<s>
Avalanche	B-Application
is	O
a	O
decentralized	O
,	O
open-source	B-License
proof	B-Protocol
of	I-Protocol
stake	I-Protocol
blockchain	B-Application
with	O
smart	B-Application
contract	I-Application
functionality	O
.	O
</s>
<s>
Avalanche	B-Application
began	O
as	O
a	O
protocol	O
for	O
solving	O
for	O
consensus	B-Operating_System
in	O
a	O
network	O
of	O
unreliable	O
machines	O
,	O
where	O
failures	O
may	O
be	O
crash-fault	O
or	O
Byzantine	B-Operating_System
.	O
</s>
<s>
The	O
protocol	O
's	O
fundamentals	O
were	O
first	O
shared	O
on	O
the	O
InterPlanetary	B-Protocol
File	I-Protocol
System	I-Protocol
(	O
IPFS	B-Protocol
)	O
in	O
May	O
2018	O
by	O
a	O
pseudonymous	O
group	O
of	O
enthusiasts	O
going	O
by	O
the	O
name	O
"	O
Team	O
Rocket	O
"	O
.	O
</s>
<s>
Avalanche	B-Application
was	O
later	O
developed	O
by	O
researchers	O
from	O
Cornell	O
University	O
led	O
by	O
Emin	O
Gün	O
Sirer	O
and	O
doctoral	O
students	O
Maofan	O
"	O
Ted	O
"	O
Yin	O
and	O
Kevin	O
Sekniqi	O
.	O
</s>
<s>
Following	O
the	O
research	O
stage	O
,	O
a	O
startup	O
technology	O
company	O
was	O
founded	O
to	O
develop	O
a	O
blockchain	B-Application
network	O
that	O
would	O
meet	O
finance	O
industry	O
requirements	O
.	O
</s>
<s>
In	O
March	O
,	O
2020	O
,	O
the	O
AVA	O
codebase	O
(	O
Developer	O
Accelerator	O
Program	O
or	O
AVA	O
DAP	O
)	O
for	O
the	O
Avalanche	B-Application
consensus	B-Operating_System
protocol	O
was	O
released	O
as	O
open-source	B-License
and	O
became	O
available	O
to	O
the	O
public	O
.	O
</s>
<s>
In	O
November	O
2021	O
,	O
following	O
an	O
agreement	O
with	O
Deloitte	O
to	O
improve	O
U.S.	O
disaster-relief	O
funding	O
,	O
the	O
Avalanche	B-Application
blockchain	B-Application
moves	O
into	O
the	O
top	O
10	O
cryptocurrencies	O
in	O
terms	O
of	O
capitalization	O
.	O
</s>
<s>
In	O
August	O
2022	O
,	O
whistleblower	O
"	O
Crypto	O
Leaks	O
"	O
published	O
a	O
report	O
accusing	O
Ava	O
Labs	O
of	O
secret	O
deals	O
with	O
a	O
law	O
firm	O
aimed	O
at	O
legally	O
destabilizing	O
Avalanche	B-Application
's	O
competitors	O
.	O
</s>
<s>
In	O
January	O
2023	O
,	O
a	O
partnership	O
was	O
announced	O
between	O
Avalanche	B-Application
and	O
Amazon	O
to	O
improve	O
Avalanche	B-Application
's	O
infrastructure	O
and	O
decentralized	O
application	O
ecosystem	O
.	O
</s>
<s>
In	O
February	O
2023	O
,	O
Indian	O
game	O
streaming	O
platform	O
Loco	O
has	O
teamed	O
up	O
with	O
the	O
Avalanche	B-Application
blockchain	B-Application
.	O
</s>
<s>
Avalanche	B-Application
(	O
AVAX	O
)	O
is	O
the	O
native	O
token	O
of	O
Avalanche	B-Application
,	O
traded	O
on	O
the	O
X-Chain	O
.	O
</s>
<s>
The	O
protocol	O
has	O
four	O
basic	O
interrelated	O
mechanisms	O
that	O
compose	O
structural	O
support	O
of	O
the	O
consensus	B-Operating_System
tool	O
.	O
</s>
<s>
These	O
four	O
mechanisms	O
are	O
Slush	O
,	O
Snowflake	O
,	O
Snowball	O
,	O
and	O
Avalanche	B-Application
.	O
</s>
<s>
Although	O
the	O
original	O
paper	O
focused	O
on	O
a	O
single	O
protocol	O
,	O
namely	O
Avalanche	B-Application
,	O
it	O
implicitly	O
introduced	O
a	O
broad	O
spectrum	O
of	O
voting-based	O
,	O
or	O
quorum-based	B-General_Concept
consensus	B-Operating_System
protocols	I-Operating_System
,	O
called	O
the	O
Snow	O
family	O
.	O
</s>
<s>
While	O
Avalanche	B-Application
is	O
a	O
single	O
instantiation	O
,	O
the	O
Snow	O
family	O
seems	O
to	O
be	O
able	O
to	O
generalize	O
all	O
quorum-based	B-General_Concept
voting	O
protocols	O
for	O
replica	B-Architecture
control	O
.	O
</s>
<s>
Unlike	O
prior	O
quorum-based	B-General_Concept
work	O
,	O
the	O
Snow	O
family	O
enables	O
arbitrarily	O
parametrizable	O
failure	O
probability	O
at	O
the	O
quorum	B-General_Concept
intersection	O
level	O
.	O
</s>
<s>
Standard	O
quorum-based	B-General_Concept
protocols	O
define	O
this	O
failure	O
probability	O
to	O
be	O
precisely	O
zero	O
,	O
but	O
by	O
introducing	O
errors	O
in	O
the	O
quorum	B-General_Concept
intersection	O
,	O
a	O
larger	O
set	O
of	O
consensus	B-Operating_System
