Sustainability: The TimeWeb Experience
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The TimeWeb (Time Series Data on the Web) project was a joint project between Biz/ed [1] at the Institute for Learning and Research Technology [2] at the University of Bristol and the JISC/ESRC supported MIMAS service [3] at Manchester Computing at the University of Manchester. The central aim of the project was to develop the key national and international macro-economic time series data banks, such as the OECD Main Economic Indicators, held at MIMAS into a major learning and teaching resource.
The key deliverables of the TimeWeb project were:
The TimeWeb learning and teaching materials and the TimeWeb Explorer were successfully launched into service on Thursday, 14th February 2002 [5]. Through the use of shared style sheets and a common design, movement between the learning and teaching materials developed by Biz/ed and the TimeWeb Explorer Web site developed at MIMAS appeared seamless to the user. Thus Timeweb provided an integrated package of both data and learning and teaching materials.
This case study describes the approaches adopted by Biz/ed and MIMAS to deliver the TimeWeb project deliverables to users and also to embed those deliverables into a service environment to facilitate long term maintenance and support.
In order for the JISC to be successful in its stated aim of enhancing JISC services for learning and teaching, it was imperative that the deliverables from the TimeWeb project were released to users and embedded in a service environment. Both MIMAS and Biz/ed fully understood the importance of releasing the deliverables and promoting their long term use in order to maximise JISC's investment.
In the original project plan, it was intended that the release of prototype interfaces and learning and teaching materials for user testing and evaluation would take place at various stages during the development phase. The objective was that final release of the TimeWeb Explorer and the associated learning and teaching materials would coincide with the end of the project. Once the project ended it was anticipated that the ongoing support and maintenance of the TimeWeb Explorer and learning and teaching materials would be absorbed by the existing MIMAS and Biz/ed service infrastructures.
At the time, these aims were felt to be realistic as both MIMAS and ILRT had considerable experience in transferring project deliverables into services. Whilst MIMAS and Biz/ed successfully achieved the objective of releasing the deliverables into service at the end of the project, the long term support and maintenance has proved more problematic than originally anticipated.
The TimeWeb team encountered a range of problems which had to be overcome in order to achieve the twin objectives of releasing the project deliverables to users and also to embed these deliverables in a service environment to facilitate long term maintenance and support. The following is a summary of the problems encountered and how the Biz/ed and MIMAS teams overcame them:
MIMAS encountered a range of technical problems that needed to be overcome before the TimeWeb Explorer could be officially released to users. To avoid the normal problems associated with the long term support and maintenance of software developed 'in house' MIMAS decided to use a proprietary solution for the development of the Web based interfaces to the time series databanks. The selected solution was SAS AppDev Studio [6] which had been developed by the SAS Institute [7]. The intention was to use the visual programming environment provided by SAS to build a lightweight Java based interface to the time series databanks.
Whilst Java facilitated the development a sophisticated and interactive interface it also resulted in a series of major development problems which had to be resolved. For example, the Java sandbox security model typically does not allow data files to be written to the server or client, an essential step for data downloads. Such development problems were compounded as the TimeWeb Explorer was one of the most advanced projects ever written with SAS AppDev studio, and SAS themselves were limited in the technical help they could provide. The additional staff effort required to resolve the unanticipated technical problems significantly held up development work and prevented MIMAS from releasing the interface for user testing until towards the end of the project. It also resulted in MIMAS shelving plans for the more advanced user interface.
When the TimeWeb Explorer was released for initial user testing a number of unanticipated deployment problems were encountered which caused significant delays. Firstly, the use of the applet required users to install a particular version of the Sun Java Plug-in (Sun's newer releases of the plug-in are unfortunately not backward compatible with earlier versions). AppDev Studio tends to lag behind the latest version of the plug-in produced by Sun and, moreover, different versions of the plug-in could not co-exist on the same PC. This created problems for users unable to install software on their PC due to network restrictions, or for cluster users where the latest version of the plug-in had already been installed. Much work went into finding the best compromise, resulting in a parallel version of Timeweb that ran on later versions of the plug-in also being created. A second deployment problem resulted from the many variations amongst user systems (such as operating system, browser version, download permissions, cache settings or network connection), all of which had some influence on the operation of the TimeWeb Explorer. All these deployment problems had to be fully investigated and documented to allow a wide range of users as possible to use the Timeweb Explorer reliably. Resolution of these technical problems required significant additional development effort towards the end of the project which further delayed the release of the TimeWeb Explorer into service.
