Transcript The GEONETCast Alert Channel and CAP over GTS Simon Elliott EUMETSAT [email protected] Common Alerting Protocol (CAP) Implementation Workshop Geneva, Switzerland, 6-7 April 2011

The GEONETCast Alert Channel
and CAP over GTS
Simon Elliott
EUMETSAT
[email protected]
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Distribution of satellite products
• EUMETSAT operates meteorological satellites
• Satellite data are processed to derive a range of
products (images, radiance data, wind
information, soil moisture, fire detection, etc.)
• Products are produced operationally in near real
time in a variety of formats
BUFR - GRIB - JPEG - ASCII - netCDF - HDF
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Distribution mechanisms
Several mechanisms are used to distribute satellite products
• EUMETCast/GEONETCast
– Satellite DVB-S multi-cast service
– Easy access, many users, almost global coverage
• Global Telecommunication System, GTS
– Global network connecting NMHSs
– Limited access, highly controlled, well established
• Website access
• Archive access
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Volcanic Ash Detection
• Infrared image data from METEOSAT are
processed to detect the presence of volcanic ash
• Products could be:
– GRIB or BUFR encoded for NWP community
– Graphically represented (e.g. JPEG) for Volcanic Ash
Advisory Centre (VAAC) or internet presentation
– Described with a plain text bulletin or in XML
• CAP can be used to encapsulate these formats
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Volcanic Ash on EUMETCast
Style sheet reference
Graphics
CAP
message
Text
CAP message contains
standard information
supplemented by hyperlinks
to associated information
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Sample web page
containing a volcanic
ash CAP message
Display is style sheet
dependent
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
GEONETCast Overview
EUMETCast
Users
FENGYUNCast
Users
EUMETCast
Network
Centre
FENGYUNCast
Network
Centre
Data exchange
EUMETCast
Data
Providers
FENGYUNCast
Data
Providers
GEONETCast
Americas
Network
Centre
GEONETCast
Americas
Data
Providers
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
GEONETCast
Americas
Users
GEONETCast Coverage
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
GEONETCast Alert Channel
• GEONETCast Americas has an alert channel
• EUMETCast is EUMETSAT’s component of
GEONETCast
• EUMETCast currently has a virtual alert channel (part
of product channel)
• In next couple of months dedicated EUMETCast alert
channel will be enabled
• EUMETSAT uses CAP for some of its own products.
The MSG Fire Detection and Volcanic Ash products
are created using CAP
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Channel Based Dissemination
• Each product/product category is assigned to a
dedicated multicast channel on GEONETCast such
as RA-VI BMD,
• Training Channel, Info Channel, Data Channel 1-4
etc. … and “Alert Channel”
• Each channel uses either a dedicated or shared
bandwidth for dissemination
• Priorities are assigned depending on delivery needs
• User groups can be assigned to each channel
(access control supported)
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Dedicated Alert Channel
• Dedicated bandwidth
• Channel is kept free of any other data then alerts
• Channel is setup for high priority and immediate
dissemination
• Data exchange to the partner GNCs
• NRT availability of CAP alerts simultaneously on
the entire footprint
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
GEONETCast Alert Channel
- regular transmission of empty alerts in order to check
the status of the channel
Normal data
ALERT
Provider
CAP Alerts
GEONETCast
Network Centre
Multicast NRT
Dissemination
Portal
(Product Navigator)
e.g. GISC,
DCPC, NC, Others
Data exchange
-High priority
processing and NRT
dissemination on
dedicated channel
-CAP Alert stored in
WEB portal for
Internet retrievals
Partner
Network
Centre
-On reception of a
CAP alert the GNC
decodes the alert to
distinguish if the alert
is for global exchange
or regional
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
High priority NRTDissemination of
CAP Alert Messages
GEONETCast
Users
Reception
Station
GNC
Reference
Reception
Station
Internet
Users
-Recognises incoming
CAP alert file
-Raises alert
- feedback of CAP
alert reception for
SLA monitoring
- can discover and
subscribe to CAP
alerts
The Global Telecommunication
System
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Volcanic Ash on GTS
CAP message in XML is wrapped with routing
information for the GTS. The wrapper is removed after
transfer to the destination to restore the original message.
GTS wrapper
Style sheet reference
Style sheet reference
Style sheet reference
CAP
message
CAP
message
CAP
message
EUMETSAT
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
NWP Centre
Wrapping of CAP for GTS
<?xml version = "1.0" encoding = "UTF-8"?>
<?xml-stylesheet type="text/xsl“ href="cap_alert_eum.xsl"?>
<alert xmlns = "urn:oasis:names:tc:emergency:cap:1.1">
<identifier>EUM.MET09.VASH.1</identifier>
...
</info>
</alert>
<SOH>\r\n\rnnn\r\r\n[ABH]\r\r\n
<?xml version = "1.0" encoding = "UTF-8"?>
<?xml-stylesheet type="text/xsl“ href="cap_alert_eum.xsl"?>
<alert xmlns = "urn:oasis:names:tc:emergency:cap:1.1">
<identifier>EUM.MET09.VASH.1</identifier>
...
</info>
</alert>
\r\r\n<ETX>
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Abbreviated Bulletin Headers for
CAP
ABHs have the form
For volcanic ash data in CAP, this could be:
T1 = X [Common Alerting Protocol (CAP)]
T2 = V [Volcanic ash clouds (SIGMET)] or O [Other]
A1A2 = NT [North Atlantic area, case dependent]
ii = 01 [Essential data as per WMO Resn. 40]
CCCC = EUMG [EUMETSAT/MSG]
YYGGgg = 091345 [date & time, case dependent]
Several choices of T1T2 have been considered, including WV, FX, WX, XW, XO and WO. It is important that the data are
not confused for an existing product. The most recent suggestion, after consultation with, among others, ICAO is T1T2 =
XO.
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011
Conclusion
• The intrinsic standardisation of CAP ensures
syntactic and semantic interoperability of the data
• Dissemination of volcanic ash products using
CAP on the GTS and via
EUMETCast/GEONETCast allows one product to
meet the requirements of different groups of users
• CAP messages can supply the GTS community
with information which can be understood and
used in a variety of applications and disciplines
Common Alerting Protocol (CAP) Implementation Workshop
Geneva, Switzerland, 6-7 April 2011