dvr trying to view over internet please help

[carlos17]

i have rigged up my avtech dvr no probs there network cable got access
via wi fi round house even can view on my iPhone 4 but say im away in another country and i want to view my dvr and ive got wifi in the hotel what do i type into my browser do i type in my public ip or my dyndns server name or my host name i have tried to type in my public ip but a web page comes up called anytime anywhere surveillance but keeps saying authentication failed any advice would be very welcome thanks