EPC - Need and Standardization
Explosion in Data traffic and usage patterns.
Advance in microchip technology.
○ Freedom in choosing a vendor.
○ Market Expansion, cost reduction, increasd benefits.
● 3GPP work on SAE (system architecture
evolution) work item.
● SAE was responsible for EPC (Evolved
Packet Core Network) as an all-IP solution.
● EPC is designed to support high bandwidth
services at high data rates.
EPC - Objectives
● New core network architecture to support high data rate
and reduced latency.
● To support mobility between multiple heterogeneous
access systems (WiMAX, CDMA, 3G, 2G).
● All IP architecture, to enhance the capability of 3GPP
systems to cope with rapid
growths in IP data traffic.
EPC - Major Functions
Authentication and Security.
Policy and Charging Control and QoS.
IP Address Allocation.
EPC - Policy& Charging Control and
Segmented data plans.
Traffic & quota management.
Bill shock prevention.
Personalized alerts and promotions.
● Subscription profile repository.
● contains information such as user specific
policies and data needed for subscriptionbased policies and bearer level charging
rules by the PCRF.
Online Charging System
● Credit management system for prepaid
Offline Charging System
● Receives events from the PCEF and
generates charging data records (CDRs) for
the billing system.
● Offers applications that require the control
of IP bearer resources.
● Communicates with the PCRF to transfer
dynamic service information.
● Enforces gating and QoS for individual IP
flows on the behalf of the PCRF.
● Provides usage measurement to support
● BRAS, BNG, ISG.
● Policy and charging rules function.
● Provides policy control and flow based charging control
● Receives session information from Application function
(AF) over Rx interface, subscription information from
SPR over Sp interface as well as information from the
access network via the Gx.
● Takes all the information and configured operator
policies then creates a service session level policy
decisions which are being enforced by PCEF.