Detection of network transactions or keepalives for maintaining long lived connections are disclosed. A keepalive detector can detect keepalive traffic based on keepalive parameters determined from an analysis of socket level network communication log data that record data transfer events including data sent from mobile applications or clients on a mobile device and data received by the mobile applications or clients on the mobile device, timing characteristics, protocol types, etc. Various statistical analyses can be performed on the network communication data to detect keepalives, taking into account variability in intervals of the data transfer events and sizes of data sent and received on each event. The keepalive detector can also detect keepalives from stream data on a mobile device by analyzing socket level communication messages including timing characteristics and amount of data transferred to detect keepalives and report keepalives using a data structure.