Paul Krzyzanowski

An Indoor Wireless System for Personalized Shopping Assistance

By integrating wireless, video, speech and real-time data access technologies, a unique shopping assistant service can be created that personalizes the attention provided to a custorner based on individual needs, without limiting his movement, or causing distractions from others in the shopping center. We have developed this idea into a service based on two products: a very high volume hand-held wireless communications device. the PSA (Personal Shopping Assistant), that the customer owns (or rnay be provided to a customer by the retailer), and a centralized server located in the shopping center to which the custorner communicates using the PSA. The centralized server maintains the customer database. the store database and provides audio/visual responses to inquiries fronr tens to hundreds of customers in real-time over a snrull areo wrteless network.

SWAN: a mobile multimedia wireless network

The SWAN (Seamless Wireless ATM Network) is an experimental indoor wireless network that instigates the combination of wireless access with multimedia networked computing in an indoor setting. It is based on room-sized pico-cells and mobile multimedia endpoints. It enables users carrying multimedia endpoints, such as personal digital assistants (PDAs), laptops, and portable multimedia terminals, to seamlessly roam while accessing multimedia data resident in a backbone wired network. The network model of SWAN consists of base stations connected by a wired asynchronous transfer mode (ATM) backbone network, and wireless ATM last hops to the mobile hosts. SWAN is one of the first systems to realize the concept of a wireless and mobile ATM network. Mobile hosts as well as base stations are embedded with custom-designed ATM adapter cards called FAWN (Flexible Adapter for Wireless Networking). FAWN uses off-the-shelf 2.4 GHz industrial, scientific, and medical (ISM) band radios. After giving an overview of the SWAN network model, and discussing the challenges in making ATM wireless and mobile, the article describes the first phase implementation of SWAN hardware and software. This initial implementation provides connectivity over the wireless last hop. We have investigated both native-mode end-to-end ATM communication across the wired ATM backbone and wireless ATM links, and transmission control protocol (TCP) and user datagram protocol (UDP) communication using Internet protocol (IP) over wireless ATM in the wireless link with IP forwarding and segmentation and reassemble modules at the base stations.

TeleWeb: loosely connected access to the World Wide Web

Abstract The development of the World Wide Web (WWW) has made people reliant on continuous, high-speed, low-cost networks in order to get work done. Ideally, one should be able to browse the Web anytime, anywhere, whether connected to such a network or not. This paper describes the design of TeleWeb, a system we are building to support this goal. We believe that fine-grained cost control is crucial and have developed a “reactive architecture” that supports user-specified adaptation under various operating conditions. There are four key features to TeleWebs architecture: costs are made visible to the user through annotated HTML; budget monitoring warns the user when operations exceed pre-specified limits; actions may be postponed and later triggered when conditions are met; and finally, user customization and system configuration values may automatically adapt according to the changing conditions of use. These mechanisms work together to provide an asynchronous, email-style of browsing in which users can work disconnected from a cache of documents, or trade off communication cost against information needs.

A small domain communications system for personalized shopping assistance

By integrating wireless, video, speech and real-time data access technologies, a unique shopping assistant service can be created that personalizes the attention provided to a customer based on individual needs, without limiting his movement, or causing distractions for others in the shopping center. We have developed this idea into a service based on two products: a very high volume hand-held wireless communications device, the PSA (Personal Shopping Assistant), that the customer owns (or may be provided to a customer by the retailer), and a centralized server located in the shopping center to which the customer communicates using the PSA. The centralized server maintains the customer database, the store database and provides audio/visual responses to inquiries from tens of customers in real-time over a small area wireless network.

Towards a Gigabit IP Router

In this paper we illustrate the application of SWIMs Active Storage Element (ASE) module in constructing high performance IP routers. The logic associated with each ASE is a wide-instruction-word micro-programmable engine, that has been specially designed to efficiently perform operations such as pointer dereferencing, memory indirection, bounds checking, and so forth. This makes it well suited to performing operations such as parsing of the IP header, routing table lookup, checksum computation and exception processing. Our results show that a single ASE running at 20 MHz can process 400,000 packets per second: well over that required to sustain a gigabit router. Multiple ASEs can be used in parallel to achieve even higher processing rates.

