[aprssig] APRS web messaging

[wa7nwp at jnos.org]

> I figure you could have the system give a new user a code that must be
> sent
> via RF into the network to authenticate themselves.  It'd be inconvenient
> for the user if they're not set up for it or don't have a local IGate, but
> it doesn't require intervention.


APRSPLUS, or one of Brents follow on projects, had a page for sending
messages authenticated with the users code for Aprsplus.   We could do the
same with the aprs-is callpass functionality.