
awesome
features
for
for
for
smart
contracts
and
interacting
with
blockchains.
G
It
allows
you
to
build
complex
flows
of
data.
Both
that's
you
know.
Part
of
it
is
on
chain,
but
also
private
data
needs
to
be
kept
off
chain
to
to
share
data
within
a
multi-party
network
or
to
keep
certain
data
private,
and
it
has
a
great
API.
It's
just
really
easy
to
use
user
experience
for
managing
digital
assets
like
tokens,
both
non-fungible
and
fungible
tokens.
There's
a
great
user
interface
that
we'll
look
at
in
just
a
minute
for
seeing
token
balances,
transfers
managing
wallets
that
sort
of
stuff.
G
So
I'm
going
through
this
really
fast,
but
there's
there's
just
a
a
ton
of
stuff
in
Firefly
that
makes
it
really
easy
to
build.
Applications
on
top
of
blockchain
Firefly
can
operate
in
two
different
modes,
so
one
of
them
is
called
Gateway
mode,
and
this
is
you
know:
I
have
a
firefly
node
and
there
is
a
blockchain
somewhere
that
I
want
to
connect
to,
and
maybe
it's
a
public
chain.
Maybe
it's
a
private
chain
I
just
want
to
connect
to
it
and
I
want
to.
You
know,
perform
transactions
on
that
chain.
G
G
Sorry
about
that,
so
how
does?
How
does
all
this
fit
together
with
cacti
and
and
Firefly
so
cacti
and
Weaver,
as
we've
seen,
are,
are
focused
on
change
chain?
Sync
and
there's
some
some
awesome
stuff
going
on
there.
So
I
can
sync
state
or
value
or
or
data
from
one
chain
to
another.
Firefly
can
also
talk
to
multiple
different
blockchains.
Its
focus
is
on
application
to
blockchain
sync,
so
my
application
can
use.
Firefly
Firefly
can
talk
to
multiple
chains.
G
It
can
submit
transactions
on
both
chains,
it
can
index
events
on
both
chains
and
it
allows
my
application
at
an
application
layer
to
work
across
different
chains.
So
hopefully
this
is
a
just
a
a
short
and
sweet
picture
of
kind
of
how
they're
different
how
they're
trying
to
accomplish
different
things,
with
a
few
minutes
that
we
have
left
here,
I
would
love
to
just
show
a
really
quick
example
of
sort
of
this.
G
This
picture
of
firefly
talking
to
two
different
chains,
so
on
my
machine
over
here
I
have
this
is
a
one
Firefly
note
that's
running
and
it's
been
configured
with
two
different
namespaces.
It's
been
configured
to
talk
to
a
a
fabric
Network,
so
this
is
my
Consortium,
my
private
Consortium
Network
and
there's
one
other
organization
within
that
Network
as
well,
and
that
browser
is
running
over
here.
I've
color
coded
this
one
green.
G
G
So
this
the
the
sandbox
is,
is
not
necessarily
like
a
Production
Tool,
but
it's
more
of
a
way
to
be
introduced
to
Firefly,
so
Firefly
I
I
don't
have
time
to
run
you
through
all
the
features,
but
it
has
so
great
messaging
capabilities
built
in
so
right
now,
I'm
in
my
in
my
private
fabric,
Consortium
Network,
so
I
can
I
can
share
data
with
other
members
of
my
Consortium.
I
can
share
it
privately
or
I
could
share
it
publicly.
G
So
if
I
send,
this
is
a
broadcast
to
everyone,
I
can
run
that
and
that
will
send
a
public
message
to
everyone
else
in
the
fabric.
Network
I
could
also
send
a
private
message
and
I
could
attach
a
file
to
this.
I
could
browse
for
a
file
or
I
could
send
a
Json,
payload
or
I
could
just
send
a
string
and
I
could
choose
which
recipients
I
want
to
receive
it.
I
actually
only
have,
because
this
is
connected
to
the
fabric
samples
test
Network.
G
There
are
only
two
orgs
in
the
network,
so
there's
only
one
one
other
option
here
to
send
to,
but
so
I
could
send
this
as
a
private
message
and
if
I
hop
back
over
to
my
Explorer
I
can
see.
There's
there's
been
some
new
activity
here,
let's
go
over
to
the
other
window
and
we'll
refresh
this
one
and
we
should
be
able
to
see
yeah.
Some
some
messages
came
in
here.
Here's
my
private
message
that
I
just
received
there's
lots
of
information
here.
G
I
can
I
can
go
to
the
actual
message
and
click.
This
one
I
could
see
that
the
signing
key
that
it
was
sent.
So
this
was
sent
from
org
one.
This
I'm
look
currently
looking
at
orc
2's
node
right
now
you
can
see
this
is
the
private
one
and
just
for
completion.
We'll
look
at
this
was
the
oops
here's
the
broadcast
to
everyone.
G
Okay,
so
that's
pretty
cool,
but
that's
just
you
know
my
private
Network.
My
node
is
also
configured
to
talk
to
a
public
chain
as
well,
so
I
can
I
can
switch
namespaces
over
to
the
Mumbai
test.
Network
and
I
can
go
down
to
my
tokens
dashboard
here.
I
can
see
that
I
have
one
token
pool
configured.
It
has
a
hundred
FFC
in
it
and
I.
It's
currently
I've
just
minted
it
to
my
node's
address
but
say
I
wanted
to
transfer
some
of
that.
G
Well,
Firefly
also
has
a
really
awesome,
Swagger
UI
that
allows
you
to
use
any
of
its
apis
just
built
in
here.
So
there's
a
lot
of
endpoints
I'm
going
to
scroll
down
to
the
transfer
endpoint
here
now,
I'm
just
going
to
do
a
quick
token
transfer,
so
I'm
going
to
do
this
in
the
Mumbai
name,
space
I'm
going
to
transfer
we'll
transfer
10
and
this
token
contract
has
18
decimals.
So.
D
G
I
I'm
not
going
to
attach
a
message
to
this
transfer.
I
could
there's
there's
a
lot
of
really
rich
metadata
capabilities
with
firefly
I
can
attach
a
message.
I
can
attach
data
to
the
transfer
as
well.
Just
some
some
really
awesome
features
there
again.
I
don't
have
time
to
go
into
all
of
them
today,
but
I'm
going
to
transfer
this
to
my
metamask
address
so
I
have.
G
This
is
a
completely
different
wallet
here
connected
to
the
same
public
chain,
I'm
just
going
to
copy
this
address
here
and
I'm,
going
to
put
it
in
the
to
address
here
and
that
looks
good
hit,
execute
and
okay,
so
I
got
a
I
got
an
ID
for
that
that
transfer
operation
it
will
take,
because
this
is
a
public
chain
and
that
needs
to
be
mined
into
a
block.
It
will
take.
G
Is
configured
in
my
metamask
wallet,
so
I
met
a
mask
on
on
test
networks.
Doesn't
always
it
won't
pick
up
new
token
contracts
automatically
so
I'm
just
going
to
paste
the
token
address
in
there
and
I
import
it
and
look
at
that.
It
already
sees
that
I
have
10
FFC,
so
Firefly
made
that
super
easy
to
to
do
transaction
both
on
on
my
private
Consortium
and
on
this
public
chain
and
super
easy.
If
I
go
back
here,
I
should
be
able
to
refresh
and
there
now
we
can
see.
This
is
new.
G
This
transfer
with
data
transaction
that
I
just
did
here.
That's
now
on
the
public
block
Explorer
as
well
so
tons
of
cool
stuff,
you
could
do
I
wish
I
had
more
time
to
go
into
more
features,
but
there's
plenty
of
great
material
out
on
on
the
YouTube
channel
on
the
hyperledger
YouTube
channel
on
Firefly
and
lots
of
lots
of
great
recordings
out
there.
If
you
are
interested
in
learning
more
about
Firefly,
please
get
involved.
