Testing Wireless Core Networks

Transcription

1 Testing Wireless Core Networks QualityAssurer SERIES QA-805/QA-813 Lab-testing tool for comprehensive performance and functionality validation that generates and analyzes a wide range of real-world conditions. KEY FEATURES High-performance and high-capacity VoLTE test solution that supports SRVCC with stateful SIP and RTP media Best-in-class user-plane module that is custom-built for wireless testing applications Powerful traffic-modeling capabilities that enables live network conditions to be accurately reproduced in the lab Conformance, negative, functional, regression and performance testing in a single platform SPEC SHEET SmartReplay feature enables users to quickly introduce new types of application data into the mix Simultaneous VoLTE and user-plane traffic are generated and analyzed for every simulated subscriber with multiple-pdn support Control- and user-plane functionality tightly integrated on single platform enabling real-world test scenarios Scalable, multi-user system with a single control point ensuring that systems can grow effortlessly as requirements grow 2G, 3G, CDMA, LTE and IMS end-to-end testing solution that spans multiple domains from a single high-performance platform Broad coverage of interfaces and protocols with ready-made test packages that cover standard procedures defined in 3GPP specs Mobility testing of intra-lte and irat handovers between LTE and 2G/3G/CDMA and data continuity during mobility across multiple bearers and PDNs Customizable statistics measured in real time that allows users to monitor network performance, compliance and responsiveness under load conditions Realistic MME failover and overload testing scenarios Real-time WiFi offload simulations of both trusted and untrusted WLAN for load testing P-GW over S5, S2a, S2b and SGi Flexible solution that can be easily customized to every unique test environment

2 The CAGR of mobile Internet data is projected to be 66% untill To keep up with this phenomenal growth, network equipment manufacturers (NEMS) are developing innovative products and wireless operators are aggressively deploying long-term evolution (LTE) networks. However, in both of these cases, the first step is to test networks and individual network elements in a lab environment to ensure that they deliver the quality of experience (QoE) that subscribers expect. Lab testing helps to determine optimal network configurations prior to deployment, thus reducing CAPEX. Remember, the cost of finding a problem in the field is significantly higher than the cost of finding it in the lab. EXFO s wireless core testing (WCT) application is the industry s leading lab-testing tool for comprehensive performance and functionality validation. When integrated into EXFO s purpose-built QualityAssurer platform, this application simulates over 10M subscribers, generating and analyzing up to signaling messages per second, or 130 Gbit/s of user-plane data. In addition, it handles a wide range real-world testing conditions, from individual elements all the way to multidomain (2G/3G/CDMA/LTE) end-to-end testing. NEW CHALLENGES LTE has been designated by 3GPP as the next-generation mobile architecture that will effectively meet the growing demand for broadband, which is triggered by the voracious consumption of data-hungry applications on smartphones and tablets. The flattened, all-ip architecture and the specific performance targets of LTE present new challenges for EPC network element testing: 1. EPC elements must be able to handle increasing levels of signaling and user-plane loads under strict latency requirements. Network elements must be tested and benchmarked under realworld load conditions. 2. Quality of service (QoS) is a cornerstone of LTE and should be tested under specific user-plane traffic patterns and load conditions seen in live networks. 3. VoLTE services are being introduced to compete with OTT applications. Testing these services is critical because their quality and reliability is what sets them apart from OTT applications. 4. LTE has introduced specifications, such as guaranteed bit rate (GBR) and max bit rate (MBR), to effectively manage user data. The implementation of these concepts should be targeted for testing. OVERCOMING THE CHALLENGES 5. LTE networks will typically be implemented over legacy networks (2G/3G/CDMA), which means that they must integrate seamlessly as subscribers move across them. These inter-rat scenarios must be thoroughly tested, because interdomain procedures are complex and can lead to dropped sessions or other disruptions. 6. Increasingly, LTE and 3G elements are being combined on the same platform, creating a unique set of testing challenges. 7. One of the challenges of testing the wireless core is the large number of interfaces involved. Besides capacity and performance, test tools must be able to simulate a high number of interfaces and associated elements. When deployed on the QualityAssurer platform, the WCT application provides: Complete wrap-around testing of the system under test (SUT), whether it is one element or any combination of elements spanning multiple domains. Integrated control-/user-plane testing powered by purpose-built hardware resources. The simulation of millions of subscribers and thousands of network elements. Traffic patterns and loads mimicking live networks, on both the control and user planes. Extensive and customizable statistics for an accurate view of the SUT s performance. Typical testing scenarios are described on the next page, but test configurations are not limited to these examples.

