Re: [Fwd: [emergency] Questions on ASN.1 and IPAWS Profile / CAP 1.2]

[Jacob Westfall <jake@jpw.biz>]

> representation of CAP 1.1 was. That  was why I said that this was the 
> "first time I heard ASN.1 encoded CAP messages in
> relation to any US-specific implementation..."  

I too have not heard of any US specific implementation, but I've also not heard of any European ones either :)  Actually outside of the H.323 work is anyone else aware of CAP ASN.1 implementations, it would be good to know as a reference and to get their feedback on any problems and areas of improvement.

The original question I believe was regarding XML to ASN.1 translations and the IPAWS Profile.  While the IPAWS Profile doesn't have any explicit references to ASN.1, it also doesn't contain anything specific to XML only, and there should be nothing that prevents ASN.1 encodings of IPAWS Profile messages.  I have little experience with ASN.1 however and would certainly be willing to work with anyone who has ASN.1 expertise to test and prove this.

Regarding XML to ASN.1 translations, while it should be possible, there is a concern here.  One of the major reasons for CAP 1.2 was correcting the schema to include XML Digital Signatures/Encryption.  However DSig's don't translate over into ASN.1.  So if you were translating from XML to ASN.1 the DSig will be lost and some other, probably transport related, security mechanisms would be needed.  Translating back to XML from ASN.1 would be even more problematic as you would have to resign the XML message for DSig, and if you were to compare the original XML DSig to the translated XML DSig they would not match.  Again though, take my comments with a grain of salt.  I'd certainly like to see if there is someone with ASN.1 expertise who would be willing to also test this out.

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jake@jpw.biz
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