Hi,
I had some break...
So, in your example the encoding of mySEQUENCE_1 and mySEQUENCE_2 will be the same.
This is not the case with myCHOICE_1 and myCHOICE_2. myCHOICE_1 will be skipped by
automatic tagging but alternatives of myCHOICE_2 will be automatically tagged as (not
seen of course, just "virtually" within the tool):
firstAlternative [0] FirstAlternative,
secondAlternative [1] SecondAlternative
So, when encoding both types will be encoded by a choice index of one bit. But in case
of myCHOICE_1 "0" will identify secondAlternative, because this has a smaller tag and
in case of myCHOICE_2 "0" will pinpoint firstAlternative, because this has a smaller
tag. And vice versa with the choice index "1". So, in your example removing
hand-written taggs in myCHOICE_1 will spoile the encoding.
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: Parichaya_Shrivastava
>[mailto:[EMAIL PROTECTED]]
>Sent: Wednesday, November 21, 2001 11:38 AM
>To: [EMAIL PROTECTED]
>Subject: RE: [ASN.1] AUTOMATIC Tagging and Unaligned-PER
>
>
>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]]
>> >
>