protocol	O
design	O
is	O
available	O
.	O
</s>
<s>
Consensus	B-Operating_System
protocols	I-Operating_System
are	O
the	O
basis	O
for	O
the	O
state	B-Operating_System
machine	I-Operating_System
replication	I-Operating_System
problem	O
,	O
which	O
aims	O
to	O
enable	O
a	O
set	O
of	O
machines	O
to	O
achieve	O
agreement	O
over	O
a	O
network	O
even	O
when	O
a	O
subset	O
of	O
the	O
machines	O
are	O
corrupted	O
.	O
</s>
<s>
There	O
are	O
two	O
major	O
families	O
of	O
consensus	B-Operating_System
protocols	I-Operating_System
to	O
date	O
-	O
classical	O
consensus	B-Operating_System
and	O
Nakamoto	O
consensus	B-Operating_System
protocols	I-Operating_System
.	O
</s>
<s>
The	O
first	O
achieves	O
consensus	B-Operating_System
through	O
quorums	B-General_Concept
,	O
thus	O
requires	O
voting	O
.	O
</s>
<s>
Famous	O
instantiations	O
of	O
this	O
are	O
Paxos	B-Operating_System
(	O
in	O
the	O
crash-fault-tolerant	O
environment	O
)	O
and	O
PBFT	B-Operating_System
in	O
the	O
Byzantine-fault	O
tolerant	O
case	O
.	O
</s>
<s>
If	O
sufficient	O
votes	O
cast	O
by	O
the	O
various	O
replicas	B-Architecture
are	O
accumulated	O
(	O
typically	O
collected	O
through	O
elected	O
leader	O
replica	B-Architecture
)	O
,	O
then	O
a	O
quorum	B-General_Concept
is	O
achieved	O
,	O
and	O
thus	O
agreement	O
.	O
</s>
<s>
The	O
second	O
family	O
,	O
pioneered	O
by	O
Satoshi	O
Nakamoto	O
and	O
Bitcoin	B-Protocol
is	O
that	O
of	O
Nakamoto	O
consensus	B-Operating_System
.	O
</s>
<s>
Unlike	O
quorum-based	B-General_Concept
protocols	O
,	O
machines	O
operating	O
an	O
instance	O
of	O
Nakamoto	O
consensus	B-Operating_System
achieve	O
agreement	O
on	O
transactions	O
by	O
downloading	O
the	O
longest	O
chain	O
(	O
typically	O
called	O
a	O
fork	O
)	O
.	O
</s>
<s>
In	O
Bitcoin	B-Protocol
,	O
the	O
longest	O
chain	O
is	O
verified	O
by	O
ensuring	O
that	O
it	O
is	O
the	O
one	O
with	O
the	O
highest	O
degree	O
of	O
work	O
(	O
or	O
proof	O
of	O
work	O
)	O
.	O
</s>
<s>
Snow	O
,	O
while	O
quorum-based	B-General_Concept
,	O
seems	O
to	O
be	O
a	O
universal	O
generalization	O
of	O
all	O
quorum-based	B-General_Concept
protocols	O
.	O
</s>
<s>
Unlike	O
prior	O
work	O
which	O
requires	O
that	O
quorums	B-General_Concept
be	O
deterministic	O
,	O
i.e.	O
</s>
<s>
the	O
failure	O
probability	O
is	O
precisely	O
zero	O
,	O
Avalanche	B-Application
loosens	O
this	O
requirement	O
,	O
thus	O
enabling	O
quorum-based	B-General_Concept
protocols	O
to	O
estimate	O
global	O
network	O
state	O
with	O
errors	O
.	O
</s>
<s>
While	O
the	O
Snow	O
family	O
can	O
be	O
theoretically	O
generalized	O
to	O
all	O
classes	O
of	O
assumptions	O
that	O
quorum-based	B-General_Concept
protocols	O
have	O
previously	O
made	O
,	O
the	O
formalization	O
paper	O
analyzes	O
Avalanche	B-Application
under	O
an	O
asynchronous	O
network	O
in	O
the	O
Byzantine	B-Operating_System
setting	O
.	O
</s>
<s>
Processors	O
may	O
experience	O
arbitrary	O
failures	O
,	O
even	O
Byzantine	B-Operating_System
ones	O
.	O
</s>
<s>
(	O
That	O
is	O
,	O
Byzantine	B-Operating_System
failures	I-Operating_System
are	O
permissible	O
.	O
)	O
</s>
<s>
The	O
Snow	O
family	O
generalizes	O
the	O
typical	O
definitions	O
of	O
safety	O
and	O
liveness	O
encountered	O
in	O
quorum-based	B-General_Concept
protocols	O
.	O
</s>
<s>
For	O
Avalanche	B-Application
specifically	O
,	O
these	O
properties	O
are	O
:	O
</s>
<s>
Avalanche	B-Application
,	O
like	O
other	O
asynchronous	O
networks	O
,	O
is	O
not	O
guaranteed	O
to	O
terminate	O
and	O
thus	O
does	O
not	O
have	O
the	O
liveness	O
property	O
,	O
during	O
asynchrony	O
.	O
</s>
<s>
Like	O
Paxos	B-Operating_System
,	O
Avalanche	B-Application
's	O
goal	O
is	O
to	O
ensure	O
fault	B-General_Concept
tolerance	I-General_Concept
and	O
it	O
guarantees	O
safety	O
under	O
asynchrony	O
,	O
but	O
not	O
liveness	O
.	O
</s>
<s>
This	O
is	O
in	O
contrast	O
to	O
Nakamoto	O
consensus	B-Operating_System
,	O
which	O
guarantees	O
liveness	O
,	O
and	O
not	O
safety	O
under	O
asynchrony	O
.	O
</s>
