ESM EPS Session Management
The ESM ( EPS Session Management) and EMM (EPS Mobility Management) entity is a control plane function which supports all aspects of signalling for PDN (Packet Data Network) session management, such as EPS Bearer Activation and Modification. In a similar way to UMTS and GPRS , the LTE system includes various ESM messages that setup and manage the EPS bearer. The EPS bearer is similar to the PDP Context found in GPRS and UMTS.
