A single TCP socket may not be reliable, but I understood the parent comment at the application layer. With enough redundancy, checks, retries and caches, it's

A single TCP socket may not be reliable, but I understood the parent comment at the application layer. With enough redundancy, checks, retries and caches, it's possible to conduct business reliably[1] over the internet, tolerating failures from nearly any component involved along the way. [1] By "reliable" I mean with an uptime satisfactory for the application involved. Nothing is ever 100% but we can get pretty darn close in terms of probabilities.