3 VoLTE TESTING Wireless Core Networks Test Solution Thousands of enbs and millions of subscribers can be simulated to recreate live network volume and scale. Simulated subscribers behavior can be modeled to reflect behavior of actual subscribers in a live network. The combined behavior of all subscribers results in predictable traffic patterns in a network, both on the control and user planes. With EXFO s QualityAssurer, users can easily configure the system to generate these traffic patterns. On the control plane users can: Input the BHCA associated with different types of procedures. This captures the traffic patterns that emerge from the aggregation of behavior of millions of subscribers Configure specific sequence of procedures to be executed by groups of subscribers. This models traffic associated with special events and venues Similarly, on the user plane side, diverse subscriber behavior results in predictable patterns of traffic in the network. This manifests in user plane traffic distribution patterns across: Different types of application data (ftp, http, video streaming, VoLTE, etc.) Different bearer types (default, dedicated, GBR, non-gbr) Different QoS requirements, mapped to QCI (QoS class identifier) values With the QualityAssurer solution, users are able to specify the user-plane mix to be generated based on the above parameters. User-plane data generated based on user input can drive 1GE and 10GE links at line rate. Every single VoLTE call and data session of this generated data can also be analyzed in real time to verify: End-to-end performance of the network Voice quality measurements using R factor and MOS Proper prioritization of data by network based on QCI Correct enforcement by network of key policies such as: GBR MBR Packet loss Latency Although the focus is on testing VoLTE, it is important to also test other types of application data in order to reflect live network reality. The fact that VoLTE shares the same network resources with other applications implies that these other data types have an impact on VoLTE performance, and vice versa. It is important to measure this impact to ensure that it is within acceptable limits. See the use case described below for an example. If desired, it is possible to test with VoLTE traffic only. Subscriber behavior is just one aspect of the diversity that is seen in real networks. Some other things that contribute to this diversity are: Variations in behavior of network elements from different vendors. This typically results from slight variations in the interpretation of specifications The constant introduction of new types of applications and the data generated by them The behavior of applications on smartphones and other devices resulting in network traffic (often bursty) being generated even without any explicit action on the user s part New applications in the machine-to-machine (M2M) and Internet of Things (IoT) space To be able to accurately replicate all of this diversity in the lab requires tremendous flexibility on the part of the test tool. The QualityAssurer solution provides this flexibility: Easy-to-use graphical editors that enable users to quickly incorporate any variations to message templates and call flows (both control and user plane) SmartReplay feature that allows new types of application data to be quickly incorporated into the generated traffic mix. All it takes is a capture of one session of the desired new application

4 The testing needs not be limited only to intra-lte scenarios. It can also include irat mobility scenarios to 2G/3G networks. This can be accomplished by having the QualityAssurer simulate the necessary 2G/3G elements: MSC for Sv & I2 interfaces needed for SRVCC SGSN for S3 and S4 interfaces for handover of data sessions RNC for S12 interface Some of, but not limited to, the test scenarios provided by EXFO VoLTE test solution are: End-to-end EPC and IMS testing End-to-end wireless core and IMS testing including irat to 2G/3G Gateway testing Policy and charging control (PCC) Figure 1. EPC end-to-end testing MME TESTING IN ISOLATION The WCT application can simulate as many of the following elements as needed: UE, enodeb, SGW, HSS, MME, SGSN, MSC, EIR, HRPD, IWS, SMLC/GMLC, MBMS GW and CBC. The MME can therefore be completely surrounded by simulated elements, enabling the comprehensive load-testing of basic functionalities as well as advanced features. Each module can simulate up to one million subscribers. However, for HSS simulation, this number can be increased to over two million. Furthermore, up to 4000 enbs can be simulated from a single blade. WCT allows users to subject the SUT to traffic patterns that mimic real-world conditions as well as test: Network element capacity and functionality, both in isolation and in combination Wireless core capacity and functionality, including EPC and 2G/3G/CDMA Network element interoperability with third-party vendors Control and user planes in a cohesive manner QoS through gateways, especially under heavy load conditions Different types of mobility events, both for intra-lte and irat mobility

