<s>
ZMap	B-Protocol
is	O
a	O
free	B-License
and	I-License
open-source	I-License
security	B-General_Concept
scanner	I-General_Concept
that	O
was	O
developed	O
as	O
a	O
faster	O
alternative	O
to	O
Nmap	B-Language
.	O
</s>
<s>
ZMap	B-Protocol
was	O
designed	O
for	O
information	O
security	O
research	O
and	O
can	O
be	O
used	O
for	O
both	O
white	O
hat	O
and	O
black	O
hat	O
purposes	O
.	O
</s>
<s>
The	O
tool	O
is	O
able	O
to	O
discover	O
vulnerabilities	O
and	O
their	O
impact	O
,	O
and	O
detect	O
affected	O
IoT	B-Operating_System
devices	O
.	O
</s>
<s>
Using	O
one	O
gigabit	O
per	O
second	O
of	O
network	O
bandwidth	O
,	O
ZMap	B-Protocol
can	O
scan	O
the	O
entire	O
IPv4	B-Protocol
address	B-General_Concept
space	I-General_Concept
in	O
44	O
minutes	O
on	O
a	O
single	O
port	B-Protocol
.	O
</s>
<s>
With	O
a	O
ten	O
gigabit	O
connection	O
,	O
ZMap	B-Protocol
scan	O
can	O
complete	O
a	O
scan	O
in	O
under	O
five	O
minutes	O
.	O
</s>
<s>
ZMap	B-Protocol
iterates	O
on	O
techniques	O
utilized	O
by	O
its	O
predecessor	O
,	O
Nmap	B-Language
,	O
by	O
altering	O
the	O
scanning	O
method	O
in	O
a	O
few	O
key	O
areas	O
.	O
</s>
<s>
Nmap	B-Language
sends	O
out	O
individual	O
signals	O
to	O
each	O
IP	B-Protocol
address	I-Protocol
and	O
waits	O
for	O
a	O
reply	O
.	O
</s>
<s>
As	O
replies	O
return	O
,	O
Nmap	B-Language
compiles	O
them	O
into	O
a	O
database	O
to	O
keep	O
track	O
of	O
responses	O
,	O
a	O
process	O
that	O
slows	O
down	O
the	O
scanning	O
process	O
.	O
</s>
<s>
In	O
contrast	O
,	O
ZMap	B-Protocol
uses	O
cyclic	O
multiplicative	O
groups	O
,	O
which	O
allows	O
ZMap	B-Protocol
to	O
scan	O
the	O
same	O
space	O
roughly	O
1,300	O
times	O
faster	O
than	O
Nmap	B-Language
.	O
</s>
<s>
The	O
ZMap	B-Protocol
software	O
takes	O
every	O
number	O
from	O
1	O
to	O
232-1	O
and	O
creates	O
an	O
iterative	O
formula	O
that	O
ensures	O
that	O
each	O
of	O
the	O
possible	O
32-bit	O
numbers	O
is	O
visited	O
once	O
in	O
a	O
pseudorandom	B-Error_Name
order	O
.	O
</s>
<s>
Building	O
the	O
initial	O
list	O
of	O
numbers	O
for	O
every	O
IP	B-Protocol
address	I-Protocol
takes	O
upfront	O
time	O
,	O
but	O
it	O
is	O
a	O
fraction	O
of	O
what	O
is	O
required	O
to	O
aggregate	O
a	O
list	O
of	O
every	O
sent	O
and	O
received	O
probe	O
.	O
</s>
<s>
This	O
process	O
ensures	O
that	O
once	O
ZMap	B-Protocol
starts	O
sending	O
probes	O
out	O
to	O
different	O
IPs	O
,	O
an	O
accidental	O
denial	O
of	O
service	O
could	O
not	O
occur	O
because	O
an	O
abundance	O
of	O
transmissions	O
would	O
not	O
converge	O
on	O
one	O
subnet	B-Protocol
at	O
the	O
same	O
time	O
.	O
</s>
<s>
ZMap	B-Protocol
also	O
speeds	O
up	O
the	O
scanning	O
process	O
by	O
sending	O
a	O
probe	O
to	O
every	O
IP	B-Protocol
address	I-Protocol
only	O
once	O
by	O
default	O
,	O
whereas	O
Nmap	B-Language
resends	O
a	O
probe	O
when	O
it	O
detects	O
a	O
connection	O
delay	O
or	O
fails	O
to	O
get	O
a	O
reply	O
.	O
</s>
<s>
This	O
results	O
in	O
about	O
2%	O
of	O
IP	B-Protocol
addresses	I-Protocol
being	O
missed	O
during	O
a	O
typical	O
scan	O
,	O
but	O
when	O
processing	O
billions	O
of	O
IP	B-Protocol
address	I-Protocol
,	O
or	O
potential	O
IoT	B-Operating_System
devices	O
being	O
targeted	O
by	O
cyberattackers	O
,	O
2%	O
is	O
an	O
acceptable	O
tolerance	O
.	O
</s>
<s>
ZMap	B-Protocol
can	O
be	O
used	O
for	O
both	O
vulnerability	O
detection	O
and	O
exploitation	O
.	O
</s>
<s>
The	O
application	O
has	O
been	O
used	O
for	O
port	B-Protocol
443	I-Protocol
scans	O
to	O
estimate	O
power	O
outages	O
during	O
Hurricane	O
Sandy	O
in	O
2013	O
.	O
</s>
<s>
One	O
of	O
the	O
developers	O
of	O
ZMap	B-Protocol
,	O
Zakir	O
Durumeric	O
,	O
used	O
his	O
software	O
to	O
determine	O
a	O
computer	O
's	O
online	O
state	O
,	O
vulnerabilities	O
,	O
operating	B-General_Concept
system	I-General_Concept
,	O
and	O
services	B-Operating_System
.	O
</s>
<s>
ZMap	B-Protocol
has	O
also	O
been	O
used	O
to	O
detect	O
vulnerabilities	O
in	O
universal	B-Application
plug	I-Application
and	I-Application
play	I-Application
devices	O
and	O
search	O
for	O
weak	O
public	B-Application
keys	I-Application
in	O
HTTPS	B-Protocol
website	O
logs	O
.	O
</s>
