Subject: QPSK modulator card

From: Olaf Menzel <[email-masked]>
Date: Thu, 6 Jan 2000 10:57:47 +0100

Hello,
-----

we have successfully tested LINUX kernel 2.2.x for using it in sattelite
enviroment. We have build up a squid proxy array and have used ipchains as
tranparent proxy with port mapping. 

Right know we think about using a LINUX PC as a VSAT station. Therefore we use
a DVB card for receiving the big forward channel. For the back channel we want
to use a QPSK modulator card.  Probably we have to implement a LINUX kernel
driver and a API. Maybe there is already a PC QPSK modulator card with LINUX
driver avaiable ? As I have looked to the Internet I could not find any
avaiable QPSK card for PC. Does anybody of you  have any information ??

Thank you and many regards 

Olaf Menzel

---
Dipl. Ing. Olaf Menzel - System Engineer
GMD - German National Research Center of Information Technology
dept. SatNET
Schloss Birlinghoven, 53754 Sankt Augustin, Germany
Phone: +49-2241-14-2252   Mobile: +49-171-9148395    Fax: +49-2241-14-1050
email: [email-masked]         Internet: http://sat.gmd.de

---

From: "Robert Schellhase" <[email-masked]>
Date: Thu, 6 Jan 2000 11:46:42 -0500

Olaf,
Here are some companies you could talk to. I don't know whether they sell
exactly what you are looking for, but it is a place to start.

Shiron http://www.shiron.com/
CyberStream http://www.nmcfast.com/
Gilat http://www.gilat.com/

Best regards,
Robert Schellhase
Senior Engineer
INTELSAT

---

From: "Dr. Dieter Pukatzki" <[email-masked]>
Date: Mon, 10 Jan 2000 09:03:48 +0000 (UTC)

Olaf,

> tranparent proxy with port mapping. 

I would be interested in knowing more about your setup, because I cannot
follow what you are doing and would like to compare what Klaus and I are
doing in Kalimantan (yes, of all places, Kalimantan, Indonesia).

Here is what we got working:

                                                               |
                                                               |
                                                    Linux PC ---  NT LAN
                                                               |
                                                               |
                                                   /
                                                  /
Linux PC <---->VSAT II modem by NSI <---> carrierer /
                                                 \
                                                  \
                                                   \
                                                    Router ISP Wasantara

                                                          INTERNET

The idea is not to use a single channel per carrier (SCPC), nor a hub
(star system). Money is a primaray issue here in Indonesia and consequently,
we have set up a mesh DAMA and therefore an number of VSAT sharing
transponder space on mabuhay (philippino) satellite. We are still
at the testing state, but so far so good, except

	we do'nt get a better transfer rate than 4 K/sec.

   Any idea what to expect?

> Right know we think about using a LINUX PC as a VSAT station. Therefore we use

	I suppose this "replaces" of an external modem , using somesort of
	internel QPSK card? What brand, what software?

> avaiable QPSK card for PC. Does anybody of you  have any information ??
as to lett: I taught the first C seminars at your institute some 14 years
ago and presently compterize with Klaus Lichtenwalder palm oil and
rubber estates in Indonesia, using Inter- and Intranet techniques. Terrestial
we are up and running 95%+ for a year terrestially (in Indonesia!!!) 
and now going satellite. All with Linux

want see what our place looks like? www.ptpn13.com

Dieter