5 Since the application can determine the exact network capacity required prior to deployment, users will avoid purchasing superfluous capacity or falling short. The Call Profiling feature adds busy hour call attempts (BHCA) to different procedures, sending traffic that reflects patterns seen or anticipated in live networks toward the MME. Other traffic patterns can be simulated, such as morning commute, lunch hour, evening rush hour, as well as special events like concerts, sporting events and emergencies. S1 MME pool feature ensures that load distribution across MMEs in a pool in case of failures and overload condition are handled correctly. When a serving MME goes down, enb selects a new MME from the pool that has been established earlier based on the weight factor. When a MME is overloaded, a load balancing tracking area update (TAU) is issued to the targeting UEs and these UEs will then be transferred to a new MME. The MME can also be tested for: Ciphering and integrity protection Intra-LTE and irat mobility Location services Network-assisted cell changes (NACC) Broadcast services MBMS Emergency calls Reliability Multi-homing Figure 2. The complexity of MME testing

6 SGW TESTING IN ISOLATION The WCT application can simulate any of the following elements: UE, enodeb, PDN-GW, MME, SGSN, PCRF, HSGW and RNC. Testing the SGW requires generating traffic over both control and user planes. The control- and user-plane data must be tightly coupled in order to simulate realistic subscriber and network behavior. Using the state-of-the-art W 2 CM userplane module housed in the QualityAssurer platform, the WCT application can generate and analyze real-world, layer-7 application data in both 1 GigE and 10 GigE interfaces. A perfect mix of user-plane data can also be generated according to data type (FTP, HTTP, video, etc.), bearers (default, dedicated, GBR, non-gbr, etc.) and other relevant parameters. The SmartReplay feature of the W 2 CM module can capture a single session of an application and replicate it millions of times over, allowing the desired user-plane traffic load to be generated toward the SGW. The Call Profiling feature can generate realistic traffic patterns that not only cover LTE functionality but also interactions between LTE and legacy networks. PDN-GW TESTING IN ISOLATION The WCT application can simulate any of the following elements as needed: SGW, CGW, PCRF, OCS, HSGW and PDN. One of the key features of a PDN-GW is deep packet inspection (DPI), which adds value to user data through preferential treatment depending on type, source, etc. This is done for security purposes (e.g., detecting DoS attacks) as well as to ensure the smooth operation of the network (e.g., throttling undesirable data like P2P). The proper handling of data by the PDN-GW is also critical to delivering the highest QoS to operator services like VoLTE. Effectively testing these user-plane, dataprocessing capabilities requires generating different types of pertinent data at high throughputs. The W 2 CM module is designed for this, especially for wireless testing, and is the industry s leading user-plane testing solution both in terms of performance and functionality. Figure 3. SGW testing covering control and user planes Figure 4. PDN-GW testing covering control and user planes

