REMITTABLE parameter == REMITTABLE=ProtoList
                    --  default: REMITTABLE="*" for generalist
                    --  default: REMITTABLE="." for specialist

Only protocols (to the server) listed in ProtoList will be permitted by this DeleGate.
For generalist (a DeleGate with SERVER="delegate" parameter) any protocols are permitted by default. For specialist, only the protocol specified in the SERVER parameter (which can be represented by ".") is permitted by default.

If a protocol name is followed by "/portNumList", only ports listed in the PortList is permitted. A PortList can be followed by "/methodList" which restricts available methods in the protocol. A pseudo method "readonly" is used to prohibit methods for modification. For example, REMITTABLE="ftp//readonly" make a FTP-DeleGate be "read only" which inhibits uploading to FTP servers.

Protocol Specific Default:

generalist-DeleGate

REMITTABLE="*" -- any protocol is remittable

HTTP-DeleGate

REMITTABLE="http,https/{80,443},gopher,ftp,wais,cgi,ssi" -- usual protocols expected to be relayed by HTTP-proxies

Telnet-DeleGate

REMITTABLE="telnet/23" -- restricted to be accessible only toward standard Telnet port (23). This restriction can be disarmed by specifying like REMITTABLE="telnet".

Exception:

When the current destination server is determined by a MOUNT parameter like MOUNT="Path1 Proto://Server/Path2", the protocol Proto is automatically allowed as a destination protocol with Server, regardless of REMITTABLE restriction.

If the first member of a list is "+", it means the default list of permitted protocols. For example, REMITTABLE="+,-https/80,-wais,file" with SERVER=http means REMITTABLE="http,https/443,gopher,ftp,file".
Note that "https" implies that non-HTTPS protocol on the SSLtunnel may be detected and rejected. If arbitrary protocol is to be relayed on the SSLtunnel, specify "ssltunnel" instead of "https" like REMITTABLE="+,ssltunnel".