Intel Network Builders Solution Brief. Intel and ASTRI* Help Mobile Network Operators Support Small Cell Networks

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1 Intel Network Builders Solution Brief Intel and ASTRI* Help Mobile Network Operators Support Small Cell Networks

2 Overview Wireless networks built using small cell base stations are enabling mobile network operators (MNOs) to make more effective use of their wireless spectrum to support new services and provide bandwidth for growing volumes of mobile data. But these small cell networks impact the network core differently than macrocells, driving up signaling volumes to levels that impact performance. Hong Kong Applied Science and Technology Research Institute Company Limited (ASTRI)* has developed virtual small cell gateway and evolved packet core (EPC) systems, leveraging the Intel Open Network Platform Server (ONP Server), to give MNOs a flexible and high performance tool to build out dense small cell networks. Challenge Wireless spectrum for cellular services operates in the ultrahigh frequency (300 MHz-3,000 MHz) band. This band is a critical limited asset for mobile network operators because it is the source of all bandwidth for wireless data services. The more spectrum an MNO has, the more capacity it has to offer faster services to a larger number of users. MNOs are embracing small cells as a strategy to manage spectrum by augmenting existing macrocell-based networks. Small cell is the term for enodeb-compliant base stations that include microcells, picocells, remote radio heads, and others, with a signal radius of up to 2 km. This 1 compares with macrocells that have a signal radius of up to 35 km. Communications service providers are creating heterogeneous networks (HetNets) that combine small cells and macrocells. When they are used in place of a macrocell, small cells leverage spectrum reuse to have a multiplying effect on the amount of spectrum in a given service area. A small cell network segments a serving area, allowing more efficient cell coverage as measured by the increased amount of data from smart devices being transmitted at the same time. According to research by the Small Cell Forum, marks the first time that small cells are moving from carrier trials to large-scale roll outs in MNO networks. It is estimated that tens of millions of small cells will be deployed by U.S. MNOs between now and the end of the decade. By comparison, the 3G network in the U.S. required only 256,000 macrocells. This dense network of small cells will have a significant impact on the core switching elements in a wireless network. The following are some of the key issues raised by this technology transition: Security: To improve coverage, some small cell base stations may be installed in unsecured locations or may be using unsecured backhaul networks. This increases the requirement for data encryption using IKEv2 or IPSec standards. This Crossing the Chasm: Small Cells Industry

3 Signaling and mobility management scalability: The volume and complexity of managing signaling messages between the network and the user equipment (UE), such as handover, paging, S1, and others, increases significantly. Small cell management: The sheer number of small cells means network planning cannot be as comprehensive as with macrocells, leading to overlapping cell coverage and the need for self-organizing network (SON) technology to automatically manage conflicts. These functions are traditionally handled by the evolved packet core (EPC). The EPC has several components that act as the interface between the radio access network (RAN) and the data network. These functions include: Mobility management entity (MME): The MME is the key control-node for the LTE access network. The MME manages session states and authenticates and tracks users across the network. It chooses the serving gateway (SGW) for each user when they come onto the network and again when they move to another node. The MME also terminates signaling required for the mobility of the user s smart device, the signaling required to page a device that is connected but not active, as well as the session management signals that keep the device connected to the IP network. Serving gateway (SGW): The SGW routes and forwards user data packets, while also acting as the mobility anchor for the user when their signal is moving from one base station to another. When mobile devices are idle, the serving gateway initiates the paging process when it detects data (such as an instant message) has arrived for an idle device. 3 Packet data network gateway (PGW): The PGW connects the LTE network to other IP networks and then manages those connections in terms of quality of service and any required deep packet inspection (DPI). The PGW also provides data to the policy and charging rules function (PCRF) to enforce policies and ensure that the users are charged when necessary. The PGW also is the main connectivity point between 3GPP and non-3gpp networks (i.e., WiMAX, 3GPP2 (CDMA 1X and EvDO)). Impact of Small Cells on EPC Aggregating a large number of small cells onto an EPC dramatically increases the signaling volume, which impacts the throughput of the MME. The industry s answer has been the small cell gateway, which was developed to offload the signaling and security requirement from the EPC, while leveraging the rest of the EPC s MME, SGW, and PGW functionality. Solution Hong Kong Applied Science and Technology Research Institute Company Limited (ASTRI) is a leading communications technology provider and operates the largest research and development centers in Hong Kong. The company began its work on LTE technologies in 2008 and has built a leadership position in LTE and LTE Advanced small cell technologies. As part of this work, the company has developed and marketed small cell gateway and EPC systems based on proprietary ATCA-based hardware. Working with Intel, ASTRI has evolved these systems to network functions