We
are.
We
have
a
channel
on
Discord
as
well.
We'd
love
to
chat
with
you.
G
There
Firefly
is
open
source
like
all
these
other
hyperledger
projects.
The
source
can
be
found
in
the
hyperledger
GitHub
org
and
yeah.
Thanks
for
for
this
time
today,
to
present
to
this
group
and
talk
about
blockchain
interop
and
it's
my
my
pleasure
and
that's
that's
all
I
have
for
today,
I
don't
know
if
I
have
time
for
questions,
but
that's
all
I've
got
thanks.
B
G
Yeah
so
I'm
also
just
scanning
through
chat
here,
I
see
your
message
there
as
well,
so
multi-party
mode
is
typically
used
in
a
private
permissioned
blockchain.
So
there
is
some.
There
is
some
level
of
trust
between
the
members
of
the
chain
there.
So
a
new
member
of
the
Consortium
would
be
onboarded,
and
other
members
of
the
Consortium
would
be
aware
that,
okay,
this
this
new
company
is
joining
our
Consortium.
That's
great.
The
first
time
a
firefly
node
joins
a
multi-party
network.
G
There's
a
process
that
it
can
go
through
to
register
itself
on
the
network
and
it
it
will
basically
advertise
its
its
identity.
It
will
claim
an
identity
on
the
blockchain
using
its
signing
key
and
then
from
that
point
forward.
All
of
the
other
nodes
will
be
aware
of
that
node's
identity
and
be
able
to
verify
that
future
messages
are
indeed
from
that
node.
B
G
Absolutely
in
fact,
that's
exactly
what
we
just
saw:
I
apologize
if
we
were
running
through
it
too
quickly,
but
the
first
two
transactions
that
I
did
the
the
message
broadcast
on
the
private
message.
The
those
were
both
happening
on
my
fabric,
test,
Network
private
chain
that
was
running
on
my
machine,
so
I
use
I
cloned
the
fabric,
samples,
repo
I,
started
up
test
Network
and
I
connected
Firefly
to
it,
and
I
ran
those
transactions
on
that
private
chain.
That
was
running
on
my
machine.
G
The
the
token
mint
and
the
token
transfer
that
you
saw
me
do
I
did
that
transfer
live
that
was
happening
on
a
public
chain.
You
could
you
could
actually
go
look
at
polygon,
scan
on
your
own
machine
and
see
those
transfers
that
I
just
did
in
real
time
there
so
yeah,
absolutely
both
both
public
chains,
private
chains.
At
the
same
time,
Firefly
can
do
both.
E
E
Ultimately,
what
we
want
to
aim
is
to
solve,
as
the
DLT
fragmentation
there's
a
lot
of
distributed
letters
out
there
and
there
will
likely
be
more
in
the
future
as
well.
So,
if
you're
an
organization,
then
you
want
to
start
using
it.
You
want
to
buy
into
one
of
them.
You
want
to
have
maybe
a
little
bit
of
a
safety
net
to
try
and
figure
out
what
happens
if
that
particular
Ledger
gets
discontinued,
or
you
realize
later
on
that
some
characteristics
of
it
are
not
a
good
fit
for
use
case
Etc.
E
That's
why
I
just
want
to
see
I
have
a
shout
out
for
him.
Thank
you,
Rafael
and
then
yeah.
That's
the
stats
back
on
the
fragmentation
problem.
I
just
like
to
expand
on
this,
because
the
common
sense,
like
intuitive
requirement
from
everybody,
if
he
has
done,
would
be
that
all
of
these
different
letters,
all
these
different
pieces.
E
Software
should
just
be
able
to
talk
to
each
other,
no
problem,
but
then
that's
just
not
the
case,
even
though
intuitively
as
humans,
we
would
want
it
to
be,
and
the
hard
part
of
it
is
that
the
number
of
letters
you
have
you
need
a
quadratically
growing
number
of
Integrations.
If
you
truly
want
each
ledger
to
be
able
to
communicate
with
every
other
letter
in
the
set
of
letters
that
you
have.
E
E
E
If
you
have
a
white
paper,
the
section
of
that
that
I
recommend
the
most
is
the
example
use
cases,
because
those
are
kind
of
Timeless
in
the
sense
that,
as
the
architecture
have
changed,
some
of
the
diagrams
or
sections
are
have
become
a
little
bit
outdated
in
the
white
paper.
But
the
example
use
cases
are
kind
of
forever.
E
If
you
have
a
Discord
server.
Just
to
reiterate
that
you're
very
welcome
to
join
there
and
ask
questions,
and
the
most
important
thing
is
that
we
do
have
daily
pair
programming
calls
every
weekday
and
if
you
want
to
join
in
there,
you
can
there's
no
any
kind
of
requirements
to
qualify
and
it
is
a
short
call.
It's
just
15
minutes.
E
But
if
you
have
any
questions
in
continuation
to
what
is
being
said
or
shown
today,
then
you
can
count
on
that
daily
power
programming
call
being
there
indefinitely,
and
that
happens
also
in
Discord
more
details
about
how
to
actually
join
around
on
that
link
that
I
put
there
on
the
slide
a
little
bit
more
about
repository.
We
have
a
few
slides
here,
but
I
will
also
share
the.
E
Actual
directory
structure
itself,
because
I
have
a
little
more
to
say
about
it,
so
the
dev
container
is
very
important
because
that
contains
an
environment
that
is
known
to
work
for
building
the
entire
framework
and
also
for
developing
your
own
applications.
If
you
don't
actually
need
to
build
a
framework
because
you're
not
planning
on
contributing
to
the
framework
itself,.
E
E
E
The
most
interesting
one
to
me
personally
is
the
test
tooling
package,
which
is
the
powerhouse
behind
our
testing
infrastructure
and
also
for
development
of
applications,
writing
tests
for
those
and
for
research
purposes,
and
then
there's
also
the
API
server,
which
is
basically
a
shell
that
loads
plugins
into
it
at
runtime
and
that
that's
what
exposes
apis
that
you
can
use
to
deal
with
or
leverage
the
features.
Some
of
the
features
the
framework.
E
E
But
the
bottom
line
is
that
they're
are
optional
components
here,
you
can
sort
of
pick
and
choose
what
you're
going
to
use,
what
it
is
that
you
need,
and
also
you
can
pick
and
choose
where
your
actual
application
code
sits,
because
it
can
be
loaded
as
a
plugin
either
into
the
API
server
or
it
can
run
on
its
own
and
Rama,
already
explained
much
of
this
and
then
much
higher
quality
than
I
could.
So.
E
E
And
then
yeah
I
think
I'll
I'll
skip
this
one,
because
Rama
explained
this
very
well
about
the
relays.
Node
server,
the
protocols
and
all
that
and
the
development
architecture
like
I,
said
the
most
important
part
of
that
is
test
automation,
which
should
put
a
very
high
emphasis
on
every
pull
request
that
we
have
gets
tests
executed
against
it
in
a
way
that
completely
pristine
ledgers
are
being
pulled
up
that
are
running
in
containers
as
part
of
the
CI
execution
and
then
the
connector
plugins,
the
keychain
plugins.
B
E
But
I
don't
know
if
their
solution
was
comprehensive
and
all-encompassing
and
then
they
they
probably
only
got
the
basic
build
to
run,
but
then
other
things
were
just
not
operational
anyway.
So
the
way
to
go
is
probably
the
virtual
machine
there's
a
a
lot
of
innovation
happening
in
this
space.
That
is
generic
to
software
development.
For
example,
if
you
look
at
GitHub
code
spaces
I
think
they
call
that
feature.
E
E
B
B
Okay,
five
desks
if
hypervisor
Cactus
is
a
web
application
system
designed
to
all
users
to
secure
and
integrate
different
blockchains.
Yes,
basically,
yes,
it's
infrastructure,
and
at
least
we
try
Enterprise
grade
infrastructure
to
integrate
with
different
blockchains
right.
