Re: OIG
Phillip Clark (psclark@dircon.co.uk)
Thu, 11 Jun 1998 19:41:03 +0100 (BST)
Having just done one set of comments about OIG, TLE files, etc, I will
see what there is to respond to here.
I will start off by repeating the comment made in my response to Jeff's
posting: is there a convenient FTP site for SEESATers to which I can post
the files next week while Dave Ransom is away ?
On Thu, 11 Jun 1998, Mike McCants wrote:
> >Just curious, but what is wrong with the service being provided by myself
> >and Dave Ransom about which I posted a message earlier this week?
> There are some things that could be better.
> 1. The service relies on you. If you take a vacation or visit
> a hospital, this service would be interrupted. An obvious remedy
> would be for several other people to also have access to this
> "daily" file.
I have considered finding a trustworthy person to whom I can give my
password so that if there is a problem here then that other person can be
alerted: I will give this more thought. Goddard does advertise the
policy that if an account is abused then it is terminated, which is why
the person would have to be trustworthy !
> 2. There is no service on Saturday or Sunday.
YET. I am told that there is consideration being given to making the
service 7-days-a-week, but I don't know anything beyond that at present.
> 3. The data via this route is about 10 to 12 hours old by the
> time it is available
Today I accessed the Thursday file at 18.00 my time, around 35 minutes
after OIG had added it to the WWW site: I downloaded it, did a little
processing, loaded it back up and by 18.30 it had been sent to Dave Ransom.
My processing it primarily to give the files more meaningful names. The
neames are originally the completely-meaningful tle2mon.zip, .....
tle6fri.zip, and my PKZIP gives a more compact zipped file and I change
the names to (you've guessed it) GDyymmdd.ZIP before re-loading the file.
> Thank you very much. Since it will be another 2 weeks before the
> BBS telnet interface is terminated, I do not have sufficient
> incentive to use your file at present. But when June 30 arrives,
> I will use it and it will satisfy my requirements for the "weekly"
> files I generate.
Maybe an idea to do "dummy runs" before The Day arrives ! Even though
the BBS is still working I switched to the web site a couple of weeks ago
and have used it almost exclusively ever since.
> Wouldn't it be nice if you had an "automatic" system for obtaining
> this file and sending it on?
Maybe I could automate myself ?
> Typical access of the 500K file from this site would
> take about 10 to 15 seconds. It seems very unlikely to me that the
> machine/LAN being used is busy more than 0.01 percent of the time.
I can only pass on the rationale given to me !
> In my message I informed them that our current plan was to use the
> file that you are providing. But not everyone is prepared to handle
> a "Monday" file that expands to 3.7 megabytes. This Unix box handles
> it quite easily.
I wasn't ready either until some software got written !
These days I have an archive system which not only processes a TLE file
into a central archive, but also extracts el sets for some dedicated
archive files which I maintain (NAVSTAR, GLONASS, Oko, Molniya, geosynch
and others): using my 233 machine it takes around 15-20 minutes for a
single file - and that is with software written in QBASIC: I am sure that
other languages could provide more efficient and thus faster code.
Phillip Clark
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Phillip S Clark 25 Redfern Avenue
Molniya Space Consultancy Whitton
Compiler/Publisher, Worldwide Satellite Launches Middx TW4 5NA
U.K.
Specialist in "space archeology" - the older and more obscure the more
interesting it is !
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