system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars/general Sci-fi] Interplanetary Internet?

Persay I want to play space WoW with my friend, I live on Coruscant, he lives on Corellia, is this even possible? Can i email my crazy estranged uncle on tatooine? 

In BSG how would I keep in contact with a friend on one of the other colonies?

Same thing for other mainstream sci-fi universes?
gpt
In Star Wars, they have an interstellar Holonet, connecting at least all of the core world, and with limited access beyond.

In BSG, interplanetary communication is typically conducted through couriers, or laser burst communication. It is not real time and suffers from some significant delays. 

In 40k... No one really has access to anything like an Interplanetary Internet. Even the Eldar and Necrons didn't have it. 

Starcraft has limited interplanetary networking, but again even the Protoss typically use couriers to convey important information to their colonies.