Thanks for the answers...
My second question was "How can I tell to the decoder that a structure must
be encoded with indefinite lenght and that another must be encoded with
definite lenght within the same input file? Is there any standard identifier
in the ASN.1 definition of the structure to use?".
My question was about the ASN1 syntax to say that a structure must be
encoded with indefinite lenght.
Thanks,
Roberto

-----Messaggio originale-----
Da: Bancroft Scott [mailto:[EMAIL PROTECTED]]
Inviato: mercoled� 11 settembre 2002 14.33
A: '[EMAIL PROTECTED]'
Oggetto: Re: [ASN.1] Abount definite and indefinite lenght encoding


On Wed, 11 Sep 2002, Pino Roberto wrote:

> Hi,
> I would like to know if it's possible with ASN.1, use different lenght
> encodings for structure in the same file.
> For example, is possible encoding a structure with indefinite lenght
> encoding and another (may be a substructure of the first one) with
definite
> lenght encoding?

Yes, with BER the encoder is free to choose either definite or indefinite
length encodings.  Of course, if an application profile dictates that
only one or the other must be used, then you are obliged to use the
specified one.

> And if it's possibile, how can the encoder recognize structures to be
> encoded with definite lenght encoding from structures with indefinite
> lenght encoding? Is there any ASN.1 tag to use? Thanks, bye, Roberto

I take it that you meant to say "how can the decoder ...".  Yes?

If yes, it can tell whether definite or indefinite length encoding was
used based on whether the length field has a value of hex 80.

If no, check with the provider of the tool that you are using.

-------------------------------------------------------------------------
Bancroft Scott                               Toll Free    :1-888-OSS-ASN1
OSS Nokalva                                  International:1-732-302-0750
[EMAIL PROTECTED]                                 Tech Support :1-732-302-9669
x-1
1-732-302-9669 x-200                         Fax          :1-732-302-0023
http://www.oss.com

Reply via email to