Why was the default representation for size-constrained OCTET STRING values changed to UNBOUNDED instead of VARYING as before?

Beginning with the OSS ASN.1 Tools 5.0.2 the default representation for OCTET STRING values was changed to UNBOUNDED if the size constraint exceeds 256. The reason was that OCTET STRING is one of the most frequently used ASN.1 types and having it generated as an array (VARYING) was not good as far as performance goes, especially for values with small sizes.

To obtain the former behavior the -compat v4.2octetstringdefault ASN.1 compiler command line option can be used or the --<VARYING>-- directive applied to the OCTET STRING type:

O ::= OCTET STRING (SIZE(1..4095)) --<VARYING>-- 

The samples included with some of the Knowledge Center answers are meant for your general understanding of the OSS products. Different versions of the products might produce slightly different outputs. Consult the products documentation and samples for the most up-to-date products information and code examples.

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