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10+ ways to help your help desk (and therefore yourself)
If you're a go-to resource for your organization's help desk, you can make your job easier by making their job easier. Calvin Sun looks at some things you can do to make help desk operations go more smoothly -- which will pay off for you in return.This download is also available as an entry in our 10 Things blog.

Performance, Area and Bandwidth Implications on Large-Scale CMP Cache Design
Large-scale CMP (LCMP) platforms that consist of 10s of cores for throughput computing will soon become reality. The performance and scalability of these architectures is highly dependent on the design of the cache hierarchy. The goal of this paper is to explore the cache design space for LCMP platforms. This exploration problem is approached by developing a constraint-aware analysis methodology (CAAM). CAAM first considers two important constraints and limitations that the LCMP cache design needs to account for - area constraints and on-die / off-die bandwidth limitations. Based on the approximate area constraints, a viable range of cache hierarchy options is determined. The bandwidth requirements are then estimated for these cache hierarchy options by running server workload traces on the LCMP performance model.

Streaming Stored Continuous Media Over Fair-Share Bandwidth
This paper investigates the impact of the long-term behavior of fair-share bandwidth on transmission schemes for streaming stored Continuous Media (CM). To obtain typical fair-share bandwidth conditions, a series of Internet experiments is performed in which the paper monitors TCP bulk-data transfers between various sites, and collect average TCP throughput traces. The collected traces exhibit high-variability over a broad range of time scales as well as self-similar scaling behavior over longer time scales. Under fair-share bandwidth conditions, the paper evaluates the performance of a series of data transmission schemes for non-layered CM, and of several bandwidth allocation schemes for streaming layered CM.

Bandwidth and Latency: Their Changing Impact on Performance
Bandwidth and latency are familiar topics for IT. Both relate to system performance, but in a different fashion; both have improved significantly over the years, but at a very different pace. Their performance impact is also changing as hardware and software technology progresses. This paper may have to update design strategies in hardware, software, and protocols to cope. The paper examines their impact on response time from a performance analysis perspective and sheds some new light on how to manage the bandwidth imbalance at different devices and the imbalance between bandwidth and latency.

Resource Planning and Bandwidth Allocation in Hybrid Fiber-Coax Residential Networks
The introduction of new high bandwidth services such as video-on-demand by cable operators will put a strain on existing resources. It is important for cable operators to know how many resources to commit to the network to satisfy customer demands. This paper develops models of voice and video traffic to determine the effect on demand growth on hybrid fiber-coax networks. The paper obtains a set of guidelines that network operators can use to build out their networks in response to increased demand. The paper begins with one type of traffic and generalize to an arbitrary number of high-bandwidth CBR-like services to obtain service blocking probabilities. These computations help to determine how cable networks would function under various conditions (i.e., low, medium, and heavy loads).

