WiMAX
Serving Wireless Broadband Access Needs Today
WiMAX
Worldwide interoperability for Microwave Access (WiMAX) is actually the common name for the IEEE 802.16 standards. 802.16 is designed as a high-throughput packet data network radio technology capable of supporting both burst (e.g. web browsing) and isochronous applications (VoIP). WiMAX can offer broadband wireless access at data rates up to 75 Mbit/s per base station up to a distance of 30 miles. The typical speeds may vary depending on location and whether the user is mobile or stationary.
Market Drivers
Worldwide access to Broadband Internet is vital for economic growth and development. Governments worldwide are working to ensure that their nations are able to realize the benefits associated with a strong communications infrastructure. Many countries have already adopted WiMAX as a wireless broadband Internet technology to facilitate rapid economic development. Contributing to this trend is that the move to WiMAX, a technology that is ready for deployment now, is preferable to waiting for alternative technologies that may not be available for a few more years such as 4G LTE.
Benefits of WiMAX Approach
The deployment of WiMAX technology, particularly in developing areas, is based on the difficulties inherent in deploying today's available competing technologies. Wireline technologies are slow and costly to roll out in parts of developed nations. Current cellular network technology can be too costly to use depending on breadth of network coverage, and does not deliver true broadband speed and is simpler to expand since it is an all IP media-centric network. Therefore it is assumed that particularly aggressive WiMAX growth will take place in countries such as Brazil, China, India and Russia; and in regions such as the Americas, Middle East/Africa, Eastern Europe and Developing Asia Pacific.
Technology Requirements
WiMAX Network Architecture
The IEEE 802.16e-2005 standard provides the air interface for WiMAX but does not define the full end-to-end WiMAX network. The WiMAX Forum's Network Working Group (NWG) is responsible for developing the end-to-end network requirements, architecture, and protocols for WiMAX, using IEEE 802.16e-2005 as the air interface.
The WiMAX NWG has developed a network reference model to serve as an architecture framework for WiMAX deployments and to ensure interoperability among various WiMAX equipment and operators.
The network reference model specifies a unified network architecture for supporting fixed, nomadic, and mobile deployments and is based on an IP service model. The simplified illustration above of an IP-based WiMAX network architecture. The overall network may be logically divided into three parts:
- Mobile Stations (MS) used by the end user to access the network.
- The access service network (ASN), which comprises one or more base stations and one or more ASN gateways that form the radio access network at the edge.
- Connectivity service network (CSN), which provides IP connectivity and all the IP core network functions.
The network reference model developed by the WiMAX Forum NWG defines a number of functional entities and interfaces between those entities. Fig below shows some of the more important functional entities.
- Base station (BS): The BS is responsible for providing the air interface to the MS. Additional functions that may be part of the BS are micro mobility management functions, such as handoff triggering and tunnel establishment, radio resource management, QoS policy enforcement, traffic classification, DHCP (Dynamic Host Control Protocol) proxy, key management, session management, and multicast group management.
- Access service network gateway (ASN-GW): The ASN gateway typically acts as a layer 2 traffic aggregation point within an ASN. Additional functions that may be part of the ASN gateway include intra-ASN location management and paging, radio resource management and admission control, caching of subscriber profiles and encryption keys, AAA client functionality, establishment and management of mobility tunnel with base stations, QoS and policy enforcement, foreign agent functionality for mobile IP, and routing to the selected CSN.
- Connectivity service network (CSN): The CSN provides connectivity to the Internet, ASP, other public networks, and corporate networks. The CSN is owned by the NSP and includes AAA servers that support authentication for the devices, users, and specific services. The CSN also provides per user policy management of QoS and security. The CSN is also responsible for IP address management, support for roaming between different NSPs, location management between ASNs, and mobility and roaming between ASNs.
RadiSys ATCA Solution for WiMAX
The commercially proven, ATCA open hardware specification is designed from the ground up to meet the demanding need of evolving networks and video services with service delivery packaging that provides unparalleled scalability, responsiveness, modularity, and flexibility to meet ever increasing telecom network requirements.
Radisys provides Applicaton Read ATCA Platforms for ASN Gateway. RadiSys offers the broadest portfolio of ATCA products that includes switching, x86 based, packet processing and media processing boards with latest silicon technologies to deliver optimal configurations for WiMAX. RadiSys ATCA Application ready platform also includes integrated chassis, OS, diagnostics, system manager, and high availability middleware. This platform can be configured for robust performance in WiMAX for both 10G and 40G technologies.
Below, is a typical configuration one can develop using RadiSys Promentum Platform Elements:
- As a sample configuration, ASN Gateway can be built using RadiSys Promentum 2U/5U/12U ATCA System (includes ATCA-2210 switch), ATCA-7220 Packet Processing Module for functions such as packet forwarding and tunneling, and policy enforcement while ATCA-4500 CPU module may be used for mobility management/IP address allocation, and accounting and charging. ATCA 4.0 — evolution to 40G allows this architecture to smoothly scale to higher performance as network demands grow.
With RadiSys Promentum Platform and family of products, you can deploy modular, flexible, scalable carrier grade ASN Gateway with significantly shorter Time-To-Market.. Learn more about Promentum Application Ready Platforms and building blocks at:
