Re: Project Star Net

Anders Sandberg (asa@nada.kth.se)
23 Apr 1998 15:03:52 +0200


tlbelding@htcomp.net (Tony Belding) writes:

> I am proposing an idea, and I would like to see if there's any enthusiam for
> it among extropians. In short, Project Star Net (PSN) would aim to establish
> an interstellar communication network. Right now PSN is still in the
> "thinking about it" stage, and I want to see if there's any interest in
> forming an organization to pursue this worthy goal.

> I envision a station (or node) in each stellar system with powerful
> transmitters and receivers, thus allowing data to be relayed to a
> specific destination, or propagated through the network as a general
> broadcast.

Why just one? I assume the energy needed for interstellar
communication would be relatively manageable if it is properly
collimated (no need for Forward's wonderful megascale lasers needed
for fast interstellar solar sailing), so even if there are scale
factors making it economic to have large transmittors there is likely
no reason to have just one. The same goes for receivers.

> A major goal would be the translocation (or "faxing") of persons across the
> network.

Bandwidth, error correction and receipts will be important
here. Assume a human mind takes around 10^15 bytes - that will require
a quite large bandwidth.

> Because of the sheer size of the network and the associated netlag, it could
> not be centrally managed. In fact, once the first node is established, the
> Star Net should automatically manage and maintain itself, and launch "seeds"
> to establish new nodes, thus replicating until it ultimately spans our entire
> galaxy. This will require a certain level of artificial intelligence.

Charlie Stross has a StarNet-like network in his novel Scratch Monkey,
where some of these issues are discussed. I recommend it, even if I am
doubtful about some of his solutions (which on the other hand makes
the novel more interesting).
http://www.antipope.org/charlie/fiction/monkey/index.html

> * What is the most efficient way to launch "seed" probes across
> interstellar space? Also, how small can such seeds be made?

I have started writing up a nanotech seed for this purpose, I have a
(not very finished or well planned) draft at
http://www.nada.kth.se/~asa/Hx/seed

My idea is to use a laser-driven solar sail to propel it, with perhaps
a magsail to brake and a small solar sail for traveling
in-system. Asteroids are seeded with nanomachines that build a
receiver, which then recieves further instructions. My guess is that
the whole seed would be fairly small, likely less than one meter or so
(possibly much smaller).

Maybe we could develop the draft together, hopefully with useful input
from the list?

> * What types of star systems should be candidates for
> establishing nodes?

Why not every system? There are likely asteroids everywhere, and extra
capacity is likely a good idea.

> * What part or parts of the EM spectrum are suited to our use.

My communications technology knowledge is limited, but I would guess
we want short wavelengths for maximum bandwidth (drawback: requires
more energy to send than long wavelengths). Lasers sound fine to me.

> * What are the practical limits of data throughput across
> interstellar distances?

Intensity fall-off (eventually you reach a bad signal-noise ratio),
dust and other obscuring stuff, alignment problems.

> * What are the data requirements of transmitting a person? What
> if the traveller is enhanced with extra memory -- do you charge
> by the gigabyte, or have a fixed rate for everybody?

Rough estimate: 10^11 neurons, 10^4 synapses each, five bytes per
synapse (where it is connected, synaptic strength) = 5*10^15 bytes. If
you want to scan the whole body, you will need *huge* amounts of
bandwidth (remember, one mol is 10^23 atoms...).

> * What other types of data might be transmitted? Free news,
> perhaps?

Just look at the net - everything from net control messages over
discussions to posthuman pornography (scantily clad jupiter brains?).

> * How can access to the network be allocated fairly?

I think the Internet model works fine: make it easy to connect, you
only pay for your node in the network which both gives you access and
acts as a part others can use.

> * What is the most likely way to finance the project?

Note that if you use reproducing probes, you only need to pay for the
original probe, and then it will expand on its own giving a huge
return of investment. A good start might be an interplanetary net.

> * How will the network respond if it "bumps into" an alien
> civilization?

Protocol trouble, but hopefully the SNETF (StarNet Engineering Task
Force) is up to writing an adapter. Obviously, selfreproducing probes
need to be given good emergency programming.

> * If a star system is over-populated, can its inhabitants tell
> their station to refuse any new arrivals? Are there other
> situations that could justify this option? And what happens
> to the traveller who the station doesn't accept?

Look at the net: an overloaded router tells the other routers that it
is busy, and they route signals elsewhere. If travel is done by
sending a copy of the traveller to the destination, keeping one copy
inactive, and then waiting for a receipt (if received, delete the
inactive copy, otherwise awaken it and tell it "sorry, access
denied"), there is no big problem with occasional blocks.

Stross has an interesting scenario in Scratch Monkey where some
desperate people flee just by broadcasting themselves in the same
direction, hoping they will be picked up.

> * What kind of data security is required on transmissions?
> What degree of encryption, error correction, and redundancy
> is desirable?

Error correction (= redundancy) is important. Encryption is best left
to the application layer, although it might be a good idea if the
nodes in the network use some autentification software. Sounds like
conventional internetworking problems.

> Does it makes sense to form an official organization at this
> point in time?

I'm torn between "no" and "maybe". It would be interesting to think
about the project, but it is still rather far in the future and the
form of StarNet will be highly dependent on unknown future
developments in information technology, nanotech and AI. I suggest the
idea is developed further, and StarNet is designed to be an initial
proposal others can refine. Then, in a few decades, it might be time
to form the real organization.

BTW, are there any standards yet for domain names in space?

-- 
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Anders Sandberg                                      Towards Ascension!
asa@nada.kth.se                            http://www.nada.kth.se/~asa/
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