the subject matter described herein includes methods , systems , and computer readable media for providing a nas node selection function with cn node bearer circuit availability monitoring and availability - based load sharing . according to one aspect , the subject matter described herein includes a method for providing a nas node selection function . the method includes performing various steps at a nas node selection function which may be integrated with or separate from a media gateway . the method includes monitoring bearer circuit availability for each of a plurality of cn nodes . the method further includes storing an indication of bearer circuit availability for each of the cn nodes . the method further includes receiving initial layer 3 messages from radio access nodes in response to mobile station activity . the method further includes , in response to the messages , assigning mobile stations to the mscs in a load - sharing manner using the stored indications of bearer circuit availabilities .