<p>It doesn't really matter. PSBT parsers that don't understand the proprietary type will safely ignore them, and those that do will already need to know what the actual bytes are and can just do a byte comparison regardless of the encoding.</p>

CC BY-SA 4.0
2023-03-06T20:18:03.333Z
So, does it mean, here string identifer in the bip is just a suggestion? The actual data type that can be stored as bytes is totally up to the user of the proprietary key-val user?
solar
CC BY-SA 4.0
2023-03-06T22:34:00.620Z
Yes, the data is just bytes.
Ava Chow
CC BY-SA 4.0
2023-03-07T14:34:33.813Z
Thank you Andrew.
solar
CC BY-SA 4.0
2023-03-06T18:30:51.190Z
2023-03-06T18:30:51.190Z
Ava Chow
<p>Looks like bip174 doesn't specify string encoding (utf8, ascii) for <strong>bytes identifier</strong> field of <strong>PSBT_IN_PROPRIETARY</strong> key.</p>
<p>Now how a psbt lib can check if the <strong>bytes identifier</strong> is a a valid string bytes or not?</p>
<p>Otherwise, any non-string bytes can also be stored in <strong>bytes identifier</strong>.</p>
<p>Ref <a href="https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki#proprietary-use-type" rel="nofollow noreferrer">https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki#proprietary-use-type</a></p>

<bip174-psbt>
PSBT: What string encoding is recommended for identifier field of PSBT_IN_PROPRIETARY key?
solar
# PSBT: What string encoding is recommended for identifier field of PSBT_IN_PROPRIETARY key?

(Asked by: username_0 on 2023-03-06)

Looks like bip174 doesn't specify string encoding (utf8, ascii) for **bytes identifier** field of **PSBT\_IN\_PROPRIETARY** key.

Now how a psbt lib can check if the **bytes identifier** is a a valid string bytes or not?

Otherwise, any non-string bytes can also be stored in **bytes identifier**.

Ref <https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki#proprietary-use-type>

**Tags:** bip174-psbt


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## 1 answers

### Answer by username_1 on 2023-03-06. Score: 1 | Accepted answer

It doesn't really matter. PSBT parsers that don't understand the proprietary type will safely ignore them, and those that do will already need to know what the actual bytes are and can just do a byte comparison regardless of the encoding.

> **Comments:**
> **username_0**: So, does it mean, here string identifer in the bip is just a suggestion? The actual data type that can be stored as bytes is totally up to the user of the proprietary key-val user?  
> **username_1**: Yes, the data is just bytes.  
> **username_0**: Thank you Andrew.  

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