In message , at 11:04:05 on Fri, 7 Dec 2018,
Recliner remarked:

Do any self-driving cars depend, or plan to depend, on continuous, reliable
access to a data network? It sounds most improbable. How would they
operate at all on remote roads with no signal?

They will need periodic access to update their mapping data, report back to
base, or update software, but shouldn't need continuous access.

It's been said that if in a situation of gridlock on a stretch of road,
the cars would communicate with each other to decide a priority to
proceed.

That's a more immediately real time situation than still importantly
attempting to avoid obstructions occurring at short notice such as RTAs,
and this week Network Rail closing the A10 level crossing at Littleport
for hours, so they could get machinery in place to fix a broken rail.
--
Roland Perry