7 MME AND SGSN COMBO TESTING The WCT application can simulate any of the following elements: UE, enodeb, SGW, HSS, MME, SGSN, MSC, EIR, HRPD, IWS, SMLC/ GMLC, MBMS GW, CBC, RNC, BSC, GGSN, HLR, SCF and SMS-GMSC. Increasingly, NEMs are bundling LTE elements and 3G elements together on the same platform. This also benefits operators as it is a cost-effective upgrade path from 3G to LTE that optimizes the interoperability between both domains. One of the most popular combinations is MME and SGSN. Powered by the QualityAssurer platform, the WCT application can simulate 2G/3G as well as LTE elements to test this combination. The cutting-edge user-plane functionality of the W 2 CM module can also be used to test this aspect of the SGSN. Real-world traffic models can be simulated across both control and user planes, including mobility scenarios between 2G/3G and LTE. END-TO-END EPC TESTING The WCT application can simulate any of the following elements: UE, enodeb, SGW, HSS, MME, SGSN, MSC, EIR, HRPD, IWS, SMLC/ GMLC, MBMS GW, CBC, RNC, PCRF, OCS, CGW, HSGW and PDN. This planning test must be executed prior to deploying a live network because it will validate and qualify the capacity and service-delivery capabilities of the entire EPC across both the control and user planes. This test not only ensures that the system is functioning properly, it ensures that the system is scaled correctly to meet the expected traffic load. VoLTE is a key feature for operators and the endto-end test configuration is the perfect setup to validate it. All the elements within the EPC must perform optimally for the end user to obtain the desired quality of experience. Figure 5. Combo-element testing covering 3G and 4G Figure 6. EPC end-to-end testing

8 FULL TESTING RANGE Wireless Core Networks Test Solution In addition to the typical use cases described herein, the WCT application can test many other network elements in the wireless core (e.g.: GGSN, HSS, PCRF, etc.) in isolation or in combination with other elements. Although the QualityAssurer platform is geared towards performance testing, the WCT application is capable of handling the full testing lifecycle: conformance, negative, functional, regression and performance. One of the key differentiators is the level of flexibility provided by the application. This enables practically any test scenario to be implemented, even by the end user. The ability to execute batch tests, filtered according to the user s selection criteria, enables effective conformance and functional testing. The following diagram illustrates one example of the type of complex test configurations that are possible with the WCT. Figure 7. Multidomain end-to-end testing across 4G/3G/2G/CDMA

9 TECHNICAL SPECIFICATIONS QualityAssurer ATCA-based chassis System controller, shelf manager and 500GB HDD included Can be daisy-chained to scale as needed Two models available: QA slot platform that holds up to five processor blades 19 inch, rack-mount 7U system Weight: 25.5 kg AC power: 90 V to 250 V QA slot chassis that holds up to 13 processor blades 9 inch, rack-mount 13U system Weight: 29 kg DC power: 48V PEv2 Processor blade dedicated to control plane Single-slot ATCA blade Dual 8-Core Intel Xeon Processor E5-2648L at 1.8 GHz (32 threads in total) 64GB RAM or 128GB RAM Up to 2.25 million simulated UEs per blade simulated enbs per blade messages/s on S1-MME messages/s on GTP-C-based interfaces, including S10, S11, S messages/s on S6a with 5 million subscribers W 2 CM User-plane blade based on FPGA technology Two 10 GigE ports and eight 1 GigE ports Line rate, layer-7 application data generation and analysis on all eight 1 GigE ports or one 10 GigE port, or line rate on both 10 GigE ports 2 million total bearers per 10 GigE port 1 million active bearers per 10 GigE port W 2 CM Lite User-plane blade based on FPGA technology Two 10 GigE ports and eight 1 GigE ports Line rate, layer-7 application data generation and analysis on all eight 1 GigE ports or on one 10 GigE port 2 million total bearers per 10 GigE port 1 million active bearers per 10 G port