Before the TimeWeb Explorer was released to users as a new service, it was necessary to embed it within the existing MIMAS Macro-Economic Time Series Databank Service. As the OECD MEI was updated monthly it was necessary to establish data loading procedures which existing support staff could use. As part of the service integration, it was also necessary to implement and test the access management system required to restrict access to authorised users as required under the terms and conditions of the OECD data redistribution agreement.
It was also necessary to develop a range of support and promotional materials to coincide with the release of the TimeWeb Explorer. MIMAS launched the Explorer alongside an accompanying Web site containing help pages, detailed information on running requirements and links to the metadata for the OECD MEI databank. In addition to email announcements sent out to various lists, a TimeWeb Explorer factcard [8] and an A3 TimeWeb publicity poster were produced and widely distributed. The creation of these publicity materials required assistance from other support staff within MIMAS. In addition, it was also necessary to provide training to MIMAS Helpdesk staff to enable them to deal with initial queries relating to the use of the TimeWeb Explorer.
Having transitioned the TimeWeb Explorer into a supported MIMAS service it soon became apparent that additional effort was required for both on-going maintenance and development of the interface. For example, additional software engineering effort would be required to respond to user feedback/bug reporting and - more importantly - to extend the TimeWeb Explorer interface to provide access to other time series databanks. The loss of dedicated software engineering effort at the end of the project - due to the absence of continuation funding - made the on-going maintenance and development of the interface very problematic.
When the TimeWeb project started in 2000, there were no proprietary systems available that could have been used to provide the required flexible Web-based access to aggregate time series. By the time the project had ended, the Beyond 20/20 Web Data Server (WDS) [9] had emerged as a standard tool for the publication and dissemination of international time series databanks over the Web and was starting to be used by many of the world's largest international and national governmental organisations, such as OECD and the Office for National Statistics (ONS). Not only did the Beyond 20/20 WDS offer the required functionality, it could also be used to import data in a range of different formats. More significantly, the WDS runs in a standard Web browser (IE 4.01/Netscape 4.5 and above) with Javascript enabled thus avoiding the problems associated with Java plug-ins which had been encountered with the TimeWeb Explorer.
In 2002/2003, the MIMAS Macro-economic Time Series Data Service underwent a major transformation as part of the establishment of the new ESRC/JISC funded Economic and Social Data Service (ESDS) [10]. In January 2003, the new ESDS International Data Service [11] based at MIMAS was launched. In order to provide flexible Web-based access to a much larger portfolio of international time series databanks statistics produced by organisations, such as the International Monetary Fund, and to minimise in-house interface development overheads, a strategic decision was taken to standardise on the Beyond 20/02 WDS interface. As a result, an internal project team was set up to plan and oversee the transition from the TimeWeb Explorer to Beyond 20/20 WDS. The project team benefited considerably from the lessons learnt when introducing the TimeWeb Explorer interface into service and the transition to Beyond 20/20 was completed in April 2003.
One of the most significant problems faced in the creation of the learning materials was the sheer breadth of potential data handling skills that exist. There is a wide variety of contexts and qualifications that involve data skills. The Biz/ed team was aware that whilst the Higher Education market was the chief target, the materials would have maximum effectiveness if they addressed other audiences. It follows that supporting the needs of different users is difficult when the user base can be drawn from such a variety of backgrounds.
The main problem faced by the Biz/ed team was in relation to the need for sample data to support the learning and teaching materials under development. This need having been identified, it was necessary to source the datasets and agree terms for their release by the data provider. In this case it was felt appropriate that UK data would be sampled. UK National Statistics were approached in order to gain their approval for a small number of datasets to be held within the TimeWeb suite of learning and teaching materials.
