The term “trust” in blockchain refer first to “custody” then to “believe/confidence”.
Blockchain is trust-free (i.e. “custody” free) because it doesn’t need certain (and fixed) party/node to keep the information. They are distributed among (freely maintained) party/nodes (in so called distributed ledger -> which has nothing to do with financially termed ledger)
And these information is encrypted with a block and chain method.
That makes the information (distributed and chained-encrypted) can be “believed” as reliable.
Blockchain is trusted because it is trust-free
And I see that blockchain is good for data that is transactional, not static (use static encryption for this: PGP, SSL, PKI, etc).
In crypto-currency the important information kept in blockchain is the transaction, not the coin itself, i.e who buys how much at what time from whom. This proves the ownership of the coins.
For the university certificate discussion above, I see blockchain is good not for keeping the certificate per se. But for the issuance of the certificate (from univ to student) like @f_deryckel said, and for proof-of-ownership when the student needs to show it to third party, for example when he applies for job. Or if he wants to pawn it…
Back to ERP.
So what is hypothetically good to be blockchained is the transactional (or as @max_morais_dmm mentioned as process) in the system such as creation or amendment of a document (not necessary the data inside the document itself, which can be kept in conventional database). This creates immutable transaction (transaction records that only goes forward).
Or use smart-contract to create self-release transactions when certain conditions are fulfilled, e.g. salary payment, purchase payment, quality approval, etc.
Hence blockchain can be good for audit.
@alkuhlani so if you want to make something, maybe you can create a SaaS which ERPNext user can send a document (e.g PO) to his account in your SaaS to be stamped (i.e put in blockchained) before sending it to the vendor.
But again… implementing distributed-ledger must consider the need of many nodes, which might make it not practical for internal or single-party use.
Finally, my view regarding ERPNext is don’t do it… at least not now. Maybe for version 20 is ok