TECH DIGITAL RESOURCE LIBRARY

University of Southern California


Latest Content From University of Southern California

Whitepaper: An On-Line Reorganization Framework for SAN File Systems

by University of Southern CaliforniaJan 01, 2008

Storage Area Network (SAN) architectures strive to minimize the increasing cost of managing storage by consolidating storage devices. A SAN is a special-purpose network that interconnects different data storage devices with servers. While there are many definitions for SAN, there is a general consensus that it provides access at the granularity of a block and is typically used for database applications. This paper focuses on SAN switches that include embedded storage management software in support of virtualization. The researchers describe an On-line Re-organization Environment that controls the placement of data to improve the average response time of the system.


Whitepaper: Generalization of Single-Carrier and Multicarrier Cyclic Prefixed Communication

by University of Southern CaliforniaJan 01, 2008

This research paper from University of Southern California describes a cyclic prefixed communication structure that is a generalization of both the orthogonal frequency-division multiplexing (OFDM) system and the cyclic prefixed single-carrier (CP-SC) system. By exploiting the fact that a circulant matrix (CM) is also a block circulant matrix (BCM), the proposed generalized cyclic prefixed (GCP) communication system provides an additional degree of freedom that allows trade-offs among peak-to-average power ratio (PAR), bit allocation capability, and frequency diversity.


Whitepaper: Exploring How The Use Of Knowledge Management Technology Makes Communities Of Practice More Transparent

by University of Southern CaliforniaJan 01, 2008

Prior research on knowledge management and knowledge management systems has tended to assume one of two perspectives on knowledge - knowledge-as-object (e.g. knowledge is explicit) or knowledge-as-action (e.g. knowledge is tacit). However in the real world the distinction is not that straightforward. Explicit and tacit knowledge are said to be mutually constituted rather than separate and distinct. Thus in this exploratory study authors use Lave and Wenger’s (1991) concept of transparency rather than a taxonomy of knowledge types as a means to determine how technology might support knowledge work.


Whitepaper: Why Virtual Worlds Can Matter

by University of Southern CaliforniaJan 01, 2008

Virtual worlds are persistent, avatar-based social spaces that provide players or participants with the ability to engage in long-term, joint coordinated action. This paper is an effort to outline some of the things happening in and around virtual worlds which make them more than ""just games"" and which may in fact point in the direction of new forms of knowing and acting in virtual spaces and give insight into what new, technologically mediated worlds may look like in the coming decades.


Whitepaper: Structural Analysis of User Association Patterns in Wireless LAN

by University of Southern CaliforniaJan 01, 2008

It is important to characterize the fine structure of user association patterns, due to the rapid growth in Wireless Local Area Networks (WLANs). This paper focuses on understanding the structure in user’s daily Access Point (AP) association patterns in WLANs in the long run. The paper proposes new methodologies to systematically analyze the WLAN user traces and utilize USC WLAN trace as a case study.


Whitepaper: Municipal Wi-Fi Networks: The Goals, Practices, and Policy Implications of the U.S. Case

by University of Southern CaliforniaJan 01, 2008

This paper published by Wi-Fi explores the three broad questions about municipal Wi-Fi networks in the U.S. To explain municipal involvement, the paper points out that cities have both the means to provide relatively inexpensive deployment and the motives to provide wireless connectivity to city employees, foster the economic development of communities and offer universal and affordable broadband services to residents. It explores nine possible business models, ordered according to two questions, who owns the network and who operates it.


Whitepaper: Networked Infomechanical Systems: A Mobile Embedded Networked Sensor Platform

by University of Southern CaliforniaJan 01, 2008

By exploiting a constrained actuation method based on rapidly deployable infrastructure, NIMS suspends a network of wireless mobile and fixed sensor nodes in three-dimensional space. Networked InfoMechanical Systems (NIMS) introduces a new actuation capability for embedded networked sensing. This permits run-time adaptation with variable sensing location, perspective, and even sensor type.


Whitepaper: MStream: Position-Aware Mobile Music Streaming

by University of Southern CaliforniaJan 01, 2008

With the ubiquitous availability of wireless networks in many commercial and business settings, world is entering a new era of mobile computing and entertainment. Wireless networks are increasingly pervasive in many commercial and business environments. Additionally, many portable computing devices now have built-in wireless networking support. With these trends users are entering a new era of mobile computing and entertainment. This paper introduces an application named MStream for mobile handheld devices such as PDAs. MStream provides customized, location-aware streaming audio services through wireless IP networks to PDAs with GPS locators.


Whitepaper: TCP Flow Analysis for Defense Against Shrew DDoS Attacks

by University of Southern CaliforniaJan 01, 2008

This research paper explores the energy distributions of Internet traffic flows in frequency domain. Normal TCP traffic flows present some form of periodicity because of TCP protocol behavior. The results reveal that normal TCP flow is segregated from malicious flows using some energy distribution properties and discover the spectral shifting of attack flows from that of normal flows. This white paper proposes a novel defense scheme against shrew DDoS or RoQ (Reduction-of-Service) attacks.


Whitepaper: Delay Analysis and Comparison of OFDM-TDMA and OFDMA Under IEEE 802.16 QoS Framework

by University of Southern CaliforniaJan 01, 2008

This research paper discusses the delay analysis and comparison of OFDM-TDMA and OFDMA using a flow control scheme under the QoS framework of IEEE 802.16. The paper investigates the maximum packet delay performance by deriving delay bounds for several multiaccess modes with different subcarrier/time-slot assignment and bit allocation schemes. The analytical delay bounds provide insights into the performance difference among different multiaccess schemes, and demonstrate each scheme’s capability of supporting real-time, delay-sensitive multimedia applications.