Coordinating Node Requirements ------------------------------ This list of requirements for Coordinating Node functionality was developed during a brainstorming session at the 20090602 ABQ VDC-TWG meeting. .. todo:: Estimate some times for the unknowns here. * IDs not discoverable until all CNs have confirmed copy * Metadata searches return in max xxx secs * CN can store and search > xxx metadata records * CN can store and search multiple metadata standards - specifically (list Metadata_formats_of_interest.txt) * CN can load-balance to maximize performance * Any xxx CNs can be offline without affecting D1 services * xxx concurrent transactions can be supported - different for different types of transaction e.g. delete vs. insert * Each CN should be available xxx% time * CN should expose MD in search within xxx secs of insert by MN * CN services should be designed to be independently scalable * CN services should be geographically replicated * CN have complete metadata copies from all MNs * D1 should be TRAC and/or DRAMBORA trusted repositories * CN should respect replication policies of MNs * CN should ensure that any given data set is available at any time (subject to policy restrictions) even when xxx% of MNs are offline * CNs must validate that: - data are available at all replicas - replicas are valid * CNs ensure that data are available in current formats (data format upgrade?) * CNs should be economical to run and maintain * CNs should be able to be remotely administered * CNs should be secure and deflect malicious intent * CNs should provide services to detect rogue data (viruses, copyright, )