<s>
A	O
CCSO	O
name-server	O
or	O
Ph	B-Protocol
protocol	I-Protocol
was	O
an	O
early	O
form	O
of	O
database	O
search	O
on	O
the	O
Internet	O
.	O
</s>
<s>
Today	O
this	O
service	O
has	O
been	O
largely	O
replaced	O
by	O
LDAP	B-Protocol
.	O
</s>
<s>
The	O
name-server	O
directories	O
were	O
frequently	O
organized	O
in	O
Gopher	B-Protocol
hierarchies	O
.	O
</s>
<s>
The	O
Ph	B-Protocol
protocol	I-Protocol
was	O
formally	O
defined	O
by	O
in	O
September	O
1998	O
.	O
</s>
<s>
Ph	O
server	O
communication	O
takes	O
place	O
on	O
TCP	B-Protocol
port	O
105	O
.	O
</s>
<s>
As	O
distributed	O
,	O
the	O
nameserver	O
was	O
backed	O
by	O
a	O
flat	B-Application
file	I-Application
database	I-Application
.	O
</s>
<s>
In	O
the	O
early	O
1990s	O
,	O
Indiana	O
University	O
software	O
developer	O
Larry	O
Hughes	O
implemented	O
a	O
version	O
of	O
Qi	O
(	O
called	O
"	O
Phd	O
"	O
)	O
that	O
was	O
written	O
in	O
Perl	B-Language
and	O
backed	O
by	O
a	O
relational	B-Application
database	I-Application
.	O
</s>
<s>
That	O
code	O
was	O
distributed	O
under	O
an	O
open-source	O
license	O
for	O
several	O
years	O
prior	O
to	O
the	O
university	O
's	O
transition	O
to	O
LDAP	B-Protocol
.	O
</s>
