dynamically learning the security status of a foreign home location register (HLR) or home subscriber server (HSS). 

According to yet another aspect of the subject matter described herein, operating the telecommunications network routing node in the active mode includes using the dynamically learned security of the HLR or HSS to filter traffic from the foreign HLR or HSS. 

A system for dynamically learning and using foreign mobility management node information for telecommunications network security screening includes a telecommunications network routing node including at least one processor and a memory. The system further includes a security database located in the memory. The system further includes a dynamic learning and screening module implemented by the at least one processor for operating in a learn mode in which traffic from foreign mobility management nodes is received and identities of the foreign mobility management nodes are learned and used to populate the security database, operating in a test mode to dynamically learn foreign mobility management node security status and maintaining the security status for the foreign mobility management nodes in the security database, and operating in an active mode to filter traffic from the foreign mobility management nodes using the dynamically learned node identities and security statuses. 

The subject matter described herein can be implemented in software in combination with hardware and/or firmware. For example, the subject matter described herein can be implemented in software executed by a processor. In one exemplary implementation, the subject matter described herein can be implemented using a non-transitory computer readable medium having stored thereon computer executable instructions that when executed by the processor of a computer control the computer to perform steps. Exemplary computer readable media suitable for implementing the subject matter described herein include non-transitory computer-readable media, such as disk memory devices, chip memory devices, programmable logic devices, and application specific integrated circuits. In addition, a computer readable medium that implements the subject matter described herein may 

