Jussi Lemilainen

Windows NT software design and implementation for a wireless LAN base station

This paper introduces the architecture of a base station designed for a new Wireless Local Area Network (WLAN). The emphasis is on the software but also backgrounds for the design choices made are discussed. The main design objective has been to develop a simple and low-cost system while maintaining suitability for a large variety of applications, ranging from wireless sensors to multimedia workstations. A base station is implemented by attaching a custom WLAN adapter card into a PC. The network adapter consists of a custom wireless Medium Access Control (MAC) protocol and a standard low-power radio subsystem. The PC hosts other wireless network related functions, such as management of a wireless cell and bridging of data between the wireless network and a wired LAN. Currently, a demonstrator network is being implemented. Components implemented for a base station contain the network adapter card, a Windows NT device driver, and a management application that is a user mode program needed for configuring and managing the network interface hardware and the MAC protocol. In addition, a Windows NT protocol driver has been developed for implementing the data exchange between the device driver and the management application.

Implementation of the wireless ATM access terminal

Multimedia applications with audio and video connections have created totally new bandwidth and Quality of Service (QoS) requirements for the computer data networks. In order to meet the new customer requirements also the wireless access networks have to be enhanced to support the increased demand for broadband services. Wireless ATM (WATM) technology has emerged as one of the most promising alternatives for implementing multimedia capable mobile networks. The Magic WAND (Wireless ATM Network Demonstrator) is an international research project designing a WATM network that provides indoor radio coverage and user mobility. The system is mainly targeted for customer premises networks and hot spots with a large number of people within a restricted area, such as airports. This paper describes the architecture of the wireless ATM terminal developed for the Magic WAND demonstrator. The focus is on the terminal software which supports the user mobility and the native ATM access on the Windows NT operating system environment. The first part of the paper presents the generic reference model for the broadband radio networks and describes the Magic WAND system architecture. The latter part of the document focuses on the terminal implementation presenting the structural breakdown of the terminal, the Windows NT operating system and the actual implementation. Finally, the paper depicts briefly the development process and applied design methods.

Architecture for a Windows NT wireless LAN multimedia terminal

The support for multimedia services in wireless access networks is challenging to implement, due to an unreliable and bandwidth-limited wireless medium. In addition, the widely used applications and protocols generally lack the support for quality-of-service (QoS) parameters. This paper presents the architecture of a multimedia wireless LAN terminal. The terminal is implemented using a custom network demonstrator platform connected to a Windows NT workstation. The system provides a separate management plane for configuring the service parameters of a proprietary wireless medium access control (MAC) protocol. Also, native applications that are capable of accessing the MAC QoS parameters directly are supported.