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Re: PMS usage suggestions?


You have a lot of good points!
Why reinvent the wheel?
MIR was a working prototype for ISS, but this new TNC
is different than what was on MIR.
The operations and users still remain constant.
ARISS is in control of ISS's TNC, so we will see what they will do.

Yes, APRS is a good way of using minimal bandwtih.
A lot can be said in one line of data, and quick to send.
It is TRUE that anyone on ISS with a computer hooked up to
the TNC can send EMAIL to anyone. (limited to 1 line)
Any HAM on the ground can send an email message via ISS.
This would be useful for campers,travelers,boaters,etc.

FBB,W0RLI, even paKet software can support many users, and
maybe that could be a future project as long as there is a dedicated laptop 
for the operations.

This still does not solve the VERBOSE UI packet connection protocal.
In heavy usage areas such as the USA, a multiport PBBS connection would or 
could be a mess! In areas like Austraila where traffic is low it might work.

73, and have FUN!


>From: "Tim Cunningham" <tim_cunningham@mindspring.com>
>To: "Bob Bruninga" <bruninga@usna.edu>
>CC: <sarex@AMSAT.Org>
>Subject: Re: [sarex] PMS usage suggestions?
>Date: Sun, 3 Mar 2002 19:52:09 -0600
>I have mounds of log data from the MIR Space Station I could present
>to show that 1 minute is not a realistic time frame to do much of
>anything with a single user PBBS connection interface. The TNC on
>MIR was always busy sending rejecting frames to those stations trying
>to connect while another station was already connected. This takes
>time from the connected user who is trying to accomplish their goal
>while connected to the PBBS.
>We cannot rely on the human interface to make this work. History tells
>us it did not happen in all the years the PBBS flew on MIR. Why would
>that change now? If we do not accept that reality, we are only fooling
>ourselves and continuing the same type of activity. Rules imposed on
>the human interface will not fix the perceived problem.
>Solving the problem is a goal, but is there really a problem. Unless
>the purpose and goals of the TNC flying on ISS are clearly defined, then
>we do not know if a problem really exists. So, I took a step back and
>visited the ARISS web page and attempted to review the mission and
>goals for digital communications and found them to be general in
>After reading the posted material, the following thoughts came to
>The PBBS is not suitable for general Amateur Radio operation. This
>could be a perception, but from the numbers of comments on the
>topic over the years I accept it as the reality.
>However, the PBBS can serve the ISS crew very well when used on
>alternate frequencies.
>A dedicated computer is needed to expand experimental operation
>and to expand the capabilities of the currently installed TNC.
>For expanded BBS operation supporting more than one user there
>are several BBS packages like FBB and other programs that would
>support multiple users very easily, thereby eliminating the time
>consumed by the TNC sending rejection frames to subsequent users
>wishing to connect to the BBS. These alternate BBS packages allow
>multiple users to connect. I am not advocating this method, because
>I feel the connected packet mode is not the appropriate choice for
>mass communications if that is the intent.
>For expanded messaging capability much like a BBS, there are
>software packages utilizing the unconnected packet mode of
>operation like APRS (Automatic Position Reporting System). These
>provide a tactical communications system that is more efficient
>than the BBS mode of operation that uses the connected packet
>mode of operation. These systems offer more flexibility in allowing
>ground based stations to marry both RF connections and Internet
>connections to provide continuity when RF line of sight operations
>are not possible. A series of strategically located Internet Gateway
>systems expand the communications system beyond the RF line
>of sight. This system allows messaging capability so that messages
>can be sent and between users as well as the ISS crew.  It offers
>more flexibility than an antiquated PBBS system, but it does
>require a dedicated computer to collect the messages. Perhaps,
>this could be a long term goal. It also offers the ISS crew a way
>to send Internet EMAIL via the APRS mechanism. Now there
>might me an added benefit.
>Tim - N8DEU
>Huntsville, Alabama
> > On 3 Mar 2002, Scott Avery wrote about time to Access the PBBS on ISS:
> >
> > > That is a good question! Considering optimum conditions, and no QRM
> > > would take about 2 minutes.  This includes the connection time,
> > > and reading, then disconnecting.  That would exceed a 1 minute rule.
> >
> > Actually, I think it can be done much faster if the station is ready
> > go.  I think  well under a minute, but I only suggested a minute as a
> > round number that everyone could remember.  Of  course "most" stations
> > will have ZERO success in the actual operating conditions and should
> > even try so that others who do have a chance can get in-and-off in
>such a
> > short time.
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