Metadata Aggregation is the Next Big Thing - Honest!
Posted by nicole on June 9th, 2009
Those of you deeply embroiled in the finer details of federation constructions (no, it’s not just me!) cannot have avoided being in a conversation recently about the need to separate the role of Federations as registrars of metadata and the role of metadata aggregation and distribution.
Simply put, Federations add useful assurance and trust qualities to metadata through registration processes. This is particularly important at the moment in the UK federation, which has been focusing in on commercial content provision via the federated model. However, there are use cases where the geo-centric nature of Federations is not helpful.
We looked at such a case within the REFEDS meeting on Sunday at #tnc2009. All those involved in the REFEDS group need to be able to use federated access to use the REFEDS wiki space and the Kantara wiki space (Kantara is the new Liberty Alliance, watch that space!). It does not make any sense for organisations like Kantara and TERENA to attempt to join all of the Federations involved in REFEDS - even the most lightweight agreements still involve a contract signature process that is difficult to obtain in such organisations.
The solution? A metadata aggregation of all of the entities involved in REFEDS. In this sense, we are talking about a real virtual organisation in operation. John Paschoud rightly queried me on how trust will be maintained within such an arrangement without a Federation. There are various ways of adding trust and assurance to this aggregation. Firstly, the metadata aggregator will come from within the REFEDS group and will only aggregate the metadata of members of the group. In this sense, the virtual organisation itself provides the trust assurances through its operation.
The more interesting point is controlling the way in which Service Providers use the aggregated metadata. Well, in the case of TERENA and Kantara I think we can have a reasonable amount of trust through the status and position of the organisations themselves. For other service providers, the simple approach is to provide ‘terms of use’ for the metadata - akin to an open source software license. Leif has described this approach on several occasions, and it seems very likely now that this will be taken forward. It is the driver behind the new focus of eduGAIN.
The long term impact of this approach will be interesting. In the short-term, I think it will only be used for lightweight applications (such as blogs and wikis) in virtual organisations - in short, the role of the geographically organised federation will not be impacted. In the longer-term, this could put an end to the need for Service Providers to join Federations. Service Provider use of the metadata will be controlled by the metadata ‘terms of use’, negating the need for the providers to join up to membership - they can consume the metadata as long as they follow the terms. It could also affect the concerns that some people have regarding the need for Federations to have strict legal liability cover - I feel that this concern has hindered the progress of interfederation agreements, and of course such a focus will always make Federations more static…and more expensive!
This is a fundamental change to the way that federations might operate in the future. I’ve tried to capture some of this thinking in a presentation…more to follow!