[tomek_zemla]

It has been noted by number of analysts that it is surprising that Ukraine still has access to Internet. Everybody expected cyber warfare to be a major part of the invasion. One of the possible explanations mentioned: Russian army and its covert operatives need it.

[Ennergizer]

Ukraine has one of the best fiber optic and cable network systems in the world built 10-15 years ago. It had mobile internet in subway station and between subway stations in 2002-2004, way before anyone in the world.

[malloryerik]

Is the internet and electricity being on not possibly because the invaders don't have air superiority?

[dboreham]

Also packet switched networking was invented to tolerate enemy bombing.

[d82nsjk9]

Makes sense, but source?

[hnlmorg]

You're being downvoted for a fair question. I wouldn't exactly cite this as a source to the GP's claim but it does still answer your question: https://en.wikipedia.org/wiki/Packet_switching#History

[d82nsjk9]

I guess I may have come across as rude or lazy for not googling it myself :) Thanks!