Transport for London, the transportation authority for England’s capital city, recently revamped their rider information services with an open source middleware platform. Application development provider Godel Technologies was tasked with upgrading the city’s information services for commuters and tourists. Some of these systems were decades old and in obvious need of new life. Godel Technologies chose a combination of open source ESB and open source BAM to build a middleware platform that supported the reinvigoration of Transport for London’s transportation service applications.
The system supports both one-off inquiries (a user sends a text with their current location and destination and the system replies with the appropriate transit route) and subscriptions to find out about emerging changes in train schedules (for example, a commuter might sign up to find out ASAP when scheduled maintenance effects their route to work).
The backbone of the new system is built on an open source enterprise service bus (ESB) and the associated open source business activity monitoring (BAM) system from WSO2. According to Simon Bidel, head of professional services at Godel Technologies, using a service-oriented architecture with an ESB to separate all the diverse services has made the system easier and less costly to implement.
For example, Godel Technologies was able to implement an intelligent router service that is able to sort incoming text based on content. The router, in turn, powers an application that allows users to text in alerts about problems such as broken traffic lights. The system is able to route the message to the appropriate channels for maintenance and repair and even to respond to the user with a thank you message. In a company-provided case-study, Bidel is quoted as saying “The traffic light reporting service was built in just two weeks. It proved how quick and easy it was to add a new service, which was one of the primary goals of the SOA.”
In a presentation at WSO2 Con 2011, Simon Bidell recalled, “Someone was asking if BAM was a requirement, or a ‘nice to have’ that we did because we could. In this particular case, it was absolutely a requirement.” He went on to explain the monetization of premium SMS messages and the requirements of accountability to prove and record premium messages.
The BAM system can monitor trends in usage and other areas. For example, the system might show elevated levels of route requests before and after major football matches (that’s soccer for our American friends) when huge crowds of fans, many of whom are unfamiliar with London, are finding their way to or from the stadium.
The BAM system was also found to be useful in detecting and planning for predictable, but unscheduled, usage spikes. It was known that during icy winter weather usage spiked as travelers checked to see how long delays would be and at the same time outgoing messages were scheduled for regular weather alert subscribers. The BAM system allowed Godel Technologies to analyze usage and provide the right amount of bandwidth to ensure that no foreseeable spike in usage would max out the system.