This is the source, either a remote Check Point site or the local SmartCenter, from which the last URL Filtering update was retrieved. An admin checks this when diagnosing a stalled update, since a gateway that should be pulling categorization updates directly from Check Point's cloud but is instead only getting them relayed via SmartCenter, or vice versa, can lag behind depending on how each path is configured. For example, this showing SmartCenter when the admin expected a remote site would explain a longer-than-usual delay in getting the newest category updates.