End to End Network Reference Model (NRM)
In order to deploy successful and operational commercial systems, there is need for support beyond 802.16e (PHY/MAC) air interface specifications. The end-to-end WiMAX system architecture has been specified by the Network Working Group (NWG) of the WiMAX Forum to address inter-vendor inter-network interoperability for roaming, multi-vendor access networks, and inter-company billing. As part of the overall system architecture, version 1.0 of the Network Reference Model (NRM) has identified functional entities and reference points over which interoperability is achieved between functional entities. The architecture has been developed with the objective of providing unified support of functionality needed in a range of network deployment models and usage scenarios (ranging from fixed - nomadic - portable - simple mobility - to fully mobile subscribers).
The end-to-end architecture based on an All-IP platform is designed to support:
- Voice and multimedia services
- Access to independent Application Service Provider (ASP) networks in an agnostic manner
- Mobile telephony communications using VoIP
- Interfacing with various interworking and media gateways permitting delivery of legacy services over IP (SMS, MMS, WAP etc)
- Delivery of broadcast and multicast services (IPTV)
The Access Service Network (ASN) represents a boundary for functional interoperability with WiMAX clients, WiMAX connectivity service functions and aggregation of functions embodied by different vendors. Connectivity Service Network (CSN) is defined as a set of network functions that provide IP connectivity services to the WiMAX subscribers. A CSN may comprise network elements such as routers, AAA proxy/servers, user databases and gateway devices.
The grouping and distribution of functions into physical devices within a functional entity is an implementation choice; a manufacturer may choose any physical implementation of functions, either individually or in combination, as long as the implementation meets the functional and interoperability requirements. PacketMAX has performed stringent interoperability testing with leading 802.16e ASN/CSN developers to ensure robust and transparent service delivery to users of mobile wireless broadband.