<s>
eDonkey2000	B-Protocol
(	O
nicknamed	O
"	O
ed2k	B-Protocol
"	O
)	O
was	O
a	O
peer-to-peer	O
file	O
sharing	O
application	O
developed	O
by	O
US	O
company	O
MetaMachine	O
(	O
Jed	O
McCaleb	O
and	O
Sam	O
Yagan	O
)	O
,	O
using	O
the	O
Multisource	O
File	O
Transfer	O
Protocol	O
.	O
</s>
<s>
It	O
supported	O
both	O
the	O
eDonkey2000	B-Protocol
network	O
and	O
the	O
Overnet	B-Protocol
network	O
.	O
</s>
<s>
Users	O
on	O
the	O
eDonkey2000	B-Protocol
network	O
predominantly	O
share	O
large	O
files	O
of	O
tens	O
or	O
hundreds	O
of	O
megabytes	O
,	O
such	O
as	O
CD	O
images	O
,	O
videos	O
,	O
games	O
,	O
and	O
software	O
programs	O
.	O
</s>
<s>
To	O
ease	O
file	O
searching	O
,	O
some	O
websites	O
list	O
the	O
checksums	B-Algorithm
of	O
sought-after	O
files	O
in	O
the	O
form	O
of	O
an	O
ed2k	B-Protocol
link	I-Protocol
.	O
</s>
<s>
MetaMachines	O
has	O
also	O
created	O
another	O
file-sharing	O
network	O
called	O
Overnet	B-Protocol
,	O
which	O
interoperates	O
with	O
the	O
eDonkey	O
network	O
,	O
but	O
without	O
the	O
use	O
of	O
servers	O
.	O
</s>
<s>
Most	O
eDonkey	O
clients	O
also	O
now	O
use	O
the	O
Overnet	B-Protocol
network	O
.	O
</s>
<s>
In	O
2004	O
,	O
MetaMachines	O
announced	O
it	O
would	O
stop	O
development	O
of	O
Overnet	B-Protocol
to	O
concentrate	O
on	O
eDonkey2000	B-Protocol
(	O
though	O
the	O
eDonkey2000	B-Protocol
client	O
now	O
includes	O
the	O
Overnet	B-Protocol
protocol	O
)	O
.	O
</s>
<s>
eDonkey2000	B-Protocol
was	O
created	O
by	O
Jed	O
McCaleb	O
,	O
cofounder	O
of	O
Stellar	B-Protocol
,	O
and	O
was	O
first	O
released	O
on	O
September	O
6	O
,	O
2000	O
.	O
</s>
<s>
On	O
September	O
16	O
,	O
2000	O
,	O
client	O
and	O
server	O
versions	O
were	O
available	O
for	O
Microsoft	B-Application
Windows	I-Application
and	O
Linux	B-Application
.	O
</s>
<s>
Compared	O
to	O
earlier	O
P2P	O
file-sharing	O
program	O
Napster	B-Application
,	O
eDonkey2000	B-Protocol
featured	O
"	O
swarming	O
"	O
downloads	O
,	O
meaning	O
that	O
clients	O
could	O
download	O
different	O
pieces	O
of	O
a	O
single	O
file	O
from	O
different	O
peers	O
,	O
effectively	O
utilizing	O
the	O
combined	O
bandwidth	O
of	O
all	O
of	O
the	O
peers	O
instead	O
of	O
being	O
limited	O
to	O
the	O
bandwidth	O
of	O
a	O
single	O
peer	O
.	O
</s>
<s>
At	O
first	O
,	O
servers	O
were	O
isolated	O
from	O
one	O
another	O
as	O
with	O
Napster	B-Application
,	O
but	O
later	O
versions	O
of	O
the	O
eDonkey2000	B-Protocol
server	O
software	O
enabled	O
servers	O
to	O
form	O
a	O
search	O
network	O
.	O
</s>
<s>
A	O
third	O
improvement	O
compared	O
to	O
Napster	B-Application
was	O
the	O
use	O
of	O
file	O
hashes	B-Error_Name
instead	O
of	O
simple	O
filenames	O
in	O
search	O
results	O
.	O
</s>
<s>
File	O
searches	O
initiated	O
by	O
the	O
user	O
were	O
keyword-based	O
and	O
matched	O
against	O
the	O
filename	O
list	O
stored	O
on	O
the	O
eDonkey2000	B-Protocol
server	O
,	O
but	O
the	O
server	O
returned	O
a	O
list	O
of	O
filenames	O
paired	O
with	O
the	O
hash	B-Error_Name
values	I-Error_Name
of	O
those	O
files	O
to	O
the	O
client	O
.	O
</s>
<s>
When	O
selecting	O
a	O
file	O
from	O
the	O
list	O
presented	O
to	O
the	O
user	O
,	O
the	O
client	O
would	O
actually	O