4 virtualization (NFV)-based virtual network functions (VNFs) running on Intel x86-based servers. The new NFV-based solutions offer three advantages over the fixed function systems: Reduced capital and operational expenditures: System hardware costs are dramatically reduced when applications run on standard Intel x86 servers2 compared to dedicated, fixed-function hardware. 3 In addition, MNOs can run multiple VNFs on a single server to further improve NFV economics. VNF installation and topology management are also more easily automated using software defined networking (SDN), which can have a significant impact on ongoing operating costs. Rapid innovation: ASTRI can focus on fast time to market for new software functionality because it can leverage open source NFV projects and Intel s CPU innovations. The use of NFV also makes it easier for MNOs to install updated systems in their network, shortening the time from trial to full implementation. Scalability: Scaling the network to accommodate growing demand for data and new services is becoming a critical business challenge for MNOs. With virtualized EPCs and small cell gateways, MNOs can quickly expand their signaling and data capacity as smartphone usage grows. ASTRI Virtualized LTE Small Cell Gateway The NFV version of ASTRI s small cell gateway includes the following components: Figure 1. Functional diagram of ASTRI virtualized LTE small cell gateway 2 Server Configuration for Small Cell Gateway and vepc Performance Claims: Quanta Server with (Compute Node running VNF): 2x Intel Xeon CPU E v2 at 2.80GHz, 64GB Memory, 2x 200G SAS HDD, Intel QuickAssist Adapter 8950, Intel X520 Server Adapter. Wind River* Platform: Wind River Titanium Cloud* patch9. Test completed by Applied Science and Technology Research Institute Company Limited (ASTRI). 3 Example hardware: COTS-based Advanced TCA hardware, which consist of ATCA chassis, ATCA switch blade and processor blades. 4

5 Small cell security gateway (SeGW) for 3G and LTE Networks: This gateway provides outstanding security performance for the network by offering RADIUS-based access authentication and IPSec encryption/decryption for up to 200,000 simultaneous sessions with over 20 Gbps throughput per VNF instance. 2 Small cell gateway: This gateway offloads small cell signaling and mobility management from the EPC for improved overall manageability. The gateway provides S1 interface termination, optimization of paging, and cell-to-cell device handover. The gateway reduces the complexity of the EPC s cell ID management by emulating and aggregating up to 255 small cells as one macro cell to EPC. The gateway supports MME selection, load balancing, and overload handling. Small cell management system (not shown in the diagram): This function is not part of the NFVI, but it is needed to provide system management as well as self-organizing network (SON) and enhanced automatic configuration and optimization of small cell base stations. ASTRI Virtualized Evolved Packet Core (vepc) ASTRI s vepc is a 3GPP-standard compliant VNF. Key components of the system include: Figure 2. Functional diagram of ASTRI vepc 5

6 Mobility management entity (MME): The MME includes complete device mobility and session management functionality, NAS security, authentication, tracking area list management, S1 termination for handover, and paging. The MME also features embedded home subscriber service (HSS) and policy control and charging function (PCRF) for complete policy enforcement and billing data collection. Serving and packet gateways (SGW and PGW): These functions provide mobility anchor and per-user packet filtering and forwarding. With dedicated bearers, the gateways can facilitate special processing rules, such as guaranteed bit rates. The gateways provide accounting and usage records for aggregate maximum bit rate (AMBR) or maximum bit rate (MBR) levels. The SGW and PGW can be combined for small network applications with throughput of up to 20 Gbps2 or can be deployed in separate VNFs. This flexibility allows for the SGW/PGW to be separately deployed into existing LTE networks to expand data capacity. VNFs Built Using Intel Open Network Platform To provide a foundation for rapid development of its vepc and virtualized small cell gateway, ASTRI joined the Intel Network Builders ecosystem and leveraged the open source Intel Open Network Platform Server (ONP Server) reference architecture. 6 The Intel ONP Server reference architecture s software stack includes many of the key open source elements needed to develop optimized SDN/NFV software applications The Intel ONP software stack addresses the integration of multiple open source projects that are required for NFV solutions, including Fedora Linux,* Data Plane Development Kit (DPDK), Open vswitch,* OpenStack,* OpenDaylight,* and others. All of these products are validated on a server platform that includes the latest Intel Xeon processor. Conclusion MNOs are building out their small cell networks and need new core networking solutions that add flexibility, capacity, and network agility to support these networks. ASTRI, working with the Intel ONP Server reference architecture, has developed NFV-based small cell gateways and EPCs that make a difference in these networks.

7 Disclaimers Cost reduction scenarios described are intended as examples of how a given Intel-based product, in the specified circumstances and configurations, may affect future costs and provide cost savings. Circumstances will vary. Intel does not guarantee any costs or cost reduction. Intel technologies features and benefits depend on system configuration and may require enabled hardware, software or service activation. Performance varies depending on system configuration. No computer system can be absolutely secure. Check with your system manufacturer or retailer or learn more at intel.com. Software and workloads used in performance tests may have been optimized for performance only on Intel microprocessors. Performance tests, such as SYSmark and MobileMark, are measured using specific computer systems, components, software, operations and functions. Any change to any of those factors may cause the results to vary. You should consult other information and performance tests to assist you in fully evaluating your contemplated purchases, including the performance of that product when combined with other products. For more complete information visit Intel does not control or audit third-party benchmark data or the web sites referenced in this document. You should visit the referenced web site and confirm whether referenced data are accurate Intel Corporation. Intel, the Intel logo, and Xeon are trademarks of Intel Corporation in the U.S. and/or other countries. *Other names and brands may be claimed as the property of others US