So
it
allows
you
to
create
applications
that
utilize
infrastructure,
different
blockchains,
so
multi,
blockchain
infrastructure.
E
Yeah
I
was
I,
was
giving
around
some
time
to
to
answer,
if
he's
here,
but
I
think
he
may
not
be
so
I'll
just
I'll.
Try
to
chime
in
you
know,
with
the
Safe
Harbor
that
I
may
not
be
the
most
qualified
personal
answer,
but
anyway
the
adapter
kind
of
like
Raphael's
already
explained
it
is
a
providing
the
basic
communication
towards
the
letter
from
the
code
from
the
rest
of
the
for
the
rest
of
the
code
of
the
framework.
E
B
Share
my
screen
on
the
oh
yeah:
absolutely
you
still
have
three
minutes
so
I'm
just
going
to
share
a
few
tips
before
we
start.
So
this
is
the
the
code
right
still
all
the
instructions
on
the
bills
you
want
yarn
run,
configure
which
takes
a
long
time
already
ran
it.
So
I'm
not
going
to
run
it
again
and
you
have
under
the
vs
code.vs
code,
folder
a
set
of
scripts
that
are
very
useful
for
you
to
debug
your
plugins
or
to
execute
files.
B
So
for
that,
you
go
to
this
file,
template
Dot
launch.json
and
you
rename
it
to
launch.json
under
dot
vs
code,
and
what
this
does
is
that
on
vs
code,
it
allows
you
to
have
access
to
this
script,
where
you
can
run
the
current
typescript
test
file
using
tab
or
using
just
with
which
are
test.
Runners
different
test
runs,
and
this
will
be
very
useful.
B
B
Server
is
normally
a
plugin
attention
to
this
cacti
core
such
that
it
can
redirect
calls
so
some
of
the
interesting
packages
as
an
example
are,
for
example,
the
API
server
plugin,
which
is
basically
which,
which
is
basically
the
API
server
backbone,
allows
you
to
collect
to
connect
different
plugins
to
it.
It
redirects
the
calls
to
the
correct
plugin.
B
It
basically
does
all
of
the
heavy
work
on
having
these
Podium
architecture
working.
Then
we
have
some
utilities
like
loggers
cryptographic,
libraries
like
hashing
creation
of
keys,
that's
in
the
cactus
core,
sorry
Cactus
common,
and
then
we
have
the
cactus
core
which
have
the
Consortium
plugins
some
authorization
reporting
registry,
where
you
can
aggregate
different,
plugin
references
and
so
on.
B
We
also
have,
for
example,
a
plugin
that
allows
you
to
interact
with
hash
time
log
contracts
so
for
a
specific
contract,
that's
deployed,
let's
say
on
ethereum
or
on
bezel.
In
this
case
you
have
a
set
of
interfaces
of
apis
that
you
can
use
to
interact
with
that
contract
such
as
deploy
log
Etc.
They
have
a
simple
keychain
that
stores
key
value
pairs
that
you
can
use
to,
for
example,
store
cryptographic
keys
in
a
testing
environment,
not
not
in
production.
B
We
have,
we
have
different,
larger
connectors.
One
of
them
is
hyper
larger
fabric
and
a
package
that
I
use
a
lot
and
I.
Think
it's
very
important
is
the
test
tooling.
So
it
has
test
ledgers
databases,
ipfs
componentization
Etc.
With
this
package,
you
can,
for
example,
create
a
whole
hyperledger
fabric,
Network
programmatically,
very,
very
easy
to
use
very
easy
to
configure
hyperledger
fabric
hyper,
larger
bezel
substrate,
so
for
the
ones
interested
in
the
polka
dot
ecosystem,
which
is
quite
nice.
B
This
is
an
example
where
we
are
creating
a
plug-in
registry,
see
that
the
plugin
registry
is
an
object
that
contains
an
array
of
plugins
and
with
this
registry
you
can
actually
add
plugins
dynamically
right
and
serve
them
into
an
API
server.
So
this
API
server
is
the
interface
between
your
application
and
the
different
plugins
that
you
are
running
within
cacti.
B
Let's
talk
about
the
API
server
first,
so
the
API
server
is
basically
serving
client
requests.
It's
exposed
managed
by
a
cactus
note
what
we
call
Cactus
node
and
it
basically
redirects
calls
to
the
right
plugins.
Okay,
after
you
see
the
supply
chain
example,
it
will
make
a
lot
of
sense.
What
what
this
does
open,
API,
so
open
API
is
a
specification
used
to
describe
restful
web
services
or
the
their
apis
foreign
defines.
What
are
the
end
points
that
are
available
get
in
points.
Posting
points
delete
Etc.
What
are
the
different
authentication
methods?
B
B
B
B
Right
and
if
we
take
the
Json
that
we
have
defined
there,
the
flagger
editor
will
generate
this
interface.
So
basically,
we
expose
the
different
endpoints
of
the
fabric,
connector
right
and
we
get
sdks
generated
with
this
application
that
we
can,
after
that
use
programmatically
again
on
the
supply
chain.
Example.
Peter
will
explain
this,
how
it
works
right
about
the
open
source,
a
project
governance,
so
hyperological
cacti
is
an
open
source
project
such
as
many
hyperledger
or
all
of
hyper-ledger
projects,
which
means
that
everyone
is
welcome
to
participate.
B
Are
these
daily
pair
programming
calls
where,
basically,
if
you
went
to
University,
you
probably
had
those
office
hours
or
adult
sessions
where
you
can
go
to
the
professors
and
ask
them
for
clarifications
on
on
some
homework
or
assignment
it's
basically
the
same
but
for
hyperological
cacti.
So
Peter
gives
a
bit
of
his
time
every
day
to
help
on
different
questions
on
alcata.
You
can
go
for
the
programming
calls
and
it
will
help
you
out,
and
there
is
also
the
maintainer
meetings
and
contributor
meetings
where
you
can
attend
and
see
the
project.
B
B
Another
interesting
thing
is
that
contributing
codes
to
character
is
done
via
pull
requests,
there's
a
whole
process,
that's
documented,
on
the
readme
of
the
project,
but
essentially
you
fart
the
project.
You
create
a
branch,
you
do
your
coding,
you
can
you
do
one
or
more
commits
typically
one
and
you
open
a
pull
request
to
the
the
main
code
base
there
you
define.
B
So,
although
cacti
has
support
from
centralized
corporations,
the
decision-making
process
is
decentralized,
as
in
the
companies
need
to
agree
on
what's
good
for
the
overall
project,
and
so
we
require
two
votes
out
of
n,
in
this
case
three
different
companies
at
the
moment
being
in
the
mainfangers
list
for
the
code
to
be
accepted
right.
So
you
can
see
that
this
specific
pull
requests
already
had
two
approvals.
There
was
one
change
requested
that
you
have
to
address
and
there
are
some
reviewers
that
still
need
to
check
the
code.
B
B
One
very
nice
thing
that
I,
like
a
lot
are
the
test:
ledgers
that
are
implemented
in
us
all
in
all
all-in-one
containers
and
basically
they
allow
you
to
simulate
or
to
execute
test
ledgers
programmatically
very
easily,
and
this
is
done
in
let's
say
two
steps:
the
first
one.
You
have
a
Docker
file
that
has
that
implements
one
of
the
sledges,
for
example,
the
fabric.
All
in
one
has
the
definition
of
fabric
version
1.4
Network.
In
the
fabric
version
to
network.
B
Then
we
publish
these
images
onto
GitHub,
as
so,
they
are
available
to
be
pulled
as
Docker
images,
and
then
we
have
a
piece
of
code
which
is
into
Cactus
test,
tooling,
that
pulls
those
images
and
executes
those
images.
So
the
code
here,
it's
basically
code
using
docker
apis
to
receive
the
image
and
then
to
execute
the
image
to
manage
the
container
and,
for
example,
to
delete
it
at
the
end.
