Solution Use Cases

LTE 4G Evolved Packed Core

LTE 4G Evolved Packet Core - Cobham Wireless´s LTE 4G technologies are delivering a greater convergence of voice, video and data to subscribers on the move.


Scaling the Evolved Packet Core (EPC) of LTE

LTE/4G technologies are delivering a greater convergence of voice, video and data to subscribers on the move. Convergence coupled with the subscriber’s expectation for always on content, means greater speeds and throughput on a per handset basis. With the ever increasing number of content sources, such as over the top "OTT" multimedia services (RCS - messaging and video calling), service providers are looking to the Evolved Packet Core (EPC) to deliver even more traffic on top of the millions of unique flows currently being serviced, with no impact to existing subscriber service level agreements (SLA).

Per Subscriber SLA Testing for the EPC

Cobham Wireless' test and performance measurement solutions enable emulation of unique subscriber activity on the LTE network with stateful interaction with a range of data, video and packet based voice services. A key benefit of using Cobham's solutions when testing LTE is the ability to analyze the performance on a per subscriber user equipment (UE) or per Link/Interface basis. Cobham's stateful emulation of UEs permits flexible test configurations including unique details of IMSI, TEID and gateway addresses per UE. As the only test solution available with per flow analysis capability, Cobham Wireless enables performance analysis on the unique emulated application traffic flows encapsulated in the individual bearer paths.

In order to achieve the necessary network load conditions required to determine if an individual subscriber SLA is being violated, Cobham Wireless is used to emulate control plane and user plane traffic on the following nodes in the EPC Core:

  • eNodeB: S1-U
  • MME: S11 (to S/P-GW)
  • S11 (to S/P-GW): S5/S8 (to P-GW)

EPC Scalability

Optimization of the LTE network requires that the service provider know the limitations of the EPC. Cobham Wireless’ solutions are highly scalable enabling load testing of the EPC with millions of unique emulated subscriber flows. Cobham’s stateful endpoint emulation permits load testing of both control and user plane, with dedicated performance analysis for session establishment. Verify operational performance of the user plane by testing with a mix of different application traffic flows for each emulated endpoint.

TeraVM functionality is used to test LTE EPC with a number of load conditions:

eNodeB load generation

  • Emulate multiple unique control plane and bearer sessions
  • Load test scenarios of E-UTRAN via eNodeB (S1-U)
  • Analyze per bearer application performance

MME load generation

  • Emulate unique control plane sessions from MME to S-GW
  • Unique tunnel establishment per endpoint
  • Stateful user plane traffic

PDN-GW SGi load generation

  • Emulate S-GW to PDN-GW bearer traffic
  • Emulate backhaul traffic across EPC to SGi (Internet)
  • Analyze per bearer application performance

In addition, use Cobham Wireless for peripheral component testing i.e. load balancing, deep packet inspection (PCEF/PCRF) and service optimization.