I just reviewed this thread, and I must say that using SMTP and MIME
content-types appears to me to greatly expand the range of things you
can do with paging.
If you want one-hop relaiability, then you configure your neytwork to
be able to always reach the pager station in one hop, or notify
someone that one-hop service is not available at the time.
Unavailability can be due to the pager station being out of service,
or due to some obstacle that can be routed around iwth a bit of store
But, the big plus I see for simpoly using SMTP is that anyopne
anywhere on the Email Internet can also reach the pager with ordinary
mail. Of course it will be important for them to understand the
difference in the Quality of Service.
But, I see no reason why SMTP is not as good as your new SNPP when it
is used over a one-hop configuration.