Alistair Urie

An advanced TDMA mobile access system for UMTS

It is now clear that the most successful digital cellular system at present is the European developed TDMA (time division multiple access) based, Global System for Mobiles (GSM) and its DCS-1800 and DCS-1900 derivatives to service European PCN and American PCS concepts, respectively. The GSM system has been designed to evolve, with current standardization work within ETSI addressing a new derivative to service the needs of European railways along with other GSM phase 2+ extensions, such as General Packet Data Service, repeaters, and GSM/DCS roaming, which will keep GSM up to date through to the year 2000 and beyond. But how long can this evolution last? Is GSM the very best possible TDMA-based system? Can it evolve to provide the service needs of third generation mobile? What is the real potential of TDMA techniques? To answer some of these questions, an example TDMA-based radio access system has been developed within the European Advanced TDMA Mobile Access (ATDMA) project, with a specific focus on the terrestrial aspects of the third generation mobile system known in Europe as the Universal Mobile Telecommunication System (UMTS). In this article our baseline assumptions are first described and then a discussion on the transport and control requirements provide details of the ATDMA system concept in terms of the projects overall system model. >

Managing multi-connectivity for IP services

This paper introduces the concept and architecture for access network multi-connectivity (ANMC), an asset that can help to align service provider, application provider, and subscriber imperatives. ANMC can expose available access network and user device-specific information to applications, and thus allow wireless service providers to better manage their network, ensuring that the access option chosen for an application is matched to the needs of the application, given the constraints of the available access connections. Applications benefit from ANMC because with access network knowledge, they may improve the user experience by explicitly adapting their services according to access network constraints or intelligently stage the delivery of services to periods with favorable access connectivity. Since service delivery in the access network can be tailored individually to applications, new business relationships between access network providers and application providers are made possible with inter-system mobility and associated policy control exposed as an application enablement service. The mechanism ANMC uses to support this is intelligent presence, which builds upon techniques defined in 3rd Generation Partnership Project (3GPP) and IEEE 802.21 to support inter-system mobility. Intelligent presence extends the concept of presence from simple reachability, often via a transparent Session Initiation Protocol (SIP) protocol, to richer presence statement dependent on meeting application, service provider policy, network congestion, subscriber subscription, user activity and device state criteria for bearer access.

Using a trusted WLAN network to offload mobile traffic and leverage deployed broadband network gateways

This paper introduces the concept and architecture for the Alcatel-Lucent solution to wireless local area network (WLAN) offload in a case where the WLAN network can be considered as trusted by the home operator of the user. Leveraging up-to-date WLAN access points (APs) that provide both support for strong user equipment (UE) authentication — Universal Subscriber Identity Module (USIM) based- and ciphering (AES-based), WLAN access can offer “trusted” access to the Evolved Packet Core (EPC). This trusted access to the EPC can provide Internet Protocol (IP) address preservation when the terminal moves between 3rd Generation Partnership Project (3GPP) access and WLAN access without requiring the UE to support IPsec tunnels to the EPC or Dual Stack Mobile IP version 6 (DSMIPv6). A WLAN gateway (WLAN-GW) acting as an edge router for the UE is able to get policies from the home operators authorization, authentication, and accounting (AAA) server at UE authentication, and based on these policies, to either send the user traffic to the EPC anchor point — the Packet Data Network Gateway (P-GW) — or to offload such traffic, for example, to the Internet.