Sentinel

Sentinel is a Chrome extension that reads Sentinel smartcards for Network Rail’s Sentinel system. It supports verifying cardholders by scanning QR codes or reading card data over NFC, delivering up-to-date information whether online or offline.

Authorized card checkers can authenticate their teams, conduct spot checks, and log TVPs. When online, checks are uploaded to the database; when offline, details are stored locally and synced when connected again.