10 INTERFACES AND STANDARDS S1-AP: 3GPP TS v8.2.0 (R8-Jun08), v8.3.0 (R8-Sept08), v8.4.0 (R8-Dec08), v8.5.1 (R8-Mar09), v8.6.0 (R8-Jun09), v8.7.0 (R8-Sep09), v8.8.0 (R8-Dec09), v (R8-Jun10), v9.2.0 (R9-Mar10), v9.4.0 (R9-Sep10), v9.5.1 (R9-Jan11), v9.6.0 (R9-Apr11), v (R10-Dec11), v11.6.0, v S1 Signaling Transport: 3GPP TS v8.0.0 (R8-Dec07) S1 Data Transport: 3GPP TS v8.0.0 (R8-Dec07), v8.1.0 (R8-Mar08) NAS: 3GPP TS v0.3.0 (Jun08), v1.0.0 (R1-Sep08), v8.0.0 (R8-Dec08), v8.1.0 (R8-Mar09), v8.2.1 (R8-Jun09), v8.3.0 (R8-Sep09), v8.4.0 (R8-Dec09), v8.7.0 (R8- Sep10), v9.2.0 (R9-Mar10), v9.4.0 (R9-Sep10), v9.5.0 (R9-Dec10), v9.6.0 (R9-Mar11), v (R10-Dec11), v11.9.0, E-UTRAN Architecture 3GPP TS v8.2.0 (R8-Jun08), v8.4.0 (R8-Dec08), v8.5.0 (R8-Mar09) EPS Architecture 3GPP TS v0.6.2 (R0-Mar08) S6a: 3GPP TS v1.1.0 (Jul08) with IETF RFC3588, v8.2.0 (R8-Mar09), v8.3.0 (R8-Jun09), v8.4.0 (R8-Sep09), v8.5.0 (R8-Dec09), v8.8.0 (R8-Sep10), v9.2.0 (R9- Mar10), v9.4.0 (R9-Sep10), v9.5.0 (R9-Dec10), v9.6.0 (R9-Apr11), v (R10-Dec11), v11.8.0, v S10/S11: GTP TS v0.6.2 (Mar 08), v0.9.0 (Jul08), v9.5.0 (R9 Dec10), v (R10-Dec11) S5: GTP-C 3GPP TS v9.3.0 (R9-Jun10), v (R10-Dec11) GTP-C: 3GPP TS v8.0.0 (R8-Dec08), v8.1.0 (R8-Mar09), v8.2.0 (R8-Jun09), v8.3.0 (R8-Sept09), v8.4.0 (R8-Dec09), v9.2.0 (R9-Mar10), v9.3.0 (R9-Jun10), v9.4.0 (R9-Sept10), v9.5.0 (R9-Dec10), v9.6.0 (R9-Apr11), v (R10-Dec11), v11.8.0, v GTP-C 3GPP TS v (R7-Dec09), v (R8-Dec10), v11.8.0, v PMIPv6: 3GPP TS v8.1.0 (R8-Dec08), v8.2.0 (R8-Mar09), v8.3.0 (R8-Jun09), v8.5.0 (R8-Dec09), v9.2.0 (R9-Jun10) SGs: 3GPP TS v8.4.0 (R8-Dec09), v8.7.0 (R8-Sep10), v9.1.0 (R9-Mar10), v9.3.0 (R9-Sept10), v (R10-Dec11), v11.8.0, v SMS: 3GPP TS v9.0.1 (R9-Mar10), v (R10-Dec11), v SMS GSM: 3GPP TS v8.6.0 (R8-Mar09), v9.2.0 (R9-Mar10), v9.3.0 (R9- Sept10), v (R10-Apr11), v11.5.0, S3: 3GPP TS v8.8.0 (R8-Dec09), v9.2.0 (R9-Mar10), v9.4.0 (R9-Sept10), v9.5.0 (R9- Dec10), v9.6.0 (R9-Mar11), v (R10-Dec11) S4: 3GPP TS v8.8.0 (R8-Dec09), v9.3.0 (R9-Jun10), v9.7.0 (R9-Dec10), v (R10-Dec11) SLs: 3GPP TS v9.2.0 (R9-Sept10), v (R10-Dec11), v11.3.0, v SLg: 3GPP TS v9.2.0 (R9-Sept10), v (R10-Dec11), v11.1.0, v S101: 3GPP TS v9.2.0 (R9-Apr10), v9.4.0 (R9-Sep10), v (R10-Dec11) S102: 3GPP TS v9.2.0 (R9-Jun10), v (R10-Dec11), v11.1.0, v SBc: 3GPP TS v (R10-Dec11) Sv: 3GPP TS v9.6.0 (R9-Apr11), v (R10-Dec11), v11.5.0, v S13: 3GPP TS v8.8.0 (R8-Sept10), v9.2.0 (R9-Mar10), v9.4.0 (R9-Sept10), v9.6.0 (R9-Apr11), v (R10-Dec11) Sm: 3GPP TS v9.5.0 (R9-Jun10), v (R10-Dec11) Gx/Gxc: 3GPP TS v8.3.0 (R8-Mar09), v8.4.0 (R8-Jun09), v8.6.0 (R8-Dec09), v9.3.0 (R9-Jun10) Gxa: 