On Mon, 6 Oct 2003, Paul Thorpe wrote: > Hi Ramaswamy, > > The only reason I think of for doing this is if you want to to control the > position in BER at which "age" is encoded (before middle-name in the > first case, and after middle-name in the seccond case). Note that PER > will put "age" at the end in both cases.
Correct. The ability to add extension additions in the middle of a SEQUENCE was introduced into ASN.1 to meet the needs of the X.500 (Directory) standards. Directory in some cases requires extension additions to occur other than at the end of the SEQUENCE. Bancroft > ---------------------------------------------------------------------------- > Paul E. Thorpe Toll Free : 1-888-OSS-ASN1 > OSS Nokalva International: 1-732-302-0750 > Email: [EMAIL PROTECTED] Tech Support : 1-732-302-9669 > http://www.oss.com Fax : 1-732-302-0023 > > On Mon, 6 Oct 2003, Ramaswamy wrote: > > > Hi, > > I have the following query regarding the significance of the 2nd extension > > marker permitted in a SEQUENCE / SET type. > > > > What is the difference in interpretation / significance b/w the following 2 > > notations of extended SEQUENCE across 2 different versions on the SEQUENCE. To be > > more precise, what is the advantage / implication of using the 2nd extension > > marker notation compared to the one with single-extension marker. > > > > -------------------------------------------------------------------------------- > > > > Details ::= -- Version1 > > SEQUENCE > > { > > first-name PrintableString, > > last-name PrintableString, > > ..., > > ..., > > middle-name PrintableString > > } > > > > =================================================================== > > Details ::= -- Version2 > > SEQUENCE > > { > > first-name PrintableString, > > last-name PrintableString, > > ..., > > age INTEGER(0..999) > > ..., > > middle-name PrintableString > > } > > > > -------------------------------------------------------------------------------- > > > > > > > > -------------------------------------------------------------------------------- > > > > Details ::= -- Version1 > > SEQUENCE > > { > > first-name PrintableString, > > last-name PrintableString, > > middle-name PrintableString, > > ... > > } > > > > =================================================================== > > Details ::= -- Version2 > > SEQUENCE > > { > > first-name PrintableString, > > last-name PrintableString, > > middle-name PrintableString, > > ..., > > age INTEGER(0..999) > > } > > > > -------------------------------------------------------------------------------- > > > > > > Thanking you. > > > > Yours Sincerely > > Ramaswamy > > > >
