Architecture, Design, Simulation and Performance Evaluation for Implementing ALAX -- The ATM LAN Access Switch Integrating the IEEE 1355 Serial Bus

IEEE 1355 is a serial bus standard for Heterogeneous Inter Connect (HIC) developed for "enabling high-performance, scalable, modular and parallel systems to be built with low system integration cost." However to date, few systems have been built around this standard specification. In this thesis, we propose ALAX -- an internetworking switching device based on IEEE 1355. The aim of the thesis is two-fold. First, we discuss and summarize research works leading to the architecture, design and simulation development for ALAX; we synthesize and analyze relevant data collected from the simulation experiments of the 4- port model of ALAX (i.e., 4-by-4 with four input and output queues) -- these activities were conducted during the 2-year length of the project. Secondly, we expand the original 4-by-4 size of the ALAX simulation model into 8-, 12- and 16-port models and present and interpret the outcomes. Thus, overall we establish a performance assessment of the ALAX switch, and also identify several critical design measurements to support the ALAX prototype implementation. We review progresses made in Local Area Networks (LANs) where traditional software-enabled bridges or routers are being replaced in many instances by hardware-enabled switches to enhance network performance. Within that context, ATM (Asynchronous Transfer Mode) technology emerges as an alternative for the next generation of high-speed LANs. Hence, ALAX incarnates our effective approach to build an ATM-LAN interface using a suitable switching platform. ALAX currently provides the capability to conveniently interconnect legacy Ethernet and ATM- based networks. Its distributed architecture features a multi- processor environment of T9000 transputers with parallel processing capability, a 32-by-32 way non-blocking crossbar fabric (C104 chipset) partitioned into Transport (i.e., Data) and Control planes, and many other modules interlaced with IEEE 1355- based connectors. It also employs existing and emerging protocols such as LANE (LAN Emulation), IEEE 802.3 and SNMP (Simple Network Management Protocol). We provide the component breakdown of the ALAX simulation model based on Optimized Network Engineering Tools (OPNET). The critical parameters for the study are acceptable processor speeds and queuing sizes of shared memory buffer at each switch port. The performance metric used is the end-to-end packet delay. Finally, we end the thesis with conclusive recommendations pertaining to performance and design measurement, and a brief summary of areas for further research study

Report on Selected Standardization Activities of the IEEE BASC and of the ATM Forum

This document describes the standardization activities which were performed during the first year period of the joint project named ﲁ Standardization and Research Project on an ATM/B-ISDN Switching Fabric System that is being jointly performed by Protocol Engineering Center (PEC) of Electronics and Telecommunications Research Institute (ETRI), Institute for Systems Research (ISR) of the University of Maryland at College Park (UMCP) and Modacom Co., Ltd. These standardization activities are related to the IEEE Bus Architecture Standards Committee (BASC) meetings and ATM Forum Meetings. This document also provides the general information about the IEEE Standards meetings and ATM Forum Standards meetings.<P

ATM/LAN Access Switch (ALAX): System Architecture

This document contains the hardware information for the ATM LAN Access Switch (ALAX) that was done as a collaborative research and development effort by the Institute for Systems Research at the University of Maryland, College Park, Protocol Engineering Center in Electronics and Telecommunications Research Institute, and Modacom Co., Ltd. of Korea.<P

OPNET Simulation Model of the ALAX

When this project wsa undertaken, the ALAX system was designed but was not built yet. Because it was too complicated for us to easily predict the detailed behavior of the system before we built it, we decided to use the OPNET simulation to evaluate the ALAX system before it was built. The performance of the ALAX could be predicted by analyzing the results of the OPNET simulation, and the optimal architecture of the ALAX developed by devising the proper number of transputers and the proper packet buffer size of the ALAX system.<P

ALAX- A P1355-Based Architecture for An ATM LAN Access Switch, with Application to ATM Onboard Switching

