# AGL VIWI HIGH-VIWI binding architecture This binding is intended to act between low-level binding(s) and clients. It builds ViWi resources as defined in a json configuration file. It implements subscribe/unsubscribe/get verbs for the clients accordingly with protocol specification. Each ViWi resource can be composed of several elements, for which subscriptions will be made to the low-level binding with configurable frequencies or filters. ![ViWi High Level binding architecture](./images/high-level-arch.png) ## Brief VIWI description ViWi (Volkswagen Infotainment Web Interface) protocol defines a serie of objects, which can be queried or updated via JSon messages. Each object is assigned with a unique URI. The depth of the URI tree is limited to 3, i.e. _/service/resource>/element/_, for instance **/car/doors/3901a278-ba17-44d6-9aef-f7ca67c04840**. To retrieve the list of elements for a given resource, one can use the get command, for instance **get /car/doors/**. It is also possible to subscribe to elements or group of elements, for instance **subscribe /car/doors/3901a278-ba17-44d6-9aef-f7ca67c04840**. Requests can also have various filters, or specify a frequency. More details in the [ViWi general documentation](https://www.w3.org/Submission/viwi-protocol/) and in the [ViWi.service.car documentation](https://www.w3.org/Submission/viwi-service-car/)