REFEREE Demo Instruction Page
How it works
- You fill out a HTML form that specifies your desired configuration, and
submit to my web server (running Jigsaw).
- The server invokes REFEREE with your attributes, and returns an answer in
the form of a tri-value and a statement-list. (Please see
REFEREE-1.4d Specification
for detail information).
- Your browser displays the output.
I will describe each step in detail.
Step 1: Filling Out the Form
The form looks like the following:
- Action: is the verb that identifies the policy. It is ignored
for this particular demo, because we supply only one policy to REFEREE
instead of a set of policies.
- URL: is the target URL we are operating on.
- Policy: is the policy written in Profiles-0.92 language which
will be interpreted by the Profiles-0.92 interpreter in server's REFEREE
environment.
- PICS Labels: is a place to specify the output of the
"load-label" invocation. In this way we are able to control what labels
we get back from the label bureaus.
- Submit Button: click here when you are ready to submit the form
for evaluation.
Step 2: Server Invokes REFEREE
The server parses your form and sets up REFEREE environment and
Profiles-0.92 interpreter appropriately. The interpreter runs your policy
against the PICS labels you supply, and returns a tri-value and a
statement-list as specified in the REFEREE document.
Step 3: Browser Displays the Output
A sample output is as followed:
he answer is as followed:
(
( Tri-Value "TRUE" )
( Statement List
(
(
( "Profiles" )
( "allow" "http://www.w3.org/" ) ) ) ) )
A trace is as followed:
eval:
( allow URL "http://www.w3.org/" )
result:
(
( Tri-Value "TRUE" )
( Statement List
(
(
( "Profiles" )
( "allow" "http://www.w3.org/" ) ) ) ) )
The output has two parts: an answer and a trace of the evaluation.
The answer consists of two parts: a 'Tri-Value' and a 'Statement-List'.
The 'Tri-Value' is the output of the policy evaluation and can return only
"TRUE", "FALSE", or "UNKNOWN". The 'Statement-List' is a set of statements
that supplement the tri-value. Each statement has two elements;
the first element converys the context (speaker) of the statment, and
the second element provides the content of the statement.
That is all. Enjoy the demo!
Comments to Yang-hua Chu
Created 27 October 1996 by Yang-hua Chu
Last updated 28 October 1996 by Yang-hua Chu