So
in
this
way
we
can
instantiate
the
test.
Ledger
execute
the
test.
Ledger
have
more
code,
we
can
test.
B
This
is
amazing,
because
you
don't
have
too
manually
run
a
network
every
time
you
want
to
test
it
and
if
you
want
to
have
automated
tests
that
create
a
ledger
to
a
specific
function,
this
right
literally
it's
very
easy
to,
and
we
use
this
extensively
in
all
of
our
or
practically
our
for
all.
The
plugins
that
use
a
blockchain
as
the
foundation
is
the
architecture,
the
infrastructure,
all
right
and
I
think
that
that
was
quick.
B
B
Please
try
to
build
a
project
while
we
spend
a
few
first
minutes
on
the
deployment
architecture
flavors,
which
Peter
will
present
after
that
will
present
some
simple
applications
that
you
can
build
using
cacti
and
after
that,
we're
going
to
talk
about
the
example
supply
chain
application
before
the
end
Andrea
will
present
on
his
summer
internship
that
was
implementing
a
cbdc
use
case
using
a
protocol
called
odap
on
cacti
and
finally,
we're
going
to
talk
about
the
future
of
hypometric
cacti
and
answer
any
questions
you
have
Peter.
Can
you
take
it
from
here.
E
The
desktop
then
go
to
this
page.
Yes,
so
I'm
showing
the
same
diagram
but
zoomed
in
what
you
see
here
is
everything
here
is
contained
within
the
developer
machine,
which
is
a
laptop
or
PC
whatever
you
have
at
home,
within
that
you
can
simulate
a
Consortium
which
is
a
set
of
organizations
or
entities
who
want
to
build
some
sort
of
blockchain
TLT
application
together
by
collaborating
and
connecting
their
letters,
their
respective
letters,
and
so
that
that's
what
me
that's?
E
H
E
E
E
These
two
are
very
similar
for
a
reason
so
that
you
can
try
out
how
a
production
deployment
would
work
minus
the
parts
that
are
really
hard
to
simulate,
such
as
an
actual
data
center
and
the
load
balancer
that
has
a
domain
Associated
to
it
and
then
handles
fall
back
and
all
that
and
then
the
way.
Of
course,
this
would
work
in
a
production
environment
is
that
you
would
provision
more
Hardware
resources
to
these
individual
API
servers.
B
B
Okay,
you
could
use
this
for,
for
example,
managing
credentials
that
access
the
blockchains
that
you're
participating
in.
Although
this
example
in
specific
it's
not
meant
for
production,
so
it's
not
secured
enough
and
also
generally
keeping
your
keys
in
memory
is
also
not
the
best
practice.
So
we
also
have
keychain
that
connect,
for
example,
to
Azure
or
more
secure.
Let's
say
a
more
production
ready,
keychain.
B
All
right
so
I
hope
you
were
able
to
get
the
project
building
and
also
to
set
up
the
launch.json
right.
So
it's
basically
duplicating
these
file
template.punch.json
and
renaming
it
also
Json,
then
under
examples,
cactus,
Workshop
examples
which
you
shouldn't
see
now
by
the
way,
because
it's
still
a
pull
request.
It
hasn't
been
merged
onto
the
main
code
base,
but
but
soon
it
will
be.
Hopefully
you
go
to
Source
Main
typescript
and
you
have
the
three
examples
we're
going
to
talk
about.
So
the
first
is
Hell
world.
B
B
B
B
Okay,
so
what
we
did
is
that
we
made
a
pause
request
with
Carl
to
our
localhost
8000,
which
is
where
our
API
server
is
running,
namely
to
the
set
key
CM
endpoint,
which
is
here.
So
we
have
a
breakpoint
the
the
code
stops
here,
so
we
can
inspect
what's
going
on,
so
we
basically
get
the
key
and
the
value.
So
the
key
is
one
two
three
four
and
the
value
is
XYZ,
and
then
what
this
does
and
again.
B
This
is
not
secure
because
we're
basically
taking
the
user's
input
and
sending
it
to
our
internal
spis
without
any
sanitizing.
Do
not
do
this
absolutely
could
I,
basically
setting
the
key
value
pair
and
we
can
see
what
happens
with
the
step
into
so
the
step
into
takes
us
into
the
plug-in
team
chain
memory.ts,
which
is
under
the
factors
plugin
keychain
memory
plugin,
and
it
goes
directly
to
the
set
method.
What
this
does
is
that
it
sets
the
back
end
to
our
key
value,
and
this
back
end
is
simply
a
map.
B
So,
as
you
can
see,
this
is
a
very
simple
plugin
and
then,
additionally,
it
update
the
exposed
metrics
via
Pro
materials.
So
later
you
can,
you
know,
inspect
what
some
modulations
some
updates
to
these
to
this
plugin
in
specific
okay,
we
log
that
and
we've
written
okay.
So
if
we
go
to
our
server,
we
see
the
key
value,
the
new
key
value
log
there,
okay,
so
very
simple,
then
we
can
also.
B
Perform
a
get
to
get
the
value
from
Key
pair
to
perform
a
delete
check
if
it
has
the
key.
So
this
is
a
simple
example
of
how
you
could
use
the
plugin
keychain
and
build
an
application
on
top
of
the
plugin
keychain
right,
be
mindful
that
this
particular
example
does
not
require
you
to
build
the
cacti
project
right.
You
could
have
a
single
Standalone
project
that
has
simply
these
Imports,
so
the
cactus
common,
the
cactus
core,
the
test
tooling
best
tooling.
B
B
So,
let's
stop
this
okay,
so
if
you
you
need
to
do
your
own
Fork
right
and
then
you
go
on
the
project
that
then
you
get
into
the
the
directory.
If
you
do
git
remote
ad
and
then
let's
say
Raphael
and
this
link-
which
you
can
get
via
the
pull
request,
I've
put
on
the
chat,
then
you
should
have-
you
should
be
able
to
get
that
that
Branch,
so
you
add
the
remote,
then
you
would
do
something
like
get
checkout
Rafael
Workshop
examples
to
get
that
code.
B
B
B
B
Basically,
you
define
the
options
you
want
for
your
test,
Ledger
and
then
you
create
the
Ledger,
and
after
these
ledger.start
you
can
interact
with
your
Ledger.
You
can
issue
transactions,
you
can
you
can
read
the
state.
This
is
super
useful
if
you're
developing,
for
example,
a
plugin
that
uses
a
polka
dot
or
a
substrate
based
blockchain,
and
you
want
to
test
it.
So,
instead
of
you,
cloning
from
the
official
repo,
the
test,
Ledger
running
the
test
Ledger
each
time
you
need
to
run
the
test
and
then
deleting
it
and
doing
pruning
Etc.
B
So
this
is
it:
we
import
the
logger
okay
from
Cactus
common.
We
import
two
packages,
or
rather
two
definitions
from
the
test,
tooling,
the
substrate
test
launcher
and
an
interface
for
the
options
that
that
test
slider
takes.
If
we
go
into
the
test,
Ledger
options,
you
see
that
it
takes
several
things:
publish
all
ports
and
I
can
show
you
what
is
in
a
moment
What's
the
load
level
for
your
test
ledger,
so
you
actually
can
run.
B
B
B
But
this
is
the
image
tag
we
want
to
get
okay,
we
want
to
see
the
logs
from
the
container,
so
it's
basically
containers
running
containers
and
then
we
have
a
mapping
of
environmental
variables
environment
variables
that
you
want
to
give
to
send
to
the
test
Ledger
upon
initialization,
which
is
this
map,
so
the
container
name
is
Scotty
cacti
Ledger,
the
working
directory.
Is
this?
B
B
B
B
Okay,
so
I
missed
some
of
the
steps,
but
basically
when
the
start
method
is
called,
we
check
if
the
container
is
present,
if
it's
not,
it
pulls
the
container,
it
sets
the
environment
environment
variables
and
it
does
this
piece
of
magic,
which
is
Docker
dot
run.