During the period of negotiations with National Statistics there was a change in policy at Governmental level which had the effect of removing all barriers to the use of official data, on the proviso that commercial benefit was not to be obtained. As Biz/ed is a free educational service, this did not pose a problem. However, getting hold of the data codes for the sample datasets added extra delays in being able to finally release the TimeWeb learning and teaching materials.
In preparation for TimeWeb moving into service, it was recognised that the maintenance of up-to-date data was crucial. This involved technical work in creating scripts to run out the data from National Statistics. This occurs on an annual basis. However problems continue to emerge as the codes applied to the data by National Statistics appear to be changed on every update. Thus, on-going maintenance continues to be an issue.
As a non-JISC service at the time of the project, the materials were placed within Biz/ed as a stand-alone resource. Given that Biz/ed became a JISC service in late 2002, there are now issues around the integration of the TimeWeb resource into the service and how they are maintained
One of the key things to come out of the project was how difficult it was to respond to emerging standards and changing requirements both during the development phase and once deliverables have been transferred into a service environment. For example, since the completion of the TimeWeb project, learning objects have emerged as a major theme in e-learning. Migrating the TimeWeb materials to a learning object model and ensuring compliance with new metadata standards (e.g. IEEE LOM) so that that they are reusable and form part of a true resource discovery environment would be a major undertaking which would require additional funding. However, it is very difficult to respond to new funding opportunities, such as X4L [12], when teams and associated expertise have dispersed.
We believe that TimeWeb would have benefited from closer examination of possible project exit strategies at various points during the project. When the project finished in February 2002 there was very little guidance from JISC about future directions. An optimal solution would have been for the project partners - in their roles as service providers - to seek continuation funding for the materials to be updated and the data interface to be maintained. For instance, the sample datasets used within the learning materials could have been adapted to reflect changing interests and events. Whilst we demonstrated successfully that project deliverables could be delivered into service through existing service providers it was clear that additional resources were going to be required for long term support and maintenance. As a project, we should have been more proactive at an earlier stage in terms of making a case to JISC for additional funding.
The detailed planning of the transfer of project deliverables into service was left until towards the end of the project. It would have been better to start the planning at a much earlier stage. It would have also have been advisable to have defined the transfer of deliverables to service as a separate work package in the original project plan. This work package would have needed to be kept under review during the course of the project to reflect changes and developments. However, it was clear from our experience that we had underestimated the amount of software engineering effort required to transfer 'project quality' software to 'service quality'. We also underestimated the amount of additional work that would have to be provided by other support staff to assist with the transfer to service.
Whilst Java held out the promise of developing a sophisticated and interactive interface to time series that would meet the needs of researchers and students alike, we had not fully anticipated the technical problems that would arise. Had we been aware of the pitfalls of the Java route, we would have probably adopted a simpler and more robust database driven approach to delivering time series data across the Web. Rather than trying to fully exploit leading edge technology we should have focused on a less challenging software solution that would have been easier to transfer into service and subsequently maintain.
Whilst the TimeWeb Explorer had a limited service life and was eventually replaced by a commercial system, this does not mean that it was a failure. During the year in service it resulted in a significant increase in the use of the OCED MEI - much of it for teaching and learning. Developing the TimeWeb Explorer gave MIMAS invaluable insights into what was required to deliver international macro-economic time series via an interface that was suitable for both researchers and students. Therefore, TimeWeb has played an important role in the establishment of ESDS International as a major new UK academic data service.
Keith Cole
Deputy Director/Services Manager
MIMAS
Manchester Computing
University of Manchester
Tel: 0161 275 6066
Email: Keith.Cole@man.ac.uk
Andy Hargrave
Biz/ed Research Officer
Institute for Learning and Research Technology
University of Bristol
Tel: 0117 9287124
Email: Andy.Hargrave@bristol.ac.uk
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