Hi Krishna,
It will not affect Unaligned or for that matter Aligned PER in any way.
So the encoding for MyCHOICE_1 and MyCHOICE_2 will be same. 
Same will be true for MySEQUENCE_1 and MySEQUENCE_2.

Regards,
Parichaya (It was a nice lunch ;-)

> -----Original Message-----
> From: Krishna Reddy Gaddam [SMTP:[EMAIL PROTECTED]]
> Sent: Wednesday, November 21, 2001 1:04 PM
> To:   '[EMAIL PROTECTED]'; '[EMAIL PROTECTED]'; '[EMAIL PROTECTED]'
> Subject:      RE: [ASN.1] AUTOMATIC Tagging and Unaligned-PER
> 
> Hi Bancroft Scott and Gy�rgy
> 
> Thank you for your help.
> 
> I have the following specific question.
> 
> Please consider the following definitions.
> The encoding rule is ASN.1 PER (unaligned).
> 
> ------------------------------------------------------------------------
> Class-definitions DEFINITIONS AUTOMATIC TAGS ::=
> BEGIN
> 
> myCHOICE_1 ::= CHOICE {    
>       firstAlternative        [9]        FirstAlternative,
>       secondAlternative       [8]        SecondAlternative
> }
> 
> 
> mySEQUENCE_1 ::= SEQUENCE {    
>       firstField      [9]        FirstField,
>       secondField     [8]        SecondField
> }
> 
> myCHOICE_2 ::= CHOICE {    
>       firstAlternative          FirstAlternative,
>       secondAlternative      SecondAlternative
> }
> 
> mySEQUENCE_2 ::= SEQUENCE {    
>       firstField         FirstField,
>       secondField        SecondField
> }
> 
> END
> ------------------------------------------------------------------------
> 
> MyCHOICE_2 would be encoded as follows.
> 
>       for firstAlternative:           <0 i.e. prefix>  <encoding of the
> firstAlternative>
>       for secondAlternative:  <1 i.e. prefix>  <encoding of the
> secondAlternative >
> 
> MySEQUENCE_2 would be encoded as follows.
> 
>       <encoding of the firstField > <encoding of the secondField >
> 
> Questions:
> ----------
> 
>       Will the specification of tags (9 and 8) in myCHOICE_1 effect the
> prefix value of FirstAlternative and SecondAlternative?
>       If yes then how will the encoding of myCHOICE_1 be? 
>       And will IMPLICIT or EXPLICIT tagging have different effects on
> encoding of myCHOICE_1?
> 
>       Will the specification of tags (9 and 8) in mySEQUENCE_1 effect the
> encoding of mySEQUENCE_1?
> 
> Please provide us with pointers (Books/References), if any.
> 
> 
> Thanks and Regards
> Krishna
> 
> 
> -----Original Message-----
> From: Gyorgy Rethy (ETH) [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, November 20, 2001 4:10 PM
> To: '[EMAIL PROTECTED]'
> Subject: RE: [ASN.1] AUTOMATIC Tagging and Unaligned-PER
> 
> 
> Hi,
> 
> No, not at all. I would say quite the opposit. Automatic tagging works
> only
> on types, which does not contain "hand-written" tags. If textual taggs are
> removed from a module, automatic tagging may allocate a different tag to
> components of SEQUENCEs, SETs  or alternatives of CHOICEs as the textual
> tag
> was. This may cause a different re-ordering of SET components or CHOICE
> alternatives as it would be with textual taggs and spoile encoding.
> 
> This is a different issue, that there may be modules not using automatic
> tagging but tagged quite the same way manually as the automatic mechanism
> would do.
> 
> By the way it is unimportant from this point of view if the encoding is
> aligned or unaligned.
> 
> Best Regards, Gy�rgy
> 
> ============================================
> dr. Gy�rgy R�THY
> Ericsson Communications Systems Hungary Lim.
> Conformance Center
> tel.: +36 1 437-7006; fax: +36 1 437-7767
> mobile: +36 30 297-7862
> e-mail: [EMAIL PROTECTED]
> web: http://www.r.eth.ericsson.se/~ethgry
> ============================================
> 
> 
> >-----Original Message-----
> >From: Krishna Reddy Gaddam [mailto:[EMAIL PROTECTED]]
> >Sent: Monday, November 19, 2001 9:58 AM
> >To: [EMAIL PROTECTED]
> >Cc: '[EMAIL PROTECTED]'
> >Subject: [ASN.1] AUTOMATIC Tagging and Unaligned-PER
> >
> >
> >Hi All
> >
> >Is it correct to say :
> >--------------------
> >If an ASN.1 module header says AUTOMATIC TAGS, 
> >the Unaligned-PER encoder need not bother to look into the any 
> >of the TAGS
> >in the whole module.
> >
> >Other way of saying :
> >---------------------
> >Is the module is just equivalent to all the TAGS removed from 
> >the module ?
> >
> >
> >Please clarify.
> >
> >Thanks in advance.
> >
> >Regards
> >Krishna [mailto:[EMAIL PROTECTED]]
> >

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