<s>
CGI:IRC	B-Protocol
is	O
a	O
CGI	B-Language
program	O
written	O
in	O
Perl	B-Language
that	O
allows	O
access	O
to	O
IRC	B-Protocol
via	O
a	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
It	O
is	O
designed	O
to	O
be	O
flexible	O
and	O
has	O
many	O
uses	O
such	O
as	O
an	O
IRC	B-Protocol
gateway	O
for	O
an	O
IRC	B-Protocol
network	I-Protocol
,	O
a	O
chat-room	O
for	O
a	O
website	O
or	O
to	O
access	O
IRC	B-Protocol
when	O
stuck	O
behind	O
a	O
restrictive	O
firewall	B-Application
.	O
</s>
<s>
CGI:IRC	B-Protocol
will	O
work	O
in	O
most	O
browsers	B-Application
,	O
including	O
text	O
based	O
browsers	B-Application
such	O
as	O
Links	B-Application
.	O
</s>
<s>
To	O
make	O
full	O
use	O
of	O
most	O
of	O
the	O
available	O
features	O
,	O
a	O
newer	O
version	O
is	O
essential	O
;	O
older	O
browsers	B-Application
will	O
work	O
,	O
but	O
CGI:IRC	B-Protocol
will	O
use	O
a	O
single	O
windowed	O
interface	O
instead	O
and	O
the	O
names	O
list	O
will	O
not	O
update	O
as	O
quickly	O
.	O
</s>
<s>
With	O
a	O
modern	O
browser	B-Application
(	O
with	O
JavaScript	B-Language
and	O
DHTML	B-General_Concept
enabled	O
)	O
,	O
CGI:IRC	B-Protocol
will	O
present	O
a	O
tabbed	O
interface	O
similar	O
to	O
GUI	O
IRC	B-Protocol
clients	O
.	O
</s>
<s>
Some	O
common	O
IRC	B-Protocol
client	O
features	O
are	O
unavailable	O
,	O
such	O
as	O
scripting	O
,	O
DCC	O
chat	O
,	O
and	O
file	O
transfers	O
,	O
due	O
to	O
the	O
webserver-based	O
nature	O
of	O
CGI:IRC	B-Protocol
.	O
</s>
<s>
CGI:IRC	B-Protocol
is	O
used	O
by	O
many	O
IRC	B-Protocol
networks	I-Protocol
to	O
provide	O
a	O
way	O
for	O
users	O
to	O
chat	O
on	O
their	O
network	O
from	O
within	O
their	O
web	B-Application
browser	I-Application
.	O
</s>
<s>
Due	O
to	O
the	O
nature	O
of	O
CGI:IRC	B-Protocol
,	O
users	O
are	O
unable	O
to	O
use	O
DCC	O
.	O
</s>
<s>
What	O
was	O
a	O
seemingly	O
inconsequential	O
implementation	O
of	O
the	O
IRC	B-Protocol
protocol	O
is	O
increasingly	O
being	O
seen	O
as	O
a	O
means	O
to	O
evade	O
bans	O
in	O
IRC	B-Protocol
chat	I-Protocol
rooms	O
.	O
</s>
<s>
Several	O
IRC	B-Protocol
servers	O
have	O
,	O
as	O
a	O
consequence	O
,	O
developed	O
an	O
intolerance	O
for	O
CGI	B-Language
connections	O
.	O
</s>
<s>
Compounding	O
this	O
development	O
is	O
the	O
fact	O
that	O
there	O
does	O
not	O
exist	O
a	O
means	O
to	O
effectively	O
distinguish	O
between	O
a	O
CGI	B-Language
connection	O
and	O
a	O
real	O
IRC	B-Protocol
connection	O
.	O
</s>
<s>
Some	O
IRC	B-Protocol
servers	O
may	O
display	O
the	O
true	O
hostname	O
of	O
the	O
connecting	O
