home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
World of Ham Radio 1997
/
WOHR97_AmSoft_(1997-02-01).iso
/
packet
/
pak_15
/
amsoft.iii
next >
Wrap
Text File
|
1997-02-01
|
4KB
|
78 lines
ESTIMATE.EXE
This is a new program from KZ1O which estimates how fast you can get data
through a packet network. The program was written in collusion with VITA
(more about them later). It runs on any IBM PC or compatible. The faster (in
megahertz) the better; and even betterer with an '87 chip installed. Any
video board works.
The program allows you to change values of things like FRACK, PACLEN, DWAIT,
and so on, to see what effect it would have on the bytes-per-second throughput
rate of the packet network. A software simulation takes all of your values
and crunches them to get an estimated number, that is, "bytes per second." In
addition, the corresponding times are displayed for transferring typical files
at this new rate.
You use your cursor keys (keypad up/down/left/right) to change the values. To
move the pointer arrow left or right, use the left or right key. To go up or
down to the next parameter, use the up or down key. I'm sort of joking but
also serious when I described that, since it's not always obvious the first
time people run the program.
The F1 key will give you a little help, but this document will tell you
everything that will, and more. To exit the program, press the ESC key.
The program will log each simulation to disk by your command. Press the "P"
key (p for print) to save that set of parameters. By default, the name of the
file that gets this data is named "ESTIMATE.LOG". You can make it a different
file name by specifying it on the command line (this is currently the only
command line option recognized). Remember, DOS treats devices like the
printer similarly to files (that is, call the file "PRN" and you will get a
printout directly on your printer). Page breaks and new headers are included,
of course, when necessary.
------------------------------------------------------------------------------
Once upon a time, Gary Garriott asked if there was a number that you could
multiply by the HBAUD rate in order to get the number of bytes per second. We
sort of guessed that it might be around one third of the maximum, that is, at
300 baud, which is 30 characters per second on a telephone modem, you would
average about 10 characters per second. But as we started to think about the
answer, we realized that there are so many dependent and independent variables
in this equation that you couldn't just say "one third" or "one fourth" or...
really anything! You just have to specify things like FRACK and collision
rate and PACLEN and everything else! So this hairy page-long equation was
designed (by KZ1O), based on experience and on some of the data returned by
the MONAX25 program, and then coded into a C++ program. Then a way of
entering the values was devised, and the whole thing was buttoned up and
debugged. And what you have in front of you is Gary's answer!
-----------------------------------------------------------------------------
This is another shareware program from Dave Bushong, KZ1O. Because of who
will be using it, Dave chose to make it a free, but copyrighted program. If
you use it, you must register it. There is no fee for registering it. Send
your name, address, callsign (if any) to:
Dave Bushong
7 Fremont Street
Concord, NH 03301-3923
If you want the latest version, include ten dollars (US or Canadian). Other
countries, send US funds! If you want the source code also, please specify
why you do and it will be included.
-----------------------------------------------------------------------------
VITA is Volunteers In Technical Assistance. They lend technology to
developing countries. One of the real needs in developing countries is
communications. Packet radio lends itself to this need. It is portable,
error-free, and cheap. There is a pool of skilled radio operators that are
willing to volunteer their time and energy to help (that means you?). For
more information about VITA you can call:
(703) 276-1800 (voice)
(703) 527-1086 (3/12/2400 baud BBS)
[eof]