<s>
Quagga	B-Protocol
is	O
a	O
network	B-Protocol
routing	I-Protocol
software	B-Application
suite	I-Application
providing	O
implementations	O
of	O
Open	B-Protocol
Shortest	I-Protocol
Path	I-Protocol
First	I-Protocol
(	O
OSPF	B-Protocol
)	O
,	O
Routing	B-Protocol
Information	I-Protocol
Protocol	I-Protocol
(	O
RIP	O
)	O
,	O
Border	B-Protocol
Gateway	I-Protocol
Protocol	I-Protocol
(	O
BGP	B-Protocol
)	O
and	O
IS-IS	B-Protocol
for	O
Unix-like	B-Operating_System
platforms	O
,	O
particularly	O
Linux	B-Application
,	O
Solaris	B-Application
,	O
FreeBSD	B-Operating_System
and	O
NetBSD	B-Device
.	O
</s>
<s>
Quagga	B-Protocol
is	O
distributed	O
under	O
the	O
terms	O
of	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
(	O
GPL	B-License
)	O
.	O
</s>
<s>
In	O
April	O
2017	O
,	O
FRRouting	B-Protocol
forked	O
from	O
Quagga	B-Protocol
aiming	O
for	O
a	O
more	O
open	O
and	O
faster	O
development	O
.	O
</s>
<s>
The	O
project	O
takes	O
its	O
name	O
from	O
the	O
quagga	B-Protocol
,	O
an	O
extinct	O
sub-species	O
of	O
the	O
African	O
zebra	B-Device
.	O
</s>
<s>
Quagga	B-Protocol
is	O
a	O
fork	O
of	O
the	O
GNU	B-Application
Zebra	I-Application
project	O
which	O
was	O
developed	O
by	O
Kunihiro	O
Ishiguro	O
and	O
which	O
was	O
discontinued	O
in	O
2005	O
.	O
</s>
<s>
The	O
Quagga	B-Protocol
tree	O
aims	O
to	O
build	O
a	O
more	O
involved	O
community	O
for	O
Quagga	B-Protocol
than	O
the	O
centralized	O
development-model	O
which	O
GNU	B-Application
Zebra	I-Application
followed	O
.	O
</s>
<s>
The	O
Quagga	B-Protocol
architecture	O
consists	O
of	O
a	O
core	O
daemon	O
(	O
zebra	B-Device
)	O
which	O
is	O
an	O
abstraction	B-Architecture
layer	I-Architecture
to	O
the	O
underlying	O
Unix	O
kernel	O
and	O
presents	O
the	O
Zserv	O
API	O
over	O
a	O
Unix-domain	O
socket	O
or	O
TCP	O
socket	O
to	O
Quagga	B-Protocol
clients	O
.	O
</s>
<s>
The	O
Zserv	O
clients	O
typically	O
implement	O
a	O
routing	B-Protocol
protocol	O
and	O
communicate	O
routing	B-Protocol
updates	O
to	O
the	O
zebra	B-Device
daemon	O
.	O
</s>
<s>
ripd	O
,	O
implementing	O
Routing	B-Protocol
Information	I-Protocol
Protocol	I-Protocol
(	O
RIP	O
)	O
version	O
1	O
and	O
2	O
;	O
</s>
<s>
Additionally	O
,	O
the	O
Quagga	B-Protocol
architecture	O
has	O
a	O
rich	O
development	O
library	O
to	O
facilitate	O
the	O
implementation	O
of	O
protocol	O
and	O
client	O
software	O
with	O
consistent	O
configuration	O
and	O
administrative	O
behavior	O
.	O
</s>
<s>
Google	O
has	O
contributed	O
to	O
improvements	O
to	O
the	O
IS-IS	B-Protocol
protocol	O
and	O
added	O
BGP	B-Protocol
multipath	O
support	O
.	O
</s>