client	O
,	O
most	O
will	O
only	O
show	O
the	O
hostname	O
of	O
the	O
CGI:IRC	B-Protocol
proxy	O
.	O
</s>
<s>
A	O
simple	O
perl	B-Language
script	O
to	O
decode	O
the	O
IP	O
is	O
included	O
with	O
CGI:IRC	B-Protocol
.	O
</s>
<s>
Depending	O
on	O
how	O
CGI:IRC	B-Protocol
is	O
configured	O
,	O
it	O
may	O
also	O
return	O
the	O
users	O
true	O
IP	O
address	O
(	O
in	O
addition	O
to	O
the	O
HTTP	O
headers	O
)	O
in	O
response	O
to	O
a	O
CTCP	O
USERINFO	O
request	O
.	O
</s>
<s>
Just	O
like	O
other	O
open	O
proxies	O
,	O
open	O
installations	O
of	O
CGI:IRC	B-Protocol
,	O
which	O
do	O
not	O
restrict	O
the	O
server	O
used	O
,	O
can	O
also	O
be	O
abused	O
.	O
</s>
<s>
Usually	O
CGI:IRC	B-Protocol
is	O
abused	O
to	O
create	O
many	O
clones	O
,	O
which	O
are	O
used	O
to	O
flood	O
an	O
IRC	B-Protocol
network	I-Protocol
or	O
a	O
particular	O
user	O
.	O
</s>
<s>
In	O
response	O
,	O
many	O
networks	O
have	O
started	O
to	O
ban	O
CGI:IRC	B-Protocol
clients	O
except	O
those	O
which	O
originate	O
from	O
their	O
own	O
CGI:IRC	B-Protocol
proxy	O
(	O
if	O
they	O
have	O
one	O
)	O
.	O
</s>
<s>
CGI:IRC	B-Protocol
runs	O
on	O
a	O
webserver	B-Application
such	O
as	O
Apache	B-Application
configured	O
to	O
run	O
Perl	B-Language
,	O
and	O
uses	O
Unix	B-Application
domain	O
sockets	O
.	O
</s>
<s>
It	O
uses	O
a	O
special	O
HTTP	B-General_Concept
streaming	I-General_Concept
connection	O
while	O
communicating	O
with	O
the	O
user	O
's	O
web	B-Application
browser	I-Application
;	O
this	O
reduces	O
network	O
usage	O
because	O
the	O
user	O
's	O
webpage	O
is	O
not	O
continually	O
being	O
redrawn	O
.	O
</s>
<s>
Early	O
versions	O
of	O
some	O
web	B-Application
browsers	I-Application
such	O
as	O
Apple	B-Application
Safari	I-Application
had	O
problems	O
with	O
streaming	O
connections	O
.	O
</s>
<s>
CGI:IRC	B-Protocol
can	O
be	O
configured	O
to	O
allow	O
access	O
to	O
any	O
server	O
and	O
channel	O
,	O
or	O
restricted	O
to	O
single	O
instances	O
.	O
</s>
<s>
One	O
limitation	O
of	O
CGI:IRC	B-Protocol
with	O
respect	O
to	O
some	O
IRC	B-Protocol
servers	O
is	O
"	O
Because	O
CGI:IRC	B-Protocol
acts	O
as	O
a	O
client	O
,	O
connections	O
from	O
it	O
appear	O
to	O
be	O
coming	O
from	O
the	O
web	B-Application
server	I-Application
's	O
address	O
.	O
</s>
<s>
This	O
allows	O
it	O
to	O
get	O
past	O
firewalls	B-Application
,	O
but	O
if	O
several	O
clients	O
are	O
connecting	O
from	O
the	O
same	O
address	O
,	O
some	O
IRC	B-Protocol
servers	O
will	O
refuse	O
to	O
accept	O
additional	O
connections	O
beyond	O
a	O
certain	O
limit.	O
"	O
</s>
