Functionally of EPC in LTE

Functionally of EPC in LTE

• EPC ( Evolved Universal Terrestrial Radio Access Network)
• Functionally the EPC is equivalent to the packet switched domain of the existing 3GPP networks.
• EPC consist of:
  –MME (Mobility Management Entity)
  –SAE GW represents the combination of the two gateways , Serving Gateway(S-GW) and Packet Data Network Gateway (P-GW)
  –Home Subscriber Server (HSS)
  –Policy and Charging Rules Function (PCRF)
• Mobility Management Entity (MME)
  –MME is a controller at each node on the LTE access network. At UE in idle state (idle mode) ,MME is responsible for tracking and paging procedure which includes retransmission therein.
  –MME is responsible for selecting SGW (Serving SAE Gateway) which will be used during initial attach EU and the EU time to do intra-LTE handover.
  –Used for bearer control,a different view R99/4 which is still controlled by the gateway
• Policy and Charging Rules Function (PCRF) – In order to handle QoS as well as control rating and charging, and billing
• Home Subscriber Server (HSS) – For management and security subscriber, combination AUC and HLR
• Serving SAE Gateway (SGW)
• Set the path and forwards the data in the form of packets of each user
• As an anchor / liaison between the UE and the eNBat the time of the inter handover
• As a liaison link between the 3GPP LTE technology with the technology
  (in this case the 2G and 3G)
• Gateway Packet Data Network (PDN GW)
  -Provides for the UE ‘s relationship to the network packet-Provide a link relationship between LTE technology with technology non 3GPP (WiMAX) and 3GPP2 (CDMA 20001X and EVDO)

What Is the Functionality of EPC in LTE?

The EPC (Evolved Packet Core) is the core network in LTE that manages all data and signaling traffic between the user and the internet. It’s responsible for connecting devices to the network, handling user authentication, and ensuring that data is properly routed across the LTE system.

Key Functions of EPC in LTE

• Mobility Management: EPC manages the movement of devices between different cells or even different networks (like from LTE to 3G), ensuring seamless communication as users travel.
• Session Management: It creates, modifies, and terminates data sessions for users, ensuring that data is routed correctly for apps and services.
• User Authentication and Security: EPC verifies the identity of users, authenticates devices, and secures data transmission with encryption to protect user information.
• Traffic Routing: It directs data traffic between the user equipment (UE) and external networks (like the internet or corporate networks), using gateways such as the SGW (Serving Gateway) and PGW (Packet Gateway).
• Quality of Service (QoS): EPC ensures that high-priority services (like voice calls or video streaming) get the bandwidth they need and are delivered with low latency, while lower-priority services use available resources efficiently.

How EPC Works in LTE

When you connect to LTE, your device communicates with the eNB (evolved NodeB), which connects to the EPC. The EPC handles all tasks like managing your connection, routing data to the appropriate destination, ensuring security, and allowing for mobility across cells. It also interacts with external networks, like the internet, to provide the full LTE experience.

Why EPC Matters

The EPC is essential for making sure LTE works as intended. It ensures that you get fast, reliable, and secure connections for everything from browsing to voice calls, even when you’re on the move.