LTE EPC
- [Evolved Packet Core - IPLOOK]
- Overview
Evolved Packet Core (EPC) is a framework standardized in 3GPP Release 8 for delivering data and converged voice over 4G LTE-based networks. EPC is based on a persistent network connection or an always-on connection.
EPC helps combine voice and data over an Internet Protocol services architecture. This helps service operators operate and deploy a packet network for 2G, 3G, LTE, WLAN or fixed access such as cable or DSL.
Evolved Packet Core (EPC) is a network architecture that combines access networks like 2G, 3G, and LTE. EPC is a framework for providing converged voice and data services on a 4G Long-Term Evolution (LTE) network.
EPC also offers multiple functionality like:
- Authentication
- Session management
- Setting up bearers
- Application of different Quality of Services (QoS)
EPC and its evolution into the 5G Core (5GC) are central components of 5G architecture.
- The Key Components of EPC
Evolved Packet Core (EPC) is considered a key component in the evolution of service architectures.
EPC is made up of multiple nodes, including:
- Mobility Management Entity (MME): Provides mobility session management, subscriber authentication, roaming, and handovers to other networks.
- Serving Gateway (SGW): Routes user data packets between the UE and the Packet Data Network (PDN). SGW also acts as the anchor point for the UE's IP address and performs mobility management functions.
- Packet Data Network Gateway (PDN-GW): Manages and routes data traffic between the LTE network and external packet data networks, such as the Internet and private corporate networks.
- Home Subscriber Server (HSS): The main subscriber database used within the IP Multimedia Subsystem (IMS). HSS provides details of the subscribers to other entities within the network.
- PDGW (PDN Gateway): The network node that connects the EPC to external IP networks
EPC helps consolidate networks by combining different transport modes such as synchronous and asynchronous transport modes in existing systems. It is a high performance and high capacity network. With an IP-based structure,
EPC can build all possible networks for simplicity. This facilitates simultaneous connections to multiple packet networks and also helps service operators offer more value-added services, such as voice-over-IP calls. It helps facilitate new innovative services, support new applications, and even introduce new business models.
Another advantage associated with EPC is improved network performance with a flat Internet Protocol architecture. This also helps reduce hierarchy between different mobile data elements.
In an LTE network, EPC is a required component for end-to-end Internet Protocol service delivery.
- The Functional Blocks of LTE EPC
The EPC's functional blocks include:
- MME, SGW, and PGW: The main functional interfaces between fixed networks and a PLMN for packet transmission.
- PGW: Acts as the interface between the LTE network and other packet data networks
- S1 interface: Allows each eBN to be connected to the S1 interface of nearby base stations
- X2 interface: Allows each eBN to be connected to the X2 interface for signaling and packet forwarding during handover.
The EPC is the central nervous system of LTE networks. It's responsible for core network functions such as: Data routing, Mobility management, Security, QoS enforcement, Billing.
The EPC represents the Core of an LTE network. It is formed by multiple nodes, the main ones being MME, SGW, PGW and HSS. This nodes offer multiple functionality like mobility management, authentication, session management, setting up bearers and application of different Quality of Services.
[More to come ...]
