One service which George O Smith has provided is to force us to question our assumptions on how communications work up to Earth/Mars aphelion opposition. Round up to 3 AU.
Smith figured that communication would be beamed to us - that is, focused radar. Unfortunately he also figured that the communication would be by telegraph and Morse, basically; "QRM - Interplanetary"'s MacGuffin is just a short request (from Venus to Earth) for some trivial supplies. If that's all we need then Voyager 2 - speaking from interstellar plasma - is still talking to us (not so much V'ger-1). There's no "beaming" from that distance. Anyone in our inner solar system can listen in. Admittedly this is done at the 2.3 GHz or 8.4 GHz "S Band", more microwave than true radio; this limits bandwidth to 16 b/s (never mind latency).
So Smith didn't have to beam his signals. For Earth his station just has to aim in our general direction. If we're concerned with secrecy then we can share a cypher: "message start, use this key, transmitting, end transmission". Although, yes, I can agree the Sun interferes with this frequency.
A high-bandwidth solution might be for lasers. This has been done from 0.2 AU: we can get 267 Mb/s cat vids.
This craft is en route to 16 Psyche; the recipient is here on Earth, scil. Caltech: Palomar, Hale Telescope. If we have an interworld Web then this can be scaled indefinitely. Also in space we're not restricted to the S Band; although if so, something in orbit - maybe a GEO chain - will need to translate all the beamed messages into S band for wellwalla consumption.
To sum up: beaming is great, but to make SVL4 worth it, the communicants need to be beaming more than telegrams and telemetry.
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