It
creates
a
new
container
with
the
image
we've
provided
with
it
and
with
the
options
we
provided.
Okay
once
it
started,
it
emits
an
event.
B
B
E
And
just
a
quick
tip,
if
you
ever
see
this
problem,
that
Raphael
had
just
seen
with
the
debugger
jumping
into
very
strange
places
in
the
code
that
you
don't
recognize,
then
you
most
likely
need
to
rebuild
the
code.
The
easiest
way
to
do,
that
is
to
run
the
configure
script
or
the
watch
script.
Whichever.
E
B
B
No,
no,
no
worries.
Thank
you.
I
I
almost
forgot
about
that.
Yes,
that's
true!
If
the
code
is
not
synchronized,
if
the,
if
the
JavaScript
that
is
compiled
from
the
typescript
is
not
up
to
date,
you'll
see
strange
things
happening
and
you
just
need
to
run
a
speeder
set
yard
and
run
watch,
and
it
will
look
for
updates
on
your
typescript
files
and
do
the
computation.
B
So
this
this
problem
shouldn't
arise,
it's
good
editorize,
so
you
can
already
talk
about
this.
You
could
also
run
tests
other
test
ledgers.
Of
course.
This
is
a
more
comprehensive
example
where
you
have
a
test
from
the
fabric
connector
that
runs
a
transaction,
okay
and
the
way
to
automate.
This
is
to
create
a
cactile
fabric,
test
Ledger
and
the
fabric
connector,
which
is
what
we're
doing
here
so
we're
defining
a
fabric
test
Ledger,
and
we
can
run
this.
This
is
just
not
tap.
D
B
B
D
B
But
the
way
the
way
I
suggest
you
to
start
understanding
cacti
into
more
detail,
is
to
pick
a
plugin
you're
interested
in,
let's
say
the
fabric,
one,
because
I'm
already
here
go
to
test
typescript
integration
and
pick
a
test:
okay,
for
example,
this
one.
Then
you
can
put
a
debug
a
breakpoint
and
run
it
with
just
and
see
and
see
what
happens,
see
what
packages
are
used.
What
is
the
code
flow,
and
this
will
allow
you
to
understand?
Not
only
cacti,
but
also
the
underlying
blockchains
connect.
I
use
it.
B
D
B
Now,
what
I
did
I
entered
on
the
docker
container,
with
Docker
exact,
minus
ID
and
I
listed
the
docker
containers
that
it
has
inside?
So
not
only
it
has
a
Docker
container
for
the
orderer
for
the
peer
two
for
the
peers
for
the
ca
for
each
org,
but
it
also
has
the
chain
code
containers
because
we
deployed
the
smart
contract
the
chain
code
onto
this
container.
So
we
have
like
10
containers
running
inside
our
main
container.
B
B
Our
fabric
connect,
okay
and
the
transact
method
takes
the
transaction
request.
What
is
this?
We
can
see.
Transaction
request
has
an
array
of
endorsing
peers,
that's
optional,
Transit,
that's
optional,
etc,
etc.
It
has
a
channel
name,
contract,
name,
invocation,
type
method,
name.
So
all
the
the
parameters
we
need
to
run
a
transaction
onto
fabric.
B
B
Okay,
so
it
basically
evaluates
our
transactions,
that's
the
success
to
true,
and
then
it
does
a
few
more
things
that
we
don't
need
to
talk
into
the
data.
Okay
and
that's
basically
what
happens
and
it
does
more
than
one
transaction.
That's
why
it's
going
to
the
breakpoint
again
at
the
end
of
all
of
this
after
some
transactions
it
it
does
some
basic
testing
so
that
you
know
our
response
has
an
asset
or
our
other
response.
B
We
get
from
the
server
depicts
an
asset,
what
we
Define
as
an
asset,
that
it
has
a
defined
attribute
that
is
the
owner,
etc,
etc,
and
at
the
end
it
tears
down
the
The
Ledger
the
test
light
should
it
create.
So
if
we
go,
if
we
do
Docker
PS,
it
still
is
still
here,
but
when
the
test
executes
completely,
it
should
shouldn't
be
so
it's
gone
which
allows
you
to
create
industry
ledgers
at
will.
B
B
B
E
Thank
you,
Rafael
I
was
really
great
because
it
showed
a
lot
of
the
debugging
and
how
that's
done
not
just
on
the
application
Level
but
tape
it
in
the
framework
score
itself
as
well.
So
I
just
wanted
to
highlight
that,
because
that
was
something
that
I
was
going
to
highlight
as
well,
but
now
I
don't
have
to.
E
E
E
E
E
And
so
the
cool
thing
is
that
you
can
try
and
debug
this
at
home
on
relatively
low
free
source
usage
scenarios,
and
you
can
modify
it
as
you
see
fit.
You
can
use
it
as
a
template
for
your
own
applications
and
those
don't
have
to
be
a
part
of
the
framework.
The
only
reason
why
this
code
is
just
happens
to
be
within
the
Frameworks
kit
repositories,
because
that's
very
developed
in
this
way.
E
So
this
is
the
high
level
overview
and
then
I
just
wanted
to
show
that
there's
the
UI
code,
which
has
a
supply
chain,
API,
API
client
object
which
comes
from
this
package.
That
is
called
the
business
logic
plugin,
and
this
package
contains
the
code
that
gets
loaded
into
the
API
server
next
to
the
connector
plugins.
E
So
this
example
has
three
API
servers,
all
of
which
are
loaded
up
with
connector
plugins
for
all
three
of
the
letters
and
also
this
business
logic
plugin,
which
is
the
one
that
ultimately
handles
the
data
management,
which
you
basically
see
here.
One
example
of
it
that
invokes
the
contract
to
store
the
data
on
the
letter,
and
if
you
want
to
write
your
own
plugin
either
for
something
like
a
connector
interface
or
for
actual
business
logic,
you
can
do
so.
E
It's
basically
just
about
implementing
these
interfaces
that
you
can
import
from
the
core
API
package.
I
think
Rafael
also
touched
on
these,
so
I
don't
want
to
say
the
same
things
again,
but
it's
worth
repeating
that
creating
a
plugin
is
very
easy.
You
just
have
to
implement
these
interfaces,
which
are
also
pretty
simple.
E
Basically,
all
this
does
is
instantiates
and
points
with
signing
credentials
for
the
letters
and
some
other
data,
such
as
the
log
level
and
the
keychain
ID,
and
then
it
wires
these
endpoints
up.
So
there's
been
the
API
server
gets
started
and
these
are
there
and
that's
what
makes
it
possible
to
to
reach
these
through
the
API
client
later
on
and
I
think
I'll
just
stop
there
with
this
example.
E
E
B
I
Yeah,
perfect,
okay,
so
we're
going
to
divide
this
part
in
in
two
different
pieces.
Firstly,
I'll
present
the
audub
or
satp,
we'll
explain
that
in
a
in
a
minute
and
then
a
cbdc
bridging
use
case
between
hyperledger
Fabric
and
a
hyperledger
basil
Network.
So,
first
of
all,
just
a
few
words
about
me:
I'm
Andre,
a
PhD
student
from
Lisbon
I,
have
been
researching
blockchain,
proper
ability
and
contributing
for
cacti
for
about
a
year
now
and
I'm
really
interested
in
collaborating.
I
So
what
is
odap
or
satp
so
Rama
also
talked
a
little
bit
about
this
odap
is
is
under
specification
that
the
ITF,
the
internet
engineering
task
force,
the
name-
has
changed
recently
from
odap
open,
Digital
asset
protocol
to
secure
asset
transfer
protocol.
This
is
why
we
still
have
these
two
names
here.
In
cacti
we
still
have
the
the
plugin
with
odap,
so
I'll
use
that
name
here
today.
