Protocol scope and method
The common header carries the platform identifier as an unsigned four-byte integer. Business meaning is assigned by the platform profile.
uint32 decimal ↔ four-byte big-endian hex.
Common questions
Does the JT/T 809 Platform ID Converter leave my browser?
No application upload is used. Avoid putting sensitive production data in shareable URLs.
Is this a standards compliance test?
No. Confirm the edition and vendor profile with licensed documents and your target platform.
Offline diagnostic aid. Verify fields, version and vendor extensions before production use.