Thank you John, This was my understanding too, after other experts have replied.
All the best, Eddie L. -----Original Message----- From: John Larmouth [mailto:[EMAIL PROTECTED] Sent: Friday, May 27, 2005 1:44 PM To: Eduard Lascu Cc: Asn1 Subject: Re: [ASN1] Does BER require the encoding of the type information? If you use IMPLICIT tagging, a context specific tag replaces the UNIVERSAL class tag, and it does not appear in the enocding. If you use EXPLICIT tagging, both tags appear in the encoding. John L Eduard Lascu wrote: > Hello everybody, > > Does anybody know whether BER would require the encoding of the type > information for every data field of a sequence? I know that if it uses the > UNIVERSAL class, the tags can tell what is the type that is encoded in the > VALUE field. However, if the sequence has some optional fields, than the > encoding should use CONTEXT SPECIFIC tags and the tags have different > meaning now (they must uniquely identify the fields of the structure). > Therefore the type information of the encoded fields is lost. > Is this a correct interpretation of the BER standard? > > Best regards and thanks for the help, > Eddie L. > > Eddie Lascu > Senior Software Developer, Associate > IBI Group > 230 Richmond St. W., 5th Floor > Toronto ON M5V 1V6 > Tel. (416) 596-1930 x312 > Fax. (416) 596-0644 > www.ibigroup.com > > > NOTE: This e-mail message and attachments may contain privileged and > confidential information. If you have received this message in error, > please immediately notify the sender and delete this e-mail message. > > "NOTE: Ce courriel peut contenir de l'information privil�gi�e et > confidentielle. Si vous avez re�u ce message par erreur, veuillez le > mentionner imm�diatement � l'exp�diteur et effacer ce courriel." > > _______________________________________________ > ASN1 mailing list > [email protected] > http://lists.asn1.org/mailman/listinfo/asn1 > > -- Prof John Larmouth Larmouth T&PDS Ltd (Training and Protocol Development Services Ltd) 1 Blueberry Road Bowdon [EMAIL PROTECTED] Cheshire WA14 3LS England Tel: +44 161 928 1605 Fax: +44 161 928 8069 _______________________________________________ ASN1 mailing list [email protected] http://lists.asn1.org/mailman/listinfo/asn1
