DIVA 4 and EFA 10 - Paradigm Change at the VVS

8 mdv news II/2011
minutes and are then available for the journey
planner. The system has been structured
so that additional AVM systems can be
integrated with relative ease.
Another salient functionality at the VVS is
product presentation, which can be accessed
using EFA10. The presentation products
are separate from the EFA systems at the
VVS. There are two servers allocated for the
presentations where requests are processed
by the load balancer. The process to
generate stop timetables, book pages, stop
area maps and route option maps work without
a DIVA4 database. The Map Server
(responsible for route options and stop
area maps) retrieves the required information
from EFA10 data and the presentation
manager (responsible for stop timetables
and book pages) works with serialized data.
EFA10 provides the same functionality as
EFA9, but is divided into several process
components in order to enable better scalability
for the entire system. Process components
that were added with EFA10 were
originally part of the EFA Location Server
(the Location Server is the EFA search
engine for origin and destination regardless
of form, stop, address, POIs etc.). In the
meantime, they have been relegated more
and more to backend processes for EFA10.
Of note is the EFA PT Kernel split into a process
that only calculates public transport
routes and the EFA Presentation Handler,
which is responsible for timetable presentation.
In addition, the EFA IT Kernel was
also split into a routing process and a GIS
process. Customization, which used to be a
part of the EFA Controller, is now its own
web service. The architecture at the VVS can
be differentiated between http-processes
and backend processes (see figures 11 and
12).
Outlook
The introduction of DIVA 4 at the VVS was a
milestone in the development of DIVA 4. It
was a large and often difficult, but necessary
task. The next step is to integrate
improvements to performance and usability
into the next version. But the door is
now open to further develop the system to
reap the benefits of the new platform. New
topics are timetable management, especially
in collaboration with the Stuttgart
Tram, who is currently transitioning to DIVA
4. One big remaining topic is the use of
multi-tenancy so that other transport authorities
that work with the VVS can be integrated.
Figure 10: EFA journey planner architecture
Figure 11: EFA presentation system architecture
mdv contact for DIVA:
Hannes Gölz
goelz@mentzdv.de
Tel.: +49 (0) 711 615543 - 20
mdv contact for EFA:
Jochen Scholz
scholz@mentzdv.de
Tel.: +49 (0) 89 418 68 - 148