[IGS-RTWG-4] IGS RT Network Prototype and Preparation for Berne Meeting

["Caissy, Mark" <caissy @ NRCan.gc.ca>]

******************************************************************************
IGS-RTWG Mail      06 Oct 11:10:33 PDT 2003      Message Number 4
******************************************************************************

Author: Caissy/Muellerschoen

To the RTWG:  October 6, 2003

Dear Colleagues,

We are pleased to announce that a web site has been established where you
can view a demonstration of data flow within an IGS Real-time Network
prototype. The prototype represents a major step towards a real-time
infrastructure for the IGS and is a demonstration of the architecture we
agreed to in Ottawa for sharing real-time data and in the future real-time
products.  Several elements of the IGS are represented in the prototype
including regional tracking centers, global data centers and analysis
centers.  

Apart from the autonomous real-time networks contributing to the prototype
network, the following applications have been developed to make the
prototype network a reality:

1) An application (udpRelay) which ingests UDP transported data ( any data,
any format ) and relays this data, using the IGS RT protocol, to end users
(analysis centers - or real-time product generation centers).  The plan is
to install and configure these udpRelays at regional tracking
centers/GDC/AC's etc and to route data to end users along a configured path.
One feature of the udpRelay is that it is capable of multicasting any data
being relayed through it, onto the local LAN.  This feature will allow users
of the relay easy access to the real-time data stream facilitating the
development of real-time applications. udpRelays are currently installed at
NRCan, IGN, GFZ and GA (temporarily down as we write this).

2) An application ( MulticastReceive ) that ingests multicast data present
on local LANs.  This application creates obs, eph and met files at a
configurable interval.  This application also creates hourly log
files that are the source of the performance statistics shown at the web
site.

3) An application that illustrates the performance statistics shown at the
web site.  This application relies heavily on RRD Tool and processes the
contents of the log files created by the MulticastReceive application.  

Applications 1 & 2 are running at all relay sites and are available for
Linux distributions ( RedHat 7.3 and higher or SuSE ) as an "rpm"
installation package.  Other Linux distributions have not been tested.  The
udpRelay (app 1) is also available as a Depot file for HP 11.0 or higher.
Solaris 8 or higher can be built on request.  App 2 is only built for
RedHat/SuSE but builds for other UNIX platforms are possible.

Application 3 is running at NRCan where the web pages are hosted.

MOVING FORWARD:  (Preparing for the Berne meeting)

We believe we are now poised to expand the prototype infrastructure into a
managed framework for serious real-time initiatives within the IGS. At this
stage a high priority must be given to increasing the number of stations in
the prototype network towards a critical mass (50+?) of stations. The goal
prior to the IGS Workshop in Berne is a real-time network of 20 - 30
stations.  We are now working directly with ESOC to integrate their
real-time stations and in the near future would like to add additional
stations from agencies that are already contributing.   Most importantly, we
will be extending the opportunity to those of you who have in the past
expressed an interest to contribute but have thus far been left out of the
prototype.  An important focus as we add stations, is the inclusion of
reference frame stations.

We do recommend that all regional operation centers, analysis centers and
global data centers install the udpRelay.  A detailed description of the
udpRelay may be found at
http://igscb.jpl.nasa.gov/projects/rtwg/udpRelay.pdf  A draft user's guide
is also available.  Please contact Mark directly if you would like to
install the relay or if you have other questions pertaining to the relay.  

In preparation for the meeting in Berne we want the group to begin to
actively discuss a number of topics.

--- a) real-time network infrastructure and management. ( Mark / Angie(?) ) 

--- b) real-time data management.  It is important that global data centers
and other agencies, interested or actively involved in real-time / high rate
data management, become actively involved in this topic.  ( Carie(?),
Loic(?) )

--- c) real-time product generation - preparing for this activity.  (Ron &
(?)) 
Topics include: what are the rt-products of the future and what can be done
now in preparation for these products? What product generation activities
can we initiate now as the infrastructure starts to build? What
rt-activities are needed now in aid of existing products? (integrity
monitoring?, linking timing labs?, etc)

Collectively, topics (a&b) are concerned with real-time network operations
and real-time data handling.  For the meeting in Berne we want to 
demonstration our ability to manage a real-time infrastructure (network and
data) and be able to identify the gaps and steps necessary to get to the
threshold of real-time product generation.

Topic (c) is closely tied to (a&b) and therefore the data requirements of
real-time products/activities must be addressed within the context of
network and data operations/management.

If you are interested in any of these topics please initiate or contribute
to the discussion.  If you wish to initiate an activity please share your
interest with the group. 

About the Prototype Network Web Site:

Please keep in mind that this is a work in progress and is subject to
periodic glitches and outages.  The configuration behind the generation of
these web pages is complex and there may be configuration errors. As a
result, some of the station statistics may be incorrect. Configuration
errors will be corrected. 

Most importantly: Use of the information at the web site to assess future
performance of the real-time infrastructure is premature at this time.
  
The web site is being hosted at NRCan.  Because this site is not available
in both of Canada's official languages the site is restricted by username
and password.  

URL: http://igsdr.geod.nrcan.gc.ca/  
Username: operator
Password: 4IGSDR2use

This restriction will be removed in the future so please be patient.

The site will be expanding in the coming days and weeks as additional sites
are added.  The RTWG site at the CB will also be expanding to include
additional information about the prototype and the work of this group.

In closing, we look forward to hearing from you,

Best regards,

Mark Caissy
Ron Muellerschoen,

IGS RTWG Chairs.