[did-core] Why there are two different Ids in a single DID document?

Hi, I’m a student in department of Computer Science and Information
Engineering, National Taiwan University. I’m studying about the how DID
works (reference: Decentralized Identifiers (DIDs) v1.0. However, I’m
confused that in “EXAMPLE 13: verification methods using publicKeyJwk and
publicKeyMultibase “, there are two different verification methods with
different  “id” (did:example:123 and did:example:12345678…fghi), but the id
in the document is “did:example:12345678…fghi”. Is that a mistake? Or I
misunderstand the meaning of the “id” parameter?



Thank you for your time. Hope this question would be helpful.



best regards

Lager Wu