Sy stem Arc chitectur re

4.2 In ntegration n into GAM MBAS arc chitecture e

The inte ent ‐aware in nterface syst tem require es frequent interactions with other component ts of the GAMBAS S middlewar e. These inte eractions wil ll take place upon well‐d efined interf faces provide ed by the The inte ent ‐aware in nterface syst tem require es frequent interactions with other component ts of the GAMBAS S middlewar e. These inte eractions wil ll take place upon well‐d efined interf faces provide ed by the

F igure 19 – Inte gration of User r ‐Interface Syst tem into GAMB BAS Architectu re

As the fi igure shows, , each mobil e device is e equipped wi th the inten t ‐aware use r interface s system to support interactions s with a mob ile traveller. This require es access to v various sourc ces of data w which are distribut ted in the GA AMBAS syste em. The user r interface sy ystem will co ontact these e sources thr rough the GAMBAS S query pro ocessing sys stem. The q query proce essing system m provides a high lev vel query abstract ion, so that t the access is provided tra ansparently from their a ctual locatio on in the netw work and in a unifo orm manner r.

The data a acquisition n framework k provides pe ersonal data a about a us ser’s activitie es. This data a is made available e on the loc cal semantic data storag ge and can b be accessed directly. It includes info ormation about th he real‐time context of users (e.g. m mode of cur rrent travel) as well as past user tr rips. Data residing at remote parties is accessed th hrough the privacy pre eservation a and data pr rocessing framewo ork in GAMB BAS. Various GAMBAS se ervices are in nvolved in m anaging dat ta that are of f interest to travel llers. The tra ansport netw work provide er offers serv vices to infor rm about the e transport s schedules and real ‐time bus st atus update s. Further, a a GAMBAS ag ggregation s ervice will be e deployed t to collect ridership p histories an nd provides access to fut ture crowd l evel predict ions. Social t travel behav viour, i.e., bus rout tes of a user’ ’s friends, is hosted on th he personal devices of ea ach of the fr riends. There efore, the user inte erface has to o gather this information from the GA AMBAS syste em in a distri ibuted mann ner.

The inte ent ‐aware u ser interface e system us ses both the e one‐time and continu uous queryin ng mode supporte ed by the qu uery process sing system. One‐time q queries are u used to requ uest static d data, e.g., transpor rt schedules. . In contrast, , continuous queries are used to dea al with dynam mic data give en by the The inte ent ‐aware u ser interface e system us ses both the e one‐time and continu uous queryin ng mode supporte ed by the qu uery process sing system. One‐time q queries are u used to requ uest static d data, e.g., transpor rt schedules. . In contrast, , continuous queries are used to dea al with dynam mic data give en by the

As the a above discus ssion shows, , a user will not only re equest remo ote data, but t also make his own travel da ata available e to remote parties. The degree to w which sharin g of persona al data is tol lerated is controlle ed by privacy y policies sto ored in the p rivacy prese rvation fram mework. In or rder to allow w users to make ch hanges to th he sharing p olicy, the us ser interface e will intera ct with the privacy pres servation framewo ork to retrie eve the curre ent privacy setting, visu ualize them and allow th hem to be e edited to enforce his privacy p preferences.