In one embodiment, while being connected to the network, a security issue may be detected and associated with the device. The device may be placed on a blacklist for the security issue. The blacklist is a list that is used to deny service for the device when it attempts to connect. Thus, the device is disconnected from the network. Identification information for the device is added to the blacklist at the authentication server. If the device attempts to reconnect to the network, the request is received at the authentication server. The authentication server can then check the blacklist and deny the request for access to the network if the identification information is on the blacklist. This denial is determined without sending the request to the HLR. Accordingly, the HLR is protected in that requests from a device that may be considered a security issue are not sent to the HLR.