Presentation on theme: "VGISCs view VGISC Uses Cases Geneva October 2005."— Presentation transcript:
VGISCs view VGISC Uses Cases Geneva October 2005
October 20052 V-GISCs view l Metadata and data provision l The FWIS actors exchange metadata and data update to offer a unique view of the available meteorological data, l Metadata and data access -Discovery mode -Request mode -Subscription mode
October 200511 Access Data and Metadata Discovering: browsing a catalogue or launching a request.V-GISC returns a list of datasets with information like data origin, data location, data type Retrieving: Quality of service mechanisms like request cost estimation and queuing mechanisms are used Transfer: The data can either be pushed to the user (subscription) or pulled by the user (direct retrieve).
October 200514 Manage V-GISC An administrator can administrate the cache database An administrator can administrate V-GISC nodes, stop and start them, modify their configuration
October 200515 Monitor V-GISC Each V-GISC node is controlled at a local level Administrators can perform operations similar to the operators ones but they have more privileges to perform deeper operations. They have access to the full software and can change, upgrade, patch the V-GISC nodes
October 200516 Security V-GISC needs to be able to authenticate the users (6.2) and provide an authorization model (6.3) to restrict access to datasets and functionalities of the system.
October 200517 Overview Performance: Where ? l First Tier (Store) Data feed of the VGISC (126.96.36.199 of the requirements) l Second tier (Get) - Access to the data -Data available -Pool of data on a time - Grid Technology - Data base Access l Third Tier (Forward) - Dissemination - Push mode - Pull mode - Shaping of the trafic l Fourth Tier (Remote) - Data feed of the remote application
October 200518 Product Value and Dissemination l Value: Function of 2 parameters -Life expectancy of the product -The value goes down with the time -Elapsed time between 2 productions Ep -Max waiting delay for the product Dpm -Simple rule: Dpm = Ep/2 -Intrinsic value l Performance and Product value are linked l Performance on Third Tier (Forward) - Dissemination - Push mode - Pull mode - Life expectancy of the product -Managed with shaped diffusion channels: network response -Intrinsic value -Managed with priority queuing
October 200519 Shaped Diffusion Channels l MGB Flow Or Shaped Diffusion Channels: - Purpose -For each kind of products -Guarantee a time delay reception - All The global Throughput used as soon a channel runs - All the receivers dont know those channels - Like CIR in Frame Relay l MGB Flow : the concept of MGB flow corresponds to the concept of CIR from the Frame-Relay protocol ; which means that the availability of a minimum bandwidth is guaranteed with the possibility of overload if the network requirements allow it.
October 200520 Example: BPMG Retim2000 Channels on W3A Satellite The product reception delay is garanteed l BPMG1 Alpha: Waiting max delay: 1 minute -Radome: warning messages l BPMG2 Fac: : Waiting max delay 1 minute 30 seconds -Mosaïcs Aspoc, radar + lightning l BPMG3 Alpha: Waiting max delay : 2 minutes -Radome turbo mode + data OPMET et urgent SMT data l BPMG4 Fac: Waiting max delay : 3 minutes -Radar (water cumul) l BPMG5 Fac: Waiting max delay : 5 minutes -Short scale analysis
October 200521 Example: QoS equipment l COTS l QoS equipment has to be set between the data source and the front-end. l It is in charge of traffic shaping l PacketShaper 2000 amongs different equipments : -best performances as it can manage both small / big data files (typically a few 100 bytes – a few 10 Mbytes), low / high data rates (64 kbps – a few 10 Mbps) -Market reference -Can deal with the different types of traffic used in the system : FTP, UDP unicast, UDP multicast, HTTP (and even SMTP, …) -CBR and CIR concepts are both managed -Very good observability (statistics) -Up to date technology to manage QoS : TCP rate control and Queuing combination