[IGSMAIL-3847]: Message for igsmail

[mkenney at igscb.jpl.nasa.gov]

******************************************************************************
IGS Electronic Mail      26 Apr 09:31:43 PDT 2002      Message Number 3847
******************************************************************************

Author: Ron Muellerschoen, Ken MacLeod, Mark Caissy

There was substantial discussion at the recent IGS workshop in Ottawa on
real-time flow of GPS data.  Specific concerns were the underlaying
protocol, TCP vs UDP, and whether organizations will be able to open there
firewall to a specific port number.  We call on organizations to
participate in a simulated data flow test, using both protocols for the
week of April 29 to May 3rd.  We have designated a target portnumber for
both protocols as 3738. (Currently the IANA registered port numbers in the
range of 3738 to 3801 are unassigned. )

We ask organizations interested in participation to run clients at their
sites and provide back to us input on access problems, success rates, and
latency issues, with both protocols.  We would prefer to see clients run
simultaneously, and looking at different servers on various IP providers.
The more clients hitting these severs, with the different protocols, the
more information we can quickly obtain on how to build the final iGPSDR
system.

Additional information to obtain and run the clients and can be found at:

ftp://sideshow.jpl.nasa.gov/pub/rjm/client_igs/README

Please experiment with the different servers, and with a different number
of site requests.  Shortly the igs central bureau will establish an rtwg
mailing
list.  Once this has been established, please respond to
rtwg at igscb.jpl.nasa.gov
with your findings.  We would be interested in hearing about data latencies
as listed in the log files, the success rates as listed in the summary
files, and the number of dropped connections.  We are particularly
interested in hearing about the differences you see between a TCP
connection and a UDP feed.

thank you for your efforts, and best regards,

ron,ken,mark