NCES is a Grid Service
estimating the cost of grid network action. This cost is an input for
grid middleware optimisers, like EDG Replica Optimisation Service, to
determine optimal data file or service to access.
NCES is built above Network Monitoring Infrastructure which provides
periodic measurements of basic network metrics like available TCP/UDP
bandwidth, UDP/ICMP packet loss and RTT.
Modular architecture of NCES enables to access different network data
storages like RGMA Archiver, SQL Databases, LDAP/MDS and plain files. It
enables also addition of different Network Models to determine the cost
correcponding to the needs of the concrete application.
Architecture:
TBD
Implementation:
V1: JAVA library implementing basic functionality with four data
storage backends:
- RGMAArchiverNetworkCostContext:
For data stored in the RGMAArchiver.
- SQLNetworkCostContext:
For data stored in the SQL database.
- WgetNetworkCostContext:
Data access using HTTP GET command.
- DummyNetworkCostContext:
Used only for testing and development purposes in case there is no
access to the data storage system. It generates random measurements.
This version of NCES has implemented one Cost Model:
- BulkCostModel: Cost model apropriate for bulk data transfers used
by most of the grid applications, like data/database replication
V2: OGSI compliant Grid
Service implementation. Open, configurable, factory based implementation
following OGSA specification.
NCES Service WEB interface
Authors: Robert Harakaly,
Franck Bonnassieux, Pascale Primet
Author contact:
Robert Harakaly
Publications:
- R. Harakaly, F. Bonnassieux, P. Primet: NCES - an Open
Extensible Grid Service for Network Cost Evaluation, in
preperation
- K. Stockinger, H. Stockinger, R. Harakaly, P. Primet, F.
Bonnassieux: Replica
Access Optimisation in a Data Grid Using Network Cost Estimation Service,
submitted to the Journal of Grid Computing
- T. Ferrari, F. Giacomini, R. Harakaly, F. Bonnassieux, P.
Vicat-Blanc Primet: Network
Cost Estimation Service in Grid Computing, submitted to PAM2004
Downloads:
Release v1:
Release v2:
- Service code not yet distributed
- AXIS
client soon
- .NET client (not yet)
Last
updated on November 27th, 2003 by Robert Harakaly