LTE network architecture and functional nodes/elements - Tech | 5G, SDN/NFV & Edge Compute


Saturday, October 17, 2009

LTE network architecture and functional nodes/elements

Source: Ericsson, 2009

The following are the key functional nodes/network elements in the LTE architecture:

Evolved Node B (eNB)
  • eNodeB is the entity that supports air interface and performs radio resource management
  • Provides radio resource management functions such as IP header compression, user data encryption, and routing the user date to the Serving Gateway
  • The radio interface provided by eNodeB can be shared by several operators by having separate MME, SGW & PDN Gateway.
Serving Gateway (SGW)
  • It serves as the mobility anchor for the user plane.
  • It takes care of inter-eNodeB handovers & User Equipment (UE) mobility between 3GPP networks.
  • It is responsible for routing/forwarding data packets between the eNodeB & PDN Gateway
Packet Data Network Gateway (PDN GW)
  • It provides the UE with connectivity to the external packet data networks such as Internet.
  • It serves as the anchor point for intra-3GPP network mobility, as well as mobility between 3GPP and non-3GPP networks.
  • It takes care of Policy and Charging Enforcement Function (PCEF), which includes Quality of Service (QoS), online/offline flow-based charging data generation, deep-packet inspection, and lawful intercept.
Mobility Management Entity (MME) 
  • It manages mobility, UE identities and security parameters
  • It operates in the Control plane and provides functions such as managing session states, authentication, mobility with 3GPP 2G/3G nodes, and roaming.


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  2. its good stuff.. didnt have a clue on LTE but in a few minutes.. am getting to grips with the content.Thanks alot.