initiate	O
a	O
download	O
by	O
hash	B-Error_Name
value	I-Error_Name
.	O
</s>
<s>
This	O
meant	O
that	O
a	O
file	O
could	O
have	O
many	O
different	O
filenames	O
across	O
different	O
peers	O
,	O
but	O
would	O
be	O
considered	O
identical	O
for	O
purposes	O
of	O
downloading	O
if	O
its	O
hash	B-Error_Name
was	O
the	O
same	O
.	O
</s>
<s>
The	O
two-level	O
(	O
client	O
and	O
server	O
)	O
peer-to-peer	O
network	O
architecture	O
offered	O
a	O
balance	O
between	O
centralized	O
systems	O
like	O
Napster	B-Application
,	O
and	O
decentralized	O
systems	O
like	O
Gnutella	B-Protocol
.	O
</s>
<s>
Where	O
Napster	B-Application
ultimately	O
proved	O
to	O
be	O
vulnerable	O
was	O
its	O
centralized	O
server	O
cluster	O
,	O
which	O
was	O
a	O
stable	O
target	O
for	O
legal	O
action	O
.	O
</s>
<s>
Gnutella	B-Protocol
's	O
original	O
design	O
,	O
featuring	O
total	O
elimination	O
of	O
the	O
server	O
network	O
in	O
favor	O
of	O
purely	O
peer-to-peer	O
searching	O
,	O
quickly	O
proved	O
to	O
be	O
infeasible	O
due	O
to	O
massive	O
search	O
traffic	O
overhead	O
between	O
peers	O
.	O
</s>
<s>
Later	O
2nd-level	O
P2P	O
file	O
sharing	O
systems	O
use	O
a	O
similar	O
design	O
to	O
eDonkey2000	B-Protocol
(	O
downloading	O
files	O
in	O
pieces	O
by	O
hash	B-Error_Name
from	O
multiple	O
peers	O
simultaneously	O
)	O
but	O
innovate	O
in	O
the	O
design	O
of	O
the	O
server	O
network	O
,	O
such	O
as	O
in	O
the	O
case	O
of	O
BitTorrent	B-Protocol
,	O
which	O
separates	O
the	O
file	O
search	O
feature	O
(	O
"	O
torrent	B-Protocol
search	I-Protocol
"	O
)	O
from	O
the	O
download	O
peer	O
locating	O
feature	O
(	O
"	O
torrent	B-Protocol
tracker	O
"	O
)	O
.	O
</s>
<s>
The	O
latest	O
version	O
of	O
the	O
official	O
eDonkey2000	B-Protocol
client	O
included	O
a	O
plugin	O
that	O
allowed	O
BitTorrent	B-Protocol
files	O
to	O
be	O
downloaded	O
.	O
</s>
<s>
Once	O
a	O
torrent	B-Protocol
download	O
begins	O
the	O
search	O
facility	O
within	O
eDonkey	O
can	O
find	O
the	O
same	O
file	O
within	O
the	O
eDonkey/Overnet	O
network	O
and	O
synchronise	O
its	O
download	O
.	O
</s>
<s>
This	O
effectively	O
allowed	O
a	O
torrent	B-Protocol
to	O
be	O
used	O
as	O
another	O
source	O
for	O
the	O
download	O
,	O
vastly	O
increasing	O
speed	O
as	O
well	O
as	O
virtually	O
eliminating	O
problems	O
with	O
fakes	O
.	O
</s>
<s>
Torrents	B-Protocol
are	O
very	O
"	O
clean	O
"	O
in	O
terms	O
of	O
falsely	O
labelled	O
files	O
and	O
their	O
use	O
as	O
file	O
size	O
verifiers	O
in	O
addition	O
to	O
eDonkey2000	B-Protocol
's	O
own	O
user-based	O
fake	O
warning	O
system	O
has	O
vastly	O
improved	O
the	O
network	O
's	O
functionality	O
.	O
</s>
<s>
By	O
effectively	O
combining	O
the	O
range	O
of	O
the	O
existing	O
Overnet	B-Protocol
and	O
eDonkey	O
networks	O
with	O
the	O
lightning-fast	O
file	O
distribution	O
of	O
the	O
BitTorrent	B-Protocol
system	O
,	O
eDonkey2000	B-Protocol
was	O
following	O
a	O
growing	O
trend	O
amongst	O
peer-to-peer	O
programmes	O
of	O
integrating	O
downloads	O
from	O
multiple	O
networks	O
.	O
</s>
<s>
Nevertheless	O
,	O
the	O
eDonkey	O
network	O
is	O
still	O
available	O
through	O
other	O
clients	O
,	O
such	O
as	O
eMule	B-Protocol
or	O
aMule	B-Language
.	O
</s>
