OdiTek’s Telecom Testing CoE

We have complete set of interface and protocol expertise that can effectively be used in functional and load testing of LTE core network elements. In EPC functional testing area, we can test messages for send or receive of any protocol messages of all the supported interfaces & also can verify IP user plane. In the receiving side, we can verify the EPC solutions that can calculate bit error rate (BER) from the received PRBS sequence. We also possess expertise on BER testing.

Stateful application data can also be generated and verified. In load testing, our LTE EPC expertise can test heavy loads of control-plane and user-plane traffic test scenarios. We can also comprehensively test security protocols, support for IPSec, authentication algorithm, NAS ciphering/integrity and other advanced features.

Wrap-around testing in LTE EPC

We have long experience of doing wrap-around testing of the core network elements in LTE—MME, S-GW and PDN-GW—either individually or in combination. All the necessary elements and interfaces surrounding the system under test (SUT) can be tested. We may wrap the SUT by using S1-MME, S1-U, S11, S5, S10, S6a, Gx, Gxc, and other interfaces as needed and perform required test cases.

The main topology change in LTE vs. UMTS is the segregation of access control and mobility management in the MME, allowing the SGW and PGW to be dedicated to user traffic routing, management, and charging.

Mobility Management Entity (MME) – network access control, subscriber authentication and UE validation, gateway selection, MME selection, UE paging;

Serving Gateway (SGW) –terminates EPC interface towards the E-UTRAN, user packet routing/forwarding and buffering (downlink traffic is buffered when UE is idle and during mobility), transport-level packet marking (DSCP), accounting per UE and QoS Class Identifier (QCI) for offline charging, mobility anchor for UMTS/LTE mobility, local mobility anchor for inter-E-UTRAN mobility;

Packet Data Network (PDN) Gateway (PGW) – terminates EPC interface towards the PDN, UE IP address anchor, address allocation, user packet routing, packet filtering via DPI, packet screening, DSCP, service-level gating control/rate and policy enforcement, service-level online charging.

Other EPC management elements provide and collect information regarding subscribers, subscriber activity, and network policies:

• Home Subscriber Server (HSS)
• Policy and Charging Rule Function (PCRF)
• Offline Charging System (OFCS)
• Online Charging System (OCS)

LTE EPC Performance testing

• MME testing – S1-MME, S6a, SLs, SLg, and S11 interfaces – control plane performance tests.
• Gateway testing (SGW and PGW) – control plane interfaces, user plane interfaces (S1-U and SGi), and the S5 interface which includes both control and user planes. Test of dynamic policy management (QoS) and charging/credit control, a full test of the data capabilities of the gateways like Gx, Rx, Gy, and Gz interface testing concurrent with S11, S1-U, S5, and SGi testing.