# Design and Applications of GLANCE: GLanceable Alarm Notification for a User Centered Experience
## 4 Results of the 2 nd Macro-Phase: Application and Refinement of GLANCE
### Application to a Personal Customizable Notifier
It must be observed that in digital terrestrial television broadcasting networks, transmission malfunctioning may depend on a number of related devices: Fault on one device may provoke faults on other related devices, making it appropriate to provide a clear correlation amongst all faults affecting the same service. Furthermore, processes carried out by a device are somehow \"children\" of previous processes and \"parents\" of processes carried out by successive devices in the chain. It is therefore appropriate to provide a hierarchical visualization of the network status through an \"alarm tree\" that allows operators to easily understand the correlation service/alarm and to quickly identify a malfunctioning final cause (Figure 13 shows a portion of a simple alarm tree on a given service). Since in this case the notifier has to deal with one category only, the basic idea was to visualize a glanceable low-LOD overview of alarmed services (basically adhering to the horizontal scrolling case of GLANCE (Figure 9a)), associated to higher-LOD views allowing for the visualization and exploration of insight data of the service alarms accessible on demand as in GLANCE+. In particular, as illustrated in Figure 14a, the upper bar allows scrolling alerted services either in a user-initiated modality or by automatic cycling, the middle area provides an alarmed service overview along with summary information on device faults of its service components, while the lower bar (initially conceived for generic \"user data\") is used to provide a service-centric network overview. The on-demand panel introduced in GLANCE+ in this case provides details on service alarms visualized either as a list (Figure 14b) or as a browsable alarm tree (Figure 14c). The notifier prototype was implemented as a Java application. Usability evaluations included expert-based methods (cognitive walkthrough) and user-based methods (observational evaluation and verbal protocols [70]). Given that the display was grounded on results achieved and validated by the GLANCE and GLANCE+ projects, in this case the evaluation was more centered on specific application domain goals, efficacy of the novel service-based approach, and alarm data navigability, and for this reason is only sketched here since a more extensive discussion would require to address specific service-oriented fault management issues. In particular, expert-based evaluation pertained general issues about information presentation, information comprehension, and interface interaction, and singled out issues to be investigated by user-based evaluation. The user-based evaluation sessions were conducted in-situ with five experienced PC users, based on a classical user-based schema. Users were recruited among company technical personnel and were potential actual end users of the prototype (\"operators\"), all male, aged between 25 and 40, experts at the application domain. The experimental evaluation was conducted in five distinct sessions (one for each user, each with a duration of about two and a half hours) in the real users' working environment: Users were asked to perform the test during their ordinary job activities (including, e.g., coffee breaks, attendance to other tasks, discussions with colleagues) to test the efficacy of the notifier in the real setting. As discussed  
Figure 14: The GLANCE-inspired “Service in alarm” fault notification display: (**a**) A sample glanceable low-LOD overview of an alarmed service providing summary data (number and severity) on its components and their associated alarms on devices, and a service-centric network overview in term of summary of total services in alarm. Operators can access views with higher LOD by clicking on the small arrow at the bottom of the service overview, like in GLANCE+ an in this case this action discloses a tabbed on-demand panel providing details on service alarms either as a list as in (**b**), or as a browsable alarm tree as in (**c**) (clicks on tree items provide an additional LOD on devices in a balloon fashion).