Unidirectional Serial IP.

[Patrick Vielle <patvie@ce.ife.org.mx>]

Hello,

I have read part of your web pages concerning UniDirectional Link Routing
(http://www-sop.inria.fr/rodeo/udlr/) and would like to ask some questions
although they are not directly related to the routing proposals but
actually related to what I believe could be your technical experiences
with Satellite Unidirectional data transmissions.

I have just been involved in a project that plans to build a scholar
national network in Mexico. The planned operating system installed in each
network would be Linux. 

Please see: 
http://luthien.nuclecu.unam.mx/~arturo/scholar/

Currently the project plans to connect most of the mexican public schools
to the internet by building a small network of computers in each shool and
connecting each network trough a linux server via dial-up (IP_MASQ) to the
nearest ISP. As part of this project each shool is equiped with a General
Instruments TV receiver that we discovered has a 19200b/s rs-232
connector. We have made some tests and have been able to transmit data and
receive it without problems with laptops connected to both sides via the
DB9 rs232 connector.

These General Instruments Receiver has another DB9 port wich is supposed
to be a Synchronous serial RS-449 (DB9??) but we do not have the pinout of
this port so as of now we have not being able to test it. (As you know
General Instruments

We would like to use this serial Uni-directional transmission medium to
receive unicast broadcast or multicast data; however we are almost
clue-less on where and how to begin. We would like to know for example if
it is possible to establish some kind of ppp unidirectional link
connecting the linux server directly to the serial port.

Any help insights to bulding the first step which is the datalink layer
would be greatly apreciated. 

Patrick Vielle Calzada
Insituto Federal Electoral
(in cooperation with the scholar net project)