Park from iCloud

The iCloud-initiated parking workflow can be triggered by the user through one of the following 2 methods:

1. Signing into their iCloud account via iCloud.com.
2. Using the Find My application on another device that is logged in with the same Apple ID.

Initiating this workflow will result in the removal of all cards in the Wallet from the specified device.

This section provides an overview of the workflow, including detailed steps, sequence diagrams, and potential error scenarios.

Workflow

Below are the high level steps of the iCloud initiated parking workflow:

1. Card Removal: The user initiates the removal of the cards from his device.
2. Unlink Card: Apple notifies D1 Transit platform that the user wants to remove the transit card from his device. Since it's CBT, a park session is started.
3. Park Card: Apple device connects to D1 Transit platform in order to read the content of the applet instance, so Transit Issuer can save the card state on backend side.

Sequence diagram

Card Removal

The user accesses to his iCloud account, he selects the device and press 'Erase Device'. Wallet will instruct Apple server to delete all cards from that device.

Unlink card

For each card, Apple initiates a managePass API call to D1 Transit platform with the action unlink to indicate the intention to delete the card.

Park card

In CBT ecosystems, the applet instance is not deleted rigth away. Device connects to D1 Transit platform in order to execute commands that can be used for reading and updating applet content.

D1 Transit sends getDigitalCardBundleCommands to Transit Issuer to fetch the commands that shall be returned and executed on device side.

Several round trips may occur to complete the park session.

Once the park session is completed, the applet instance is deleted from the device.

Error Scenarios

Device Offline

As the request is not device-initiated, there is no certainty that the device will be online. In such cases, the request to delete the card may never reach the device. For example, the device may be in airplane mode. Therefore, it is strongly recommended to put the provisioned digital cards to deny list to prevent its use for transit.

Transit Issuer must ensure that the deny list has been fully propagated across all relevant readers before allowing the card to be provisioned on another device. This step is critical to prevent the same transit card from being used concurrently on multiple devices and avoiding potential misuse.