So
odap
is
basically
an
asset
transfer
protocol
that
is
suited
to
work
either
on
blockchains
or
Legacy
systems.
I
Right
here,
we're
focused
on
more
on
blockchains
and
the
reason
why
we
choose
to
work
on
Old
outputs
because
of
standardization.
As
of
today,
there
are
dozens.
There
are
probably
hundreds
of
interoperability
solutions
that
are
really
targeted
to
specific
use
cases
or
specific
ledgers,
but
they
are
not
really
extendable
to
other
other
blockchains
or
other
Solutions.
I
So
we
need
to
work
on
this
standardization
of
cross-chain
communication,
and
this
is
why
we
use
ODOT
and
again,
as
Rama
told
told
us
in
the
beginning,
this
is
not
a
an
asset
transfer
protocol
that
runs
between
these
two
networks
directly.
We
leverage
these
two
gateways
or
a
Gateway
for
each
Network,
and
each
of
these
gateways
has
read
and
write
access
to
the
ledger.
So
basically
the
ledgers
trust
these
gateways
to
make
operations,
and
then
these
gateways
run
in
between
odap
or
satp.
I
D
I
This
case
it
is
odap
or
satp,
so
just
this
is
the
sequence
diagram
of
a
vodaf.
This
is
a
lot
of
detail,
but
don't
lose
yourselves
in
so
many
messages
back
and
forth.
The
key
idea
here
is
that
it
has.
In
the
beginning,
as
Raphael
said,
when
we
have
an
asset
transfer
protocol,
we
mainly
have
a
lock
and
delete
in
the
in
the
source
Ledger
where
that
asset
is
and
then
we
kind
of
recreate
or
create
the
representation
of
that
asset
in
the
Target
blockchain.
I
So
basically,
you
have
the
source
code
for
this
plugin
and
you
can
instantiate
Gateway
there
and
the
idea
to
instantiate
the
Gateway
is
that
you
don't
actually
there's
this
plugin
load
up
Gateway.
This
is
an
abstract
class
which
has
basically
the
Gateway
Logic,
the
satp
or
odap
logic
there.
So
it
cannot
be
directly
instantiated.
I
It's
specifically
a
fabric?
Gateway.
Let's
say
we
have
here.
You
know
name
dltid.
This
is
like
the
Ledger
compatibility
this
case
we
can
say
that
I
only
talked
to
gateways
that
are
connected
to
a
dlt2.
We
have
an
instance
ID
an
ipfs
path.
This
is
just
for
logging
purposes,
not
really
important
right
now
we
have
fabric
specific
things,
since
this
is
a
fabric,
Gateway
signing
credentials,
channels,
the
the
chain
code
name
that
will
be
accessed,
and
then
we
have
things
that
can
be
also
extended
classes.
I
That
can
also
be
extended
for
specific
use
case
implementations.
Of
course,
we
might
need
to
do
different
checks
if
we
have
a
supply
chain.
Example.
Then,
if,
when
we
have
a
a
cbdc
bridging
example,
so
now
into
the
the
use
case
that
we
built
on
top
of
this-
and
this
was
in
the
context
of
a
hyperledger
mentorship's
project,
I
was
the
mentee.
My
mentors
were
imra
in
Laszlo.
I
Basically,
if
you
want
to
actually
see
the
cbdc
Prototype,
you
can
check
inverse
presentation
on
hyperledger
global
forum
this
in
September.
But
the
idea
here
is
that
we
have
a
core
cbdc
Ledger
based
on
a
hyperledger
fabric
Network.
This
can
be
maintained
by
a
Consortium
of
central
banks,
financial
institutions
and
they
manage
the
cbdc
in
in
this
letter,
and
then
we
have
other
ledgers.
This
can
be
retail
businesses,
ledgers
that
serve
clients
through
the
exposure
of
some
services.
I
To
basically
clients
can
you
know,
access
those
services
and
of
course
they
need
to
pay
and
if
they
need
to
pay,
they
need
access
to
the
core.
Cpc
ledger
so,
and
a
user
needs
to
be
able
to
transfer
tokens
from
one
ledger
to
the
other
and
the
other
way
around
as
well.
So
what
we
did
here
is
basically,
of
course,
building
a
bridge
with
hyperledger
cacti
and
implementing
a
gate,
a
Gateway
for
each
Ledger.
I
So
as
an
example,
we
developed
two
different
smart
contracts
or
chain
code
in
each
in
each
Ledger.
We
have
the
cbdc
chain
code
or
smart
contract
which
basically
encompasses
the
actual
logic
of
the
cbdc.
So
the
cbdc
is
a
central
bank.
Digital
currency,
I
didn't
said
that
just
think
of
it
as
a
token,
if
you
don't
actually
know
a
lot
of
that
in
detail.
I
I
The
cbdc
chain
code
will
create
an
asset
reference
that
represents
this
50
cbdc
and
then
Alice
can
use
the
ID
of
the
asset
reference
to
talk
to
the
bridge,
in
this
case,
to
Gateway,
One
and
say
Hey
I
want
to
bridge
out
this
amount
of
tokens
with
this
asset
reference
ID,
so
Gateway
One
will
run
out.
As
we
said,
this
will
Encompass,
locking,
deleting
and
then
creating
a
representation
of
this
asset
reference
in
the
bezel
Ledger.
I
The
asset
reference
smart
contract
knows
how
knows
what
this
asset
reference
is
and
knows
that
it
needs
to
Mint
50
cbdc
to
Alice's
address
in
the
cvdc
smart
contract.
So
while
this
will
will
now
have
50
cbdc
to
use
in
a
hyperledger,
bezel
Network
and
of
course,
if
she
wants
she
can
she
can
Bridge
back
these
tokens
back
to
the
to
the
core
to
the
cbdc
core
Ledger.
I
I
In
the
other
examples,
we
can
create
API
servers
and
connect
different
plugins
there,
and
basically
the
the
endpoints
that
are
exposed
by
those
plugins
will
also
be
explode,
exposed
to
the
exterior,
and
so
we
have
the
ldap
plugin,
which
is
basically
the
logic
of
the
Gateway
in
the
in
this.
In
the
in
this
left
side,
we
have
a
hyperledger
path.
We
can
a.
I
I
So
if
you
want
to
to
try
that
there's
this
cbdc
bridging
app
file
where
basically,
we
Define
here
the
API
servers
and
this
API
servers
have
this
plugin
Registries
and
these
plugin
Registries
are
basically
a
set
of
plugins
that
are
that
will
be
exposed
by
this
API
server.
So,
on
the
client
side,
we
have
the
fabric
Gateway,
the
fabric,
connector,
the
fabric
Gateway
and
the
ipfs
connector,
and
on
the
server
side
we
have
the
best
zoo,
Ledger,
connectors,
the
ipfs
and
the
odap
Gateway
as
well.
I
And
then,
when
the
API
servers
are
running,
we
can
deploy
our
smart
contracts
and
we're
good
to
go.
We
can
try
the
application,
calling
the
different
endpoints
and
so
on.
So
there's
actually
an
example,
a
front-end
that
you
can
you
can
try
and
I
have
here
also
another
link,
basically
for
these
instructions
right
here.
If
you
would
like
to
test
that
it's
in
this.
A
I
Okay,
so
the
idea
here
is
that
in
in
the
fabric
side,
we
have
this
cbdc
chain
code.
This
is
actually
implemented
as
a
sort
of
erc20
smart
contract
on
the
fabric
side.
So
we
kind
of
emulate
that
and
in
in
fabric
we
don't
have
that
guess
gas
issue.
In
the
business
side
we
have
so
yeah.
That's
that's!
Basically,
it.
I
Of
course,
in
in
the
fabric
side,
we
need
the
the
author
authentication
authorization.
This
is
a
little
bit
more
complex
than
I
that
I
showed
here.