3GPP TS v9.5.0 (R9-Jan11) 3GPP TS v9.3.0 (R9-Jun10) Ga/Gz: 3GPP TS v8.1.0 (R8-Sept09), v9.0.0 (R9-Jun10) Gy: 3GPP TS v8.6.0 (R8-Mar09), v8.9.0 (R8-Dec09) v (R8-Jun10) Ge: 3GPP TS v9.2.0 (R9-Dec10) Gd: 3GPP TS v9.4.0 (R9-Dec10) 3GPP TS v GPP TS v3.7.0, v GPP TS v GPP TS v5.0.0, v GPP TS v GPP TS v5.5.0, v5.8.0, v GPP TS v5.1.0, v6.4.0 RIM 3GPP TS v9.4.0, v Gr: 3GPP TS v9.4.0 LPP: 3GPP TS v11.5.0, v GTP: 3GPP TS v8.3.0, v9.5.0 GTPv1: 3GPP TS v8.2.0 GTPv2: 3GPP TS v8.0.0 DIAMETER Rx 3GPP TS v8.7.0 RADIUS SGI RFC 2865 and 2866 RADIUS 3GPP TS v8.4.0 ASN.1 encoding rules: ITU-T X.691 IPv4 IETF RFC791 IPv6 IETF RFC 3513 TCP IETF RFC 739, Len 16 UDP IETF RFC768 (3309) HRPD: 3GPP2 CS v20 CDMA2000 1x 3GPP2 CS0097 v12 S2a: 3GPP TS v9.4.0 RANAP: 3GPP TS v9.5.0 GMM: 3GPP TS v9.5.0 IuPS: 3GPP TS v3.14.0, v4.12.0, v5.11.0, v6.7.0, v7.13.0, v8.8.0, v GPP TS v3.12.0, v4.1.0, v6.4.0, v7.9.0, v8.4.0 GB: 3GPP TS v3.14.0, v4.12.0, v5.11.0, v6.7.0, v8.8.0, v9.5.0 Gn/Gi: 3GPP TS v3.9.0, v5.9.0, v6.7.0, v7.9.0, v8.10.0, v GPP TS v4.15.0, v4.3.0, v4.12.0, v5.16.0, v6.7.0, v7.13.0, v9.5.0 LPPa: 3GPP TS v9.1.0, v9.3.0, v9.4.1, v v M3AP: 3GPP TS v920, v10.3.0, v GTP: 3GPP TS v8.7.0, v9.2.0, v9.4.0 GTPv2: 3GPP TS v10.0.0, v GPP TS v8.2.0 ( ), v8.3.0, v8.4.0, v8.5.0, v GPP TS v9.5.0, v9.6.0, v9.7.0, v9.8.0 SCTP IETF RFC 2960, 3309, 3257, 3286, 3758, 4460 E-UTRAN S1-AP: 3GPP TS v SRVCC from E-UTRAN to UTRAN/GERAN: 3GPP TS v GPP2 short message service: 3GPP2 C.S (TIA/EIA-637-A) 3GPP2 short message service over IMS: 3GPP2 X.S EXFO Headquarters > Tel.: Toll-free: (USA and Canada) Fax: EXFO serves over 2000 customers in more than 100 countries. To find your local office contact details, please go to EXFO is certified ISO 9001 and attests to the quality of these products. EXFO has made every effort to ensure that the information contained in this specification sheet is accurate. However, we accept no responsibility for any errors or omissions, and we reserve the right to modify design, characteristics and products at any time without obligation. Units of measurement in this document conform to SI standards and practices. In addition, all of EXFO s manufactured products are compliant with the European Union s WEEE directive. For more information, please visit Contact EXFO for prices and availability or to obtain the phone number of your local EXFO distributor. For the most recent version of this spec sheet, please go to the EXFO website at In case of discrepancy, the web version takes precedence over any printed literature. SPWIRELESSCORETESTING.5AN 2016 EXFO Inc. All rights reserved. Printed in Canada 16/10