ASN.1 Tools for C# — Overview


The OSS® ASN.1 Tools for C# is a powerful development tool for rapidly building applications using ASN.1.

This product features a powerful ASN.1:2021 capable compiler, a runtime DLL with ASN.1 BER, DER, PER/UPER, CPER/CUPER, XER, CXER, E-XER, OER, COER, and JSON encoder/decoder engines, and a rich collection of utilities to simplify and speed your development.

High Performance

Our ASN.1 products support LTE Advanced Pro including NB-IoT, C-V2X and LTE-M. OSS products support the 3GPP 5G specifications.

Support for
.NET Standard 2.0

The compiler takes ASN.1 specifications as input, and generates C# language classes. In addition to core functionalities, the OSS ASN.1/C# compiler offers extensive diagnostic capabilities to minimize your development time and effort.

Compatible with
.NET Core, UWP, and Xamarin

A runtime DLL provides ASN.1 encoding and decoding functions and auxiliary functions to operate on application messages.

Support for
Partial Decoding

Support for JSON Encoding Rules allows serializing ASN.1 data to the popular JSON format and converting between JSON messages and ASN.1 binary messages.

Support for

Support for OER allows working with ASN.1 binary messages that can be encoded/decoded significantly faster than BER and PER messages, while being only slightly less compact than PER messages.

Support for E-XER allows generation of XML compatible with output from XML Schema tools.

ASN.1 Tools for C# features
  • Backward compatibility guaranteed
  • ASN.1 Studio, an intuitive IDE for ASN.1 specification editing and message analysis
  • Support for partial decoding
  • Large INTEGERs (for cryptographic applications, no upper or lower bounds)
  • Encoding of extensible types (unknown extensions)
  • Rich set of C# representations for ASN.1 types
  • Automatic decoding for any kind of constraint
  • Contents constraints (full support)
  • No implementation restrictions; never rewrite your ASN.1 to accommodate encoding limitations
  • File and socket support
  • Concatenated PDU support
Standards Conformance

For a list of the ASN.1 standards that the OSS ASN. Tools for C# conforms to, see the Standards Conformance page.

Free Trial

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24x7 Tech Support


We are here: 24 hours a day, 7 days a week.

  • Phone: 1-888-OSS-2761 (USA and Canada)
  • Phone: 1-732-302-9669 (International)
  • Fax: 1-732-302-0023
  • Email:

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