Need help designing tables for users/security/module access

[gummbeey]

(Please see attachments before reading)

Ok, so heres a typical application..

1) The application has multi-level modules and multi-level users.

2) A user can have access across different modules.
Ex: JOE ORANGE has access to 3 and 7.

3) A user has access to all modules (descendants) below a module that he has access to.
Ex: ANN BLUE has access to 6, therefore he has access to 9 and 10.

4) A parent user controls the child users.
Ex: BOB GREEN contols JOE ORANGE and KEN PURPLE.

5) A parent user can only assign up to his own access to his child users.
Ex: JOE ORANGE only has access access to 3 and 7, so he cannot give access 1, 2 nor 4 to his descendants.

6) OPTIONAL A parent user can control all his descendants skipping his immediate childs.
Ex: BOB GREEN can remove access 10 to ANN BLUE without affecting JOE ORANGE.

7) OPTIONAL A user can exist under a different branch, but not within his own branch
Ex: KEN PURPLE is under BOB GREEN. KEN PURPLE can also be under ANN BLUE, but not under SUE RED.

Can someone help me design some tables so I can fit this model?
Please consider the following:

1) Flexible
- Able to add/delete/edit modules and users

2) Data Integrity
- Ex: If JOE ORANGE loses access to 10, then all his descendants should not have access to 10.

3) Relatively Fast
- Checking access will be done quite often throughout the application.

4) Readability
- Simple structure for both the end-user and the programmer for quick reports and simple user interface.

5) High-Volume Data
- My example uses 10 modules and 6 users. Our real system could be using 10,000 modules and 2,000 users.

Here's what I've come up with so far.

[font=Courier New]TABLE: MODULE [/font]
[font=Courier New]Id		 Parent[/font]
[font=Courier New]---		 ------[/font]
[font=Courier New]1		 0[/font]
[font=Courier New]2		 1 [/font]
[font=Courier New]3		 1[/font]
[font=Courier New]4		 2[/font]
[font=Courier New]5		 3[/font]
[font=Courier New]6		 3[/font]
[font=Courier New]7		 4 [/font]
[font=Courier New]8		 5[/font]
[font=Courier New]9		 5[/font]
[font=Courier New]10		6[/font]
[font=Courier New][/font]
[font=Courier New]TABLE: USER [/font]
[font=Courier New]Name		 Parent		 Access?[/font]
[font=Courier New]----------- ----------- -------[/font]
[font=Courier New]BOB GREEN	 (NONE)[/font]
[font=Courier New]JOE ORANGE	 BOB GREEN[/font]
[font=Courier New]KEN PURPLE	 BOB GREEN[/font]
[font=Courier New]ANN BLUE	 JOE ORANGE[/font]
[font=Courier New]KIM YELLOW	 JOE ORANGE[/font]
[font=Courier New]SUE RED		 KEN PURPLE[/font]

Ugh!! this CODE tag doesnt work!! its not aligning my words