SWAN: an indoor wireless ATM network

The SWAN (seamless wireless ATM network) project investigates architectural aspects of networks containing mobile hosts. The network model includes base stations connected via a wired, ATM infrastructure and a wireless, ATM last hop to a number of mobile hosts, ranging in computational and functional abilities from personal digital assistants to notebook computers. The FAWN (flexible adaptor for wireless networking) network interface card was developed as part of the implementation of a small SWAN network. It provides wireless, ATM channels using off-the-shelf FHSS modems which operate in the 2.4 GHz industrial, scientific and medical band, and use a sequence of radio channels of 1 MHz bandwidth to provide up to 625 kb/s raw bit rate. The first phase of the implementation has been completed and provides basic wireless ATM connectivity. This paper presents an overview of the SWAN network, followed by a description of the implementation which has been built to validate our initial architectural design.

A testbed for mobile networked computing

The rapid deployment of wireless access technology, along with the emergence of high speed integrated service networks, promises to provide users with ubiquitous access to multimedia information in the near future. We are building an experimental testbed system, SWAN (Seamless Wireless ATM Network), to mimic this emerging networking environment. Our wireless access network is organized according to a nanocellular design with base stations serving as a gateway for communication between the wired network and the mobile hosts in a cell. Normally, a mobile host sends and receives traffic through the base station in its current cell. But SWAN also supports direct ephemeral networking between a limited number of cooperating mobile hosts within a small domain. The heart of the testbed is a networking subsystem, FAWN (Flexible Adapter for Wireless Networking) that interfaces the standard PCMCIA bus to an RF modem. The FAWN interface is used with a PC or workstation connected to a wired backbone network or a portable device such as a laptop or palmtop computer. In addition, a user interface consisting of an LCD display, audio I/O, and a bar code reader has been built. When interfaced with FAWN this results in a portable wireless multimedia terminal.

Design of an active memory system for network applications

We describe an active memory named SWIM (Structured Wafer-based Intelligent Memory), designed for efficient storage and manipulation of data structures. The key architectural idea in SWIM is to put some processing logic inside each memory chip that allows it to perform data manipulation operations locally and to interact with a disk or a communication line through a backend port. A network or I/O subsystem is built using an interconnected ensemble of such memory logic pairs. A complex network processing task can now be distributed between a large number of small memory processors each doing a sub-task, while still retaining a transparent memory interface. We argue that active memory based processing enables more powerful, scalable and robust designs for storage and communications subsystems, that can support emerging network services, multimedia workstations and wireless PCS systems. A complete parallel hardware and software system constructed using an array of SWIM elements has been operational for over a year.<<ETX>>

A VC-based API for renegotiable QoS in wireless ATM networks

Quality of service (QoS) support for multimedia applications has been widely discussed in the context of high speed wired networks. As interest increases in wireless ATM networks that extend the connection to a wireless endpoint, the issue of QoS over a wireless link has to be addressed. We focus on the provision of QoS at the application level in a wireless environment. Our work includes the design of an application programming interface (API) that allows applications to specify and renegotiate the QoS level during a call; as well as the implementation of such API in a wireless ATM testbed: the SWAN system. Experiments are performed to verify the efficiency of this scheme, and the results reveal quality control for multimedia applications despite changing network conditions.

Hardware-software architecture of the SWAN Wireless ATM network

The SWAN (Seamless Wireless ATM Network) system provides end-to-end ATM connectivity to mobile end-points equipped with RF transceivers for wireless access. Users carrying laptops and multimedia terminals can seamlessly access multimedia data over a backbone wired network while roaming among room-sized cells that are equipped with basestations. The research focus on how to make ATM mobile and wireless distinguishes SWAN from present day mobile-IP based wireless LANs. This paper describes the design and implementation of the ATM-based wireless last-hop, the primary components of which are the air-interface control, the medium access control, and the low-level ATM transport and signalling.The design is made interesting by its interplay with ATM; in particular, by the need to meaningfully extend over the wireless last-hop the service quality guarantees made by the higher level ATM layers. The implementation, on the other hand, is an example of hardware-software co-design and partitioning. A key component of the wireless hop implementation is a custom designed reconfigurable wireless adapter card called FAWN (Flexible Adapter for Wireless Networking) which is used at the mobiles as well as at the basestations. The functionality is partitioned three-way amongst dedicated reconfigurable hardware on FAWN, embedded firmware on FAWN, and device driver software on a host processor. Using an off-the-shelf 625 Kbps per channel radio, several of which can be supported by a single FAWN adapter to provide multiple channels, per-channel unidirectional TCP data throughput of 227 Kbps (or, 454 Kbps bidirectional) and per-channel unidirectional native ATM data throughput of 210 Kbps (or, 420 Kbps bidirectional) have been obtained.