First computer network in space?

What was the first system flown in space that qualified as a computer
network? I think the CM and LM computers on Apollo could send/receive
data to each other, but does this ability alone make as a network? Or
did a true network not go up until the ISS?

"Matt" wrote in message
...
What was the first system flown in space that qualified as a computer
network? I think the CM and LM computers on Apollo could send/receive
data to each other, but does this ability alone make as a network? Or
did a true network not go up until the ISS?


As far as I know, the CM and LM computers could NOT send/receive data.

Skylab had an early version of the shuttle computers, but I wouldn't really
call that a network as much as a cluster (if it indeed had more than one,
which I think it did.)

My guess is MAYBE Mir, but I never heard reference to one. So yeah, I'd
guess ISS.



--
Greg Moore
Ask me about lily, an RPI based CMC.

Greg D. Moore (Strider) wrote:

My guess is MAYBE Mir, but I never heard reference to one. So yeah,
I'd guess ISS.

That would depend on what you refer to a computer network as.
The Soviet IGLA fully automated rendezvous and docking system relied on
both spacecraft transmitting and receiving data on the other's position,
so if you want to call that a network, it would go clean back to the
first rendezvous of two unmanned Soyuz spacecraft in the the Cosmos
186-188 mission and their docking on Oct 30, 1967:
http://en.wikipedia.org/wiki/Cosmos_186
Cosmos 186 was the active partner in the docking, but Cosmos 188 had to
keep itself properly aligned in relation to 186 for the docking to succeed.
As usual, Sven Grahn has a great article on IGLA he
http://www.svengrahn.pp.se/histind/RvDRadar/IGLA.htm
Did Gemini establish any sort of communication with the Agena before
docking to it?

Pat

Matt wrote:
What was the first system flown in space that qualified as a computer
network? I think the CM and LM computers on Apollo could send/receive
data to each other, but does this ability alone make as a network? Or
did a true network not go up until the ISS?

In order to answer that question, you need to specify what you think
"qualifies" as a "true" network.

The CM and LM computers (CMC and LGC) could not communicate with each other.

The LM AGS computer (AEA) could listen to the LGC, but not vice-versa,
so it was not two-way communication.

The space shuttle GPCs had two-way communication with each other
(intercomputer communication buses) and with a databus network
consisting of eight flight-critical buses, two launch data buses, two
payload buses, four display/keyboard buses, and two mass memory buses.
The databus used was an ancestor of the MIL-STD 1553 bus. I think this
qualifies.

If nothing but bog-standard Ethernet qualifies for you, I think the
space shuttle was still first. Its laptop computers were networked with
10Base-2 as early as 1994, I think. 1995 at the latest. That was 3-4
years before ISS.

"Jorge R. Frank" wrote in message
...

If nothing but bog-standard Ethernet qualifies for you, I think the space
shuttle was still first. Its laptop computers were networked with 10Base-2
as early as 1994, I think. 1995 at the latest. That was 3-4 years before
ISS.


Hmm, didn't even dawn on me that might have happened. I can definitely see
that on a Spacelab flight.



--
Greg Moore
Ask me about lily, an RPI based CMC.

On Wed, 22 Apr 2009 17:17:51 -0400, "Greg D. Moore \(Strider\)"
wrote:

"Matt" wrote in message
...
What was the first system flown in space that qualified as a computer
network? I think the CM and LM computers on Apollo could send/receive
data to each other, but does this ability alone make as a network? Or
did a true network not go up until the ISS?


As far as I know, the CM and LM computers could NOT send/receive data.

I know the CM and LM computers could get state vector updates from
the ground through P27 (at least that was the pgm number on Apollo 15,
which is the only one I've got computer docs on)--not sure if they
could "talk" to each other directly, but for rendevous, they had to
know where the other one was. They may have gotten the state vector
info on the other vehicle from the ground.

take care,
Scott

Scott Stevenson wrote:
On Wed, 22 Apr 2009 17:17:51 -0400, "Greg D. Moore \(Strider\)"
wrote:

"Matt" wrote in message
...
What was the first system flown in space that qualified as a computer
network? I think the CM and LM computers on Apollo could send/receive
data to each other, but does this ability alone make as a network? Or
did a true network not go up until the ISS?

As far as I know, the CM and LM computers could NOT send/receive data.

I know the CM and LM computers could get state vector updates from
the ground through P27 (at least that was the pgm number on Apollo 15,
which is the only one I've got computer docs on)--not sure if they
could "talk" to each other directly, but for rendevous, they had to
know where the other one was. They may have gotten the state vector
info on the other vehicle from the ground.

That's correct, at least for the initial update. For example, after LM
ascent, MCC would evaluate the LM state vector from the LM downlist and
uplink it back to the CSM. It was not possible for the LM to transfer
its state vector directly to the CSM. They could not talk to each other.

After that initial MCC update, the two vehicles used rendezvous
navigation (P20) to update state vectors. The LM used data from the
rendezvous radar (range, range rate, shaft and trunnion angles) to
update the LM state vector in the LGC, and the CSM used data from VHF
(range) and the sextant (shaft and trunnion angles) to update the LM
state vector in the CMC. In both vehicles the CSM state vector was not
updated because, as the non-maneuvering vehicle, its state vector was
considered to be better-known.