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Comment by ttyprintk | Hacker News Reader

Among those binary formats, this one benefits from the ubiquity of OpenSSL (see asn1parse) for debugging.

ASN.1 is all over the place in low-level networking protocols. That is where I learned it, two decades ago. While I disliked it initially, it was thoughtfully designed albeit obviously from a prior era.

Also, turns out that if you work with it long enough you can read the binary encodings almost like it is text.

> can read the binary encodings almost like it is text.

I'm curious what encoding rules that applies to: BER/DER I could easily believe, aligned PER a bit less so, and unaligned PER with lots of extensions and optional parts would be impressive.

It's the underpinnings of snmp too. ASN is one of those things that's everywhere you've never looked

I worked on a SNMP Go package many years ago [0] and it was really fun learning about ASN.1 and figuring out how to write encoders and decoders for various types.

[0] https://github.com/Cistern/snmp

The cellular network standards (GSM/xG) use it heavily too.

All of OSI stack used ASN.1 extensively, something that would have made building protocol implementations much easier than text-based IETF style.

SNMP is, IIRC, inspired by much more capable CMI which was part of OSI stack of protocols and is still used in some high end WAN network gear for monitoring and control (whereas "write" aspects of SNMP have mostly disappeared)

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