[Css-csts] EXECUTE-DIRECTIVE Possible redefinitions

[Yves.Doat at esa.int]

Dear all,

I know you are all back in your daily work and quite busy so I will do my 
best to be short. My question is at the end of the mail.

I started to look at the EXECUTE-DIRECTIVE trying to answer the RID we 
discussed last week,

RID references: NASA-JVP-15. NASA-JVP-16.

Our requirements:
Enure a procedure and/or a service using the operation to have the 
possibility to use the operation withour extension.
Reuse the AbstractType (proposed definition as follows):
-- This type is used by operations allowing the procedures
-- using them to two possibilities for the definition of the data:
-- 1. opaqueString: direct use. No extension required
-- 2. extendedData: definition of a complex type using a constructed 
syntax
AbstractChoice                  ::=     CHOICE
{       opaqueString            OCTET STRING
,       extendedData            EMBEDDED PDV
}
Link the the directive qualifier to the directive identifier.

Possible redefinitions
Option 1:
 Exec-Dir
        Pro?s:          - reuse AbstractChoice
                        - simple
                 - if dir-qual is not required we add a requirement to use 
an empty octet-string
        Con?s:  - mixture octet-string & extended is possible.
                - does not link a given dir-qual to a given dir-id: 
dedicated requirement in the text can solve that.
                        - in case dir-qualif is not required, it cannot be 
mapped to a NULL value but to an empty Octet String.
        ExecuteDirectiveInvocationOption1       ::=     SEQUENCE
        {       standardInvocationHeader        StandardInvocationHeader
        ,     directiveIdentifier               AbstractChoice
        ,       directiveQualifier              AbstractChoice  -- 
qualifier of the directive identifier
        ,       extensionParameter              Extended
        }

Option 2:
 Exec-Dir same as option 1 but with a different dir-qualif definition
        Pro?s:          - reuse AbstractChoice
                        - simple
                 - if dir-qual is not required we add a requirement to use 
an empty octet-string
        Con?s:  - mixture octet-string & extended is possible.
                - does not link a given dir-qual to a given dir-id: 
dedicated requirement in the text can solve that.
        ExecuteDirectiveInvocationOption1       ::=     SEQUENCE
        {       standardInvocationHeader        StandardInvocationHeader
        ,     directiveIdentifier               AbstractChoice
        ,       directiveQualifier              CHOIDE -- qualifier of the 
directive identifier
                {               octetString             [0] OCTET STRING
                ,               null                    [1] NULL
                ,               extended                [2] EMBEDDED PDV
                }
        ,       extensionParameter              Extended
        }


Option 3:
        Pro?s:          - does not allows octet-string & extended mixture
        Con?s:          - more complex structure (but still workable)
                - AbstractChoice not reused
                - does not link a given dir-qual to a given dir-id. 
dedicated requirement in the text can solve that.
        ExecuteDirectiveInvocationOption2       ::=     SEQUENCE
        {       standardInvocationHeader        StandardInvocationHeader
        ,       directiveIdentification         CHOICE
                (       octetString                     [0]     SEQUENCE
                        {       directiveIdentifier             OCTET 
STRING
                        ,       directiveQualifier              CHOICE
                                {       selected [0]    OCTET STRING
                                ,       unused                  [1] NULL
                                }
                        }
        ,               Extended                        [1]     SEQUENCE
                        {       directiveIdentifier             EMBEDDED 
PDV
                        ,       directiveQualifier              CHOICE
                                {       selected [0]    EMBEDDED PDV
                                ,       unused                  [1] NULL
                                }
                        }
        ,       extensionParameter              Extended
        }

Notes:
- None of the options ensure a proper link between the identifier and he 
qualifier. We should be able to cover the link by appropriate requirements 
in the text
- Option 1 is the simplest but may require more requirements for a proper 
usage.

Could you please let me know from your opinion which option answers the 
best our discussions from last week.
Option 1?
Option 2?
Option 3?
New option?

Best regards
Yves
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