<s>
The	O
Internet	B-Protocol
Cache	I-Protocol
Protocol	I-Protocol
(	O
ICP	O
)	O
is	O
a	O
UDP-based	O
protocol	O
used	O
for	O
coordinating	O
web	B-Protocol
caches	I-Protocol
.	O
</s>
<s>
The	O
ICP	O
protocol	O
is	O
described	O
in	O
RFC	O
2186	O
,	O
its	O
application	O
to	O
hierarchical	O
web	B-Protocol
caching	I-Protocol
in	O
RFC	O
2187	O
.	O
</s>
<s>
HTCP	B-Protocol
,	O
designed	O
as	O
a	O
successor	O
to	O
ICP	O
,	O
attempts	O
to	O
handle	O
various	O
problems	O
found	O
in	O
ICP	O
deployments	O
.	O
</s>
