Hi Jihye, try: http://www-sop.inria.fr/rodeo/personnel/hoschka/asn1.html to get an overview of ASN.1 products. The OSS ( http://www.oss.com) ASN.1 compiler, which is commercial, support the packed encoding rules, which are required for H.323. Frank -----Original Message----- From: pjh [mailto:pjh@DESKVIEW.NADA.CO.KR] Sent: 04 March 1999 10:55 To: ITU-SG16@MAILBAG.INTEL.COM Subject: question: asn.1 Dear ITU-SG16 experts I am searching for commercial or free ASN.1 compiler . Further details are as follows: Features: o ASN.1 to C or C++ source code compiler ( A run-time version of the source code is available) o Fully supports ASN.1:1997 o Library of low-level PER encode/decode functions o Compiler has been tested on following RealTime OS: pSOS, vxWorks, Ets kernel If you are using ASN.1 compiler on RealTime OS, Please let me know where I get it. Please reply to this E-Mail Sincerely, Jihye Park(Miss) Nada Research Co., Ltd. Seoul 137-070 , Korea Tel: 82-2-525-3941 Fax: 82-2-525-3945 pjh@deskview.nada.co.kr < mailto:pjh@deskview.nada.co.kr>