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ALPHA-VISION® HowTo: Access Protection
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Access Protection
SUMMARY
It is described how to set up Access Protection.
CONTENTS
- Overview
- The Alpha-Vision concept for Access Protection
- Preliminary work
- Access Protection of Pictures
- Access Protection of actions
- Example of setting up Access Protection
Overview
The access of pictures can be restricted.
Executing of actions can be restricted in relation to Access Rights and/or
Process Conditions.
While enquiring process conditions is deduced from technical necessity,
the Access Protection Structure must be defined. It has to be
determined which functions must be protected and who is entitled to
access what function.
The Alpha-Vision concept for Access Protection
In ALPHA-VISION® Access Protection is realized via Function Numbers.
- A Function Number correlates to a permission level.
- Function Numbers are pooled to User Profiles.
- User Profiles are assigned to Users.
An access or actions are allocated to Function Numbers; only users having
that number in their profile may execute that action or access something.
Via different grouping of Function Numbers in User Profiles any wanted
authorization structure can be set up.
Preliminary work
- Function Numbers have to be created.
- User Profiles have to be created.
- Users must be created.
See thereto:
AvET - User Administration
Access Protection of Pictures
Access authorization for pictures is defined via the pull-down menu
“Edit”, item “Information” of the editor.
A newly created picture is accessible for everybody by default; if the
access should be restricted it must be defined explicitly.
See field name: ‚Function No.’
Access Protection of actions
Access authorization for actions are defined via the pull-down menu
“Edit”, item 'Attributes Sequential...' Category
"Enable" in the Editor.
For actions access rights and/or preconditions may be defined.
Precondition and access right may be defined independently, if both are
defined there are AND gated.
If in runtime a defined condition is not met, the control element is
greyed – it is not operable.
Note:
A button and its label must be joined together by “Label Button” to get
the ‘greyed’ effect.
A button calling a restricted picture is not shown greyed.
Via Authorisation
If an action is to be carried out by authorized users
only, it must be locked by a 'Function No. (Control Access)' in the
category "Enable".
Only if the logged in user got that number in his profile he is
entitled to carry out that function.
Via Preconditions
If the execution of an action depends on a condition to be
fulfilled, it must be defined as an “Enable function” in the category
‘Enable'.
As “Enable function” you define a function that returns a value
different to “0” if the precondition is fulfilled.
Example of setting up Access Protection
The structure of access rights should be fairly clear when starting to
create a project.
It is suggested to create tables similar to that below.
Concept for Access Protection
The Access Control should be divided into 3 levels:
- Process control and standard operations - Level 1 (5 User)
- Critical Controls - Level 2 (2 User)
- Parameter change, system interference - Level 3 (1 User)
As a precondition to be fulfilled should be defined that pumps can only
be started if liquid is present.
User List with Profiles
From that demands we deduce the following users and profiles:
| User |
User Profile |
Functions |
| User_1 - 5 |
1 (Level 1) |
0 |
| Supervisor_1/2 |
10 (Level 2) |
0, 10 |
| Admin (Level 3) |
90 (Level 3) |
0, 10, 90 |
Technology Pictures
| Picture Name |
Access |
Restrictions in controlling |
| START |
Level 1 |
non |
| AAA001 |
Level 1 |
Button: Start Pump (Liquid ?) |
| : |
: |
: |
| : |
: |
: |
| AAA011 |
Level 1 |
Button: Fade Out Measuring Point (Fct. 10) |
| BBB001 |
Level 2 |
non |
| BBB002 |
Level 2 |
Calling Dialog Window "shut_down" (Fct. 90) |
| CCC001 |
Level 3 |
non |
Definitions in the pictures
- Picture: AAA001 to AAA010
The function "Obj_StsCmp(OilLevel_n,1)"
is defined as "Enable function"
in the Category ‘Enable’ of the button “Start Pump”.
(It is assumed that the Data Object “OilLevel_n” returns
status “1” if liquid is present.)
- Picture: AAA011
The “Function No. (Control Access)” in the category "Enable" of the
button “Fade Out Measuring Point” is set to “10”.
- Picture: BBB001
The “Fnctn No:” for “Access:” and “Browsing:” below ‘Information’ is
set to “10”.
- Picture: BBB002
The “Fnctn No:” for “Access:” and “Browsing:” below ‘Information’ is
set to “10”.
The “Function No. (Control Access)” in the category "Enable" of the
button for calling the Dialog Window "shut_down" is set to "90".
- Picture: CCC001
The “Fnctn No:” for “Access:” and “Browsing:” below ‘Information’ is
set to “90”.