<s>
chrony	B-Application
is	O
an	O
implementation	O
of	O
the	O
Network	B-Protocol
Time	I-Protocol
Protocol	I-Protocol
(	O
NTP	O
)	O
.	O
</s>
<s>
It	O
's	O
an	O
alternative	O
to	O
ntpd	B-Protocol
,	O
which	O
is	O
a	O
reference	O
implementation	O
of	O
NTP	O
.	O
</s>
<s>
It	O
runs	O
on	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
(	O
including	O
Linux	B-Application
and	O
macOS	B-Application
)	O
and	O
is	O
released	O
under	O
the	O
GNU	B-License
GPL	I-License
v2	I-License
.	O
</s>
<s>
It	O
's	O
the	O
default	O
NTP	O
client	B-Protocol
and	O
server	B-Application
in	O
Red	O
Hat	O
Enterprise	O
Linux	B-Application
8	O
and	O
SUSE	O
Linux	B-Application
Enterprise	B-Application
Server	I-Application
15	O
,	O
and	O
available	O
in	O
many	O
Linux	B-Application
distributions	I-Application
.	O
</s>
<s>
Support	O
for	O
Network	B-Protocol
Time	I-Protocol
Security	I-Protocol
(	O
NTS	O
)	O
was	O
added	O
on	O
version	O
4.0	O
.	O
</s>
<s>
In	O
contrast	O
to	O
NTPsec	O
,	O
which	O
is	O
a	O
security-focused	O
fork	O
of	O
ntpd	B-Protocol
,	O
chrony	B-Application
was	O
implemented	O
from	O
scratch	O
.	O
</s>
<s>
It	O
was	O
designed	O
to	O
synchronize	O
time	O
even	O
in	O
difficult	O
conditions	O
such	O
as	O
intermittent	O
network	O
connections	O
(	O
such	O
as	O
laptops	B-Device
)	O
and	O
congested	O
networks	O
.	O
</s>
<s>
Some	O
improvements	O
in	O
this	O
regard	O
(	O
compared	O
to	O
reference	O
ntpd	B-Protocol
)	O
include	O
that	O
it	O
never	O
steps	O
(	O
abruptly	O
adjusts	O
)	O
time	O
outside	O
of	O
startup	O
,	O
can	O
correct	O
for	O
asymmetric	O
network	O
jitters	O
,	O
and	O
can	O
use	O
larger	O
clock	O
rate	O
adjustments	O
on	O
Linux	B-Application
to	O
deal	O
with	O
a	O
broken	O
clock	O
.	O
</s>
<s>
packet	O
times	O
on	O
the	O
network	O
adapter	O
)	O
,	O
improving	O
accuracy	O
of	O
time	B-Protocol
synchronization	I-Protocol
between	O
machines	O
on	O
a	O
LAN	B-General_Concept
to	O
the	O
order	O
of	O
70	O
nanoseconds	O
(	O
from	O
asymmetry	O
)	O
,	O
comparable	O
to	O
Precision	B-Protocol
Time	I-Protocol
Protocol	I-Protocol
.	O
</s>
<s>
for	O
GNSS	O
)	O
,	O
unlike	O
ntpd	B-Protocol
which	O
has	O
many	O
built-in	O
drivers	O
.	O
</s>