It
has
multiple
organizations
with
different
authorizations
for
for
each
one
of
these
actions
that
can
be
performed
either
by
the
bridge
or
by
the
users.
So
yeah,
it's
it's
explained
a
little
bit
better
in
the
in
the
documentation.
I
Exactly
Shane,
it's
it's
that
and
before
destroying
the
asset
on
the
source
chain,
we
we
have
before
a
lock,
so
we
locked
the
asset
before
then
and
then
we
destroy
it.
It's
like
the
it's
like
preparing
for
the
actual
destruction
before
burning
effectively
the
asset
foreign
yeah
I
can
I
can
put
the
the
link
for
the
video
here.
B
So
in
the
fabric
side
you
don't
necessarily
pay
fees
on
the
public
Ledger
you
you'll
pay
fees,
so
the
cost
would
be
the
cost
of
the
interoperability
mechanism
of
operating
it.
But
cacti
doesn't
charge
fees
right,
plus
the
cost
of
the
transactions
on
the
public
network
and
on
fabric,
which
is
zero.
Hey.
B
J
The
best
just
just
to
say,
minor
note
of
clarification.
This
is
intended
to
connect
private
ledgers,
mostly,
and
if
you
have
busy
on
the
right
side
in
a
private
settings,
save
it
click
or
ibft
I
believe
is
what's
supposed
to
be
for
production
now
and
fabric
on
the
left
side,
then
this
is
not
actually
question
of
gas
and
the
like
is
just
sizing
your
network
for
the
given
performance
guarantees,
and
essentially
we
can
do
that
for
fabric
as
well
as
diesel.
J
So,
while
on
the
technical
level,
there
is
a
gas
cost
on
the
right
side,
it's
it's
really
just
a
technicality
stemming
from
using
ethereum
for
for
setting
up
a
consortial
network.
You
can
try
this
whole
thing
with
a
public
network,
but
I
can't
really
imagine
a
central
bank
who
wants
to
see
their
assets
on
on
a
public,
not
public
network
reached
out.
That
would
be
a
quite
that
wouldn't
be
a
long-running
bridge
service.
Let's
just
say
that.
E
A
Don't
there's
no
hard
cut
off?
No,
no
we're
this.
This
is
your
Workshop
Peter
and
Raphael.
This
is
awesome,
and
if
we
want
to
keep
going,
we
can
keep
going
I,
don't
I,
there's
no
hard
cut
off.
The
clock
is
not
going
to
shut
down
the
zoom.
So
if
there
are
more
questions
or
if
you
guys
want
to
present
more
clarifying
information
by
all
means,
this
has
been
a
great
Workshop,
so
I
don't
want
to
stop
it.
E
Right
so
the
future
of
the
project
is
to
grow
the
community.
That's
the
most
important
part.
We
need
more
contributors
because
of
the
aforementioned
scaling
issue
with
a
letter
fragmentation.
So
we
need
your
help
and
that
is
I've
released
a
few
items
feature-wise
that
we
are
planning
on
implementing
it's
mostly
a
personal
wishlist
of
mine,
so
there's
other
items
on
the
roadmap
from
other
maintainers
and
the
roadmap
is
constantly
evolving,
as
we
are
hammering
out
details
especially
around
how
to
manage
the
joining
forces
of
the
beaver
and
former
cactus
maintainers.
E
E
And
then,
once
we
figured
out
that
what
goes
into
2.0,
then
we
will
issue
with
2.00
Alpha
release,
which
will
be
the
first
release
ever
that
will
contain
the
beaver
and
the
cactus
source
code
together,
which
is
what
makes
up.
Cacti
identity
is
very
important
and
we
have
not
had
enough
time
to
work
on
it.
We
do
have
some
things
like
the
keychain
plugins,
but
I
personally
want
to
take
it
much
further.
E
I
want
to
be
able
to
bootstrap
consortiums
with
different
truss
anchors,
meaning
that
the
original
key
exchange
of
the
nodes
would
cut
would
be
able
to
come
from
different
sources
such
as
an
indie,
Ledger
or
chasing
web
signatures.
X51I
anything
else.
This
also
has
to
be
a
part
of
the
plugin
architecture,
in
the
sense
that
I
don't
want
any
of
this
hard-coded
I.
Don't
want
us
to
find
ourselves
in
a
situation
next
year,
where
we
sort
of
picked
a
winner,
quote,
unquote
and
then
realized
later
on
that
we
should
have
picked
another
winner.
E
E
E
We
do
have
some
of
this
in
place,
but
it's
a
very
rudimentary
compared
to
what
I
want
us
to
have.
So
that's
definitely
on
the
roadmap
as
well,
and
we
have
a
call
to
action
here,
which
is
just
a
bunch
of
links
and
me
saying
again
that
we
are
looking
for
contributors
and
you're
always
welcome
to
join
the
power
programming
sessions
and
I'm,
not
sure
if
Rafael
wanted
to
show
order
after
the
rest
of
the
slides
or
if
he
wanted
me
to
talk
about
these
things.
E
B
E
A
B
Very
yeah,
so
thanks
Peter,
another
call
to
action
is
if
you're,
researching
or
learning
about
blockchain
interoperability.
If
you're
a
student,
if
you're
interested
in
the
area
cacti
is
an
excellent
platform
and
Cactus
and
Weaver
to
do
research
into
these
areas.
We
have
a
series
of
papers
that
were
published
on
our
on
its
way
to
being
published
on
different
plugins
of
of
cacti
or
interoperability,
architectures
or
systematizations,
for
example,
the
example.
B
B
B
More
papers,
flash
resources,
those
are
mainly
from
Weaver
folks.
They
have
a
very
interesting
paper
which
is
very
valuable
observation
of
permission.
Ledgers
I
really
like
that
paper
because
it
seems
to
solve
or
propose
a
very
compelling
solution
for
interoperability
across
private
blockchains,
which
is
kind
of
tricky
because
their
state
is
not
public
or
open
or
transparent
by
default.
B
So
you
need
to
do
some
clever
tricks
to
allow
for
proof,
verification
on
on
the
counterparty
blockchain,
the
presentation
on
UE
by
suzumu
under
technology
they
use
ipcs,
so
they're
mainly
interoperating
across
public
blockchains,
but
in
in
specific
cases
where
you
don't
have
this
transparency
by
default.
It's
a
bit
tricky,
so
please
feel
free
to
collaborate
with
us.
You
literally
just
need
to
show
up
on
on
the
channel
and
say
you
want
to
contribute
or
to
learn
into
more
detail.
B
We
are
researchers,
programmers
and
we
we
do
different
tasks.
We
do
a
bit
of
evidence
please
reach
out
if
you're
interested
next
slide,
please
a
huge
huge,
huge
thanks
to
Monica
Gomez,
which
did
a
lot
of
the
heavy
pulling
to
put
this
workshop
together
and
very,
very
visually
appealing.
Is
you?
Can
I
hope
confirm
and
also
to
have
enough?
We
did
a
preliminary
version
of
the
hello
world
example.
B
B
A
A
A
Question
in
chat:
why
use
cacti
over
Firefly?
What
are
the
differences?
What
is
the
primary
purpose
of
cacti
and
how
does
it
differ
from
Firefly
and
I
think
we
lost
Nico
earlier
because
he
had
a
conflict,
so
he
couldn't
stay
throughout
the
entire
session
Daniel.
If
you'd
like
you,
can
also
post
that
on
Discord,
either
in
the
Firefly
or
in
the
in
the
cacti
channels
and
and
I'm
sure
there'll
be
a
firefly
person
where
I
was
able
to
answer
that,
for
you.
B
Yeah
I
think
that's
I,
I,
cleanser,
From
cacti's
perspective
I.
Think
that's
a
very
good
question,
because
there's
a
lot
of
synergies
between
the
projects
it
seems
Firefly
is
also
trying
to
abstract
the
infrastructure.
So
you
can
focus
at
the
application.
Level
from
my
understanding,
cacti
has
more
connectors.
