ICP parameter*      ==  ICP=icpServerList[:icpServerSpec[:connMap]]
     icpServerList  ==  icpServer[,icpServer]*
         icpServer  ==  icpHost[/icpType/proxyPort/icpPort]
     icpServerSpec  ==  icpOptions:proxyPort:icpPort
           connMap  ==  ProtoList:dstHostList:srcHostList
                    --  default: none
                    --  restriction: applicable to {HTTP,FTP}-DeleGate

If specified, and if "icp" is included in the CONNECT sequence, a HTTP-DeleGate will try to get a requested resource from specified ICP server. The meaning and default value of each field is as follows:

icpHost:

The host name or IP address of the ICP server [localhost]

icpType:

s	-- the ICP server is a "sibling" [default]
p	-- the ICP server is a "parent"
l	-- the ICP server is a "listener" which never respond
n	-- the ICP server is a navigation proxy
o	-- require HIT_OBJ response
H	-- the object server is a HTTP proxy [default]
D	-- the object server is a MASTER-DeleGate.
O	-- the object server is an origin server.

proxyPort:

The port number of the corresponding object server [8080].

icpPort:

The port number of ICP protocol [3130].

icpOptions:

timeout/N	-- period to wait response as an ICP client (in seconds)[2.0]
parent	-- mark the default type of icpServers as "parent"
listener	-- mark the default type of icpServers as "listener"
hitobj	-- enable HIT_OBJ for all icpServers by default
Origin	-- object servers are origin server
DeleGate	-- object servers are DeleGate

Example:

ICP=icphost
// This is the simplest usage which is the abbreviation of
// ICP="icphost/sH/8080/3130:timeout/2.0:8080:3130:*:*:*"


ICP="host0"
ICP="host0//8080/3130"
ICP="host0::8080:3130"
ICP="host1:timeout/1.0:::http,ftp:!*.my.domain:*.my.domain"
ICP="host1,host2/O/80/13130:timeout/2.0:8080:3130"