Am I old-fashioned to raise an eyebrow when I discover that Memcached servers are running visible to the public Internet? This strikes me as approximately as bizarre as having a database server that accepts connections from the public Internet.<p>In my day, such back-end services were either simply not connected to the Internet (connected via a private network to the application services), firewalled, or at the very least, configured to listen for and respond exclusively to connections from known front-end or application services.<p>Is this sort of deployment architecture falling out of favor? My casual observation is that cloud architectures—at least the ones I've seen employed by small organizations—are more comfortable than I am with services running with public IPs. What is going on? Am I misunderstanding this in some way?