It's
focused
a
bit
more
or
maybe
a
lot
more
I,
don't
know
in
detail
on
the
infrastructure
level,
whereas
Firefly
is
more
focused
on
the
application
Level,
as
you
could
have
seen.
B
For
example,
they
have
really
nice
user
interfaces
that
should
come
for
free
for
for
their
or
for
free,
maybe
not
for
free
right,
but
allows
you
to
deploy
a
user
interface
more
easily,
as
opposed
to
have
some
templates
and
they
have
a
set
of
plugins
around
the
asset
transfers
and
the
decentralization
of
the
Consortium.
So
I
think
those
folks
are
more
focused
on
the
higher
level
part
of
the
stack,
whereas
we
focus
more
on
infrastructure.
E
E
E
If
you
have
worries
about
putting
in
effort
into
a
feature
or
an
improvement
that
you're
not
sure
if
it
would
be
accepted
or
welcomed
because
of
for
whatever
reasons,
then
what
you
can
do
is
open
an
issue
first
and
say:
I,
think
this
feature
is
missing
or
I
think
there's
a
bug
there
I
would
like
to
fix
it.
I
would
like
to
fix
it
or
implement
it
in
this
specific
way
and
then
ask
the
maintainers
to
chime
in
on
that
which
would
then
sort
of
give
you
a
preliminary
approval
on
the
conceptual
level.
E
This
doesn't
guarantee
that
your
pull
request
will
go
through
the
first
time
you
submit
it,
but
it
does
guarantee
that
no
one
will
come
back
and
say:
oh
I
disagree
with
the
idea
in
general.
So
then,
if
you
go
through
this
little
extra
step
in
the
beginning
to
get
the
buy-in
from
the
maintainers
in
advance,
then
you
can
be
sure
that
that
verse,
you
would
have
to
refactor
some
things
in
your
pull
request
that
some
maintainers
may
disagree
with,
but
not
on
a
conceptual
level.
A
B
B
But
the
logs
we're
talking
about
are
hopefully
not
those,
but
it
always
depends
on
the
implementation
so
bugs
the
fact
that
there
are
bugs
in
software
might
lead
to
permanent
local
funds.
In
the
case
of
a
bridge,
we
basically
want
the
bridge
contract
to
act
as
an
escrow,
so
you
send
funds
to
that.
Smart
contract
and
the
breach
keeps
the
funds,
so
the
funds
are
not
are
not
what
per
se
they
are
held
into.
B
The
bridge
account
that's
what
we
defined
by
a
lot,
and
hopefully
the
bridge
can,
on
the
other
blockchain
on
the
counterparty
blockchain.
The
bridge
contract
can
recognize
that
there
has
been
a
lot
a
successful
lot
and
means
some
tokens
for
you
that
are
backed
by
the
tokens
that
you
want.
Okay-
and
this
happens
with
the
help
of
relayers,
with
specific
protocols
for
interoperability,
but
the
general
way
it's
done.
It's
like
that.
Now
there
can
be
a
variety
of
attacks
to
this
scheme
that
allows
you
to,
for
example,
mint
assets
on
the
counterparty
blockchain.
B
Even
if
you
didn't
clock
as
assets
on
the
on
the
first
blockchain
and
those
are
cross-chain
attacks
and
those
are
the
ones
responsible
for
the
cross
chain,
hacks
that
happened
to
Bridges
and
has
resulted
in
more
than
one
and
a
half
billion
dollars
in
Damages
only
in
the
last
few
months.
So
it's
a
quite
serious
problem,
and
that
is
why
interoperability
research
is
so
relevant
because
it's
holding
up
a
lot
of
value
and
it
has
a
huge
attack.
Surface.
E
And
that's
why
I'm
paranoid
about
test
automation
or
not
paranoid,
but
very
insistent
that
insistent,
yes,
but
also
paranoid
that
something
bad
could
happen.
And
therefore
we
need
to
insist
on
a
very
thorough
test.
Automation
process,
which
then
also
feeds
into
helping
the
research
make
get
done
faster
and.
B
E
The
researchers
don't
have
to
spend
as
much
time
with
the
basic
mechanics
of
pulling
up
letters.
For
example,
then
they
can
spend
more
time
thinking
about
what
they
are.
The
best
at
is
researching
the
security
properties
of
whatever
it
is
that
is
getting
examined
so
I
think
that's
a
huge
net
positive
there
as
well.
A
E
He
kind
of
answer
your
question.
There
quote:
unquote,
almost
anything
is
possible
through
plugins,
but
also
just
as
for
a
little
more.
It's
not
the
only
type
of
solution
that
you
can
create
with
the
framework
there's
plenty
of
others.
For
example,
the
supply
chain
app
that
I
was
demoing,
was
not
doing
any
Atomic
slopes.
That
was
just
showing
you
data
on
three
different
lectures
and
inserting
data
also
onto
three
different
ledgers.
But
there
was
no
cross
chain
angle
there.
Apart
from
the
data
sharing
across
the
letters.
B
Yeah,
if
I
can
complement
that
Cactus
is
modular
and
allows
you
to
do
very
flexible
things.
We
have
data
transfers
which
you
can
see
on
the
supply
chain
app.
So
basically
the
app
is
transferring
data
across
Chains
No
double
spend
protection
needed.
Let's
say
we
have
asset
transfers
with
a
plug-in
and
represented
all
that
with
gateways
which
implements
our
satp
protocol,
which
we're
trying
to
standardize,
and
we
have
asset
exchanges
with
short-time
contracts,
so
you
deploy
as
a
short
time
contract,
and
then
you
use
the
cacti
plugin
to
interact
with
that
contract.
B
So
you
could
build
interfaces
on
top
of
it.
You
could
build
automation
pipelines
on
top
of
it.
It's
like
really
anything
because
CAT5
is
supposed
to
support
general
purpose
interoperability.
So
if
you
want
to
create
your
plugin
that
conjugates
an
asset
transfer
with
data
transfers,
so
imagine
there's
some
precondition
for
you
to
do
an
asset
transfer
based
on
some
data.
Yes,
you
can
do
it
and
that's
quite
flexible,
and
that's
also
why
we
welcome
research.
So
with
such
enthusiasm,
we
think
it's
a
really
good
place
and
thanks
to
Peter's
push
on
this.
B
So
if
you
want
to
have
your
codes
Incorporated
on
the
main
code
base,
you
need
to
have
the
code
needs
to
be
clean,
needs
to
pass.
The
test
needs
Not,
To,
Break
cacti,
hopefully
preferably,
and
it
should
also
come
with
some
tests
right
and
if
it
comes
with
some
tests,
you
basically
have
your
paper
evaluation
for
free,
it's
not
for
free.
You
have
to
do
it
right,
but
it's
encoded
on
the
test
right.
You
can
do
some
performance
measurements.
You
can
do
some
attacks,
simulated
attacks
on
the
test
files,
so
it
truly
helps.
B
B
So
that's
also
a
good
topic
for
research.
In
principle,
the
transactional
throughput
will
be
limited
by
the
Solace
chain,
but
here
you
have
an
extra
component
which
is
cacti,
which
is
orchestrating
the
transactions
and
could
introduce
and
will
introduce
some
latency
right
because
you
you
reach
from
a
ledger,
then
you
need
to
do
some
processing
and
only
that
you
submit
a
transaction
on
the
surpluser.
B
D
A
A
As
well
as
the
YouTube
video
and
we're
going
to
include
those
links
in
the
YouTube
video
as
well,
so
no
one
gets
lost,
we
don't
want
there
to
be
a
lost
Fidelity
there,
but
thank
you
everyone
for
joining
us
and
thank
you
to
the
workshop
presenters.
This
was
great
and
we
really
appreciate
everyone
also
check
out
the
hyperledger
Discord,
the
hyperledger
wiki,
and
that
will
be
in
the
thank
you
email
as
well.