srsLTE is a free and open-source LTE software suite.
It includes:
* srsUE - a complete SDR LTE UE application featuring all layers
from PHY to IP
* srsENB - a complete SDR LTE eNodeB application
* srsEPC - a light-weight LTE core network implementation with MME,
HSS and S/P-GW
* a highly modular set of common libraries for PHY, MAC, RLC, PDCP,
RRC, NAS, S1AP and GW layers.

The libraries are highly modular with minimum inter-module or external
dependencies.