We draw attention to the new IEEE P1355 Standard for Heterogeneous InterConnect as a possible platform to support several onboard processing functions, including onboard communications and onboard ATM switching. The main features of IEEE P1355 are illustrated through a discussion of the basic principles and protocol architecture of ALAX, the ATM LAN Access Switch, currently under design in the Laboratory for Advanced Switching Technologies at the University of Maryland, College Park

A multi-level system quality improvement intervention to reduce racial disparities in hypertension care and control: study protocol

BACKGROUND: Racial disparities in blood pressure control have been well documented in the United States. Research suggests that many factors contribute to this disparity, including barriers to care at patient, clinician, healthcare system, and community levels. To date, few interventions aimed at reducing hypertension disparities have addressed factors at all of these levels. This paper describes the design of Project ReD CHiP (Reducing Disparities and Controlling Hypertension in Primary Care), a multi-level system quality improvement project. By intervening on multiple levels, this project aims to reduce disparities in blood pressure control and improve guideline concordant hypertension care. METHODS: Using a pragmatic trial design, we are implementing three complementary multi-level interventions designed to improve blood pressure measurement, provide patient care management services and offer expanded provider education resources in six primary care clinics in Baltimore, Maryland. We are staggering the introduction of the interventions and will use Statistical Process Control (SPC) charting to determine if there are changes in outcomes at each clinic after implementation of each intervention. The main hypothesis is that each intervention will have an additive effect on improvements in guideline concordant care and reductions in hypertension disparities, but the combination of all three interventions will result in the greatest impact, followed by blood pressure measurement with care management support, blood pressure measurement with provider education, and blood pressure measurement only. This study also examines how organizational functioning and cultural competence affect the success of the interventions. DISCUSSION: As a quality improvement project, Project ReD CHiP employs a novel study design that specifically targets multi-level factors known to contribute to hypertension disparities. To facilitate its implementation and improve its sustainability, we have incorporated stakeholder input and tailored components of the interventions to meet the specific needs of the involved clinics and communities. Results from this study will provide knowledge about how integrated multi-level interventions can improve hypertension care and reduce disparities. TRIAL REGISTRATION: ClinicalTrials.gov NCT0156686

ALAX P1355-Based Architecture for an ATM LAN Access Switch with Application on ATM Onboard Switching

We drew attention to the new IEEE P1355 Standard for Heterogeneous InterConnect as a possible platform to support several onboard processing functions, including onboard communications and onboard ATM switching. The main features of IEEE P1355 are illustrated through a discussion of the basic principles and protocol architecture of ALAX, the ATM LAN Access Switch, currently under design in the Laboratory for Advanced Switching Technologies at the University of Maryland, College Park

ATM LAN Access Switch (ALAX): Protocol Architecture (LAN Emulation Version)

This document describes the protocol architecture of the LAN Emulation Version of the ATM LAN Access Switch (ALAX). The main function of the ALAX is to provide an interface between legacy LAN and ATM world giving network managers the option of gradually integrating ATM technology into their existing networks. To provide this functionality to the ALAX system, we decided to implement two versions of the ALAX system. One is the LAN emulation version and the other is the Multi Protocol Over ATM version. The most important design characteristics of the ALAX is the adoption of the IEEE P1355 Standard for Heterogeneous Inter Connect (HIC)[1] as the data communication paths within the ALAX switching system. This makes it possible to design the PC- based parallel architectured high performance switching system in conformance with emerging open technologies and related standards. The protocols needed within the LAN Emulation version of the ALAX include LAN Emulation, Bridging Relay function, P1355, MAC Mapping Layer (MML), MAC, LAN Physical, AAL5, ATM and ATM Physical Layer. Some other protocols needed in the ALAX include the ATM signaling which is defined in ATM Forum UNI 3.0[2] , Network Management (SNMP or CMIP)[3], Graphic User Interface and some main control functions of the ALAX. The details of all these protocols, the relationship among these protocols and the implementations of these protocols are described in this document.<P