demonstrative or pronoun?

[Johannes Reese]

> Consider the following very similar contexts;
>
> Context A:
> John and Bill are friends.  John calls Bill on a landphone; it's a bad
> line, Bill doesn't know who is speaking; John tries to identify himself
> (using a predicate nominal construction)...
>
> Context B:
> John and Bill are friends.  John sends Bill a text message from a new
> number that Bill is unfamiliar with; John identifies himself (using a
> predicate nominal construction)...

Dear David Gil,

I would use neither construction in German.

#Dies ist John
???Ich bin John

Rather a (somehow senseless) locative adverbial:

Hier ist John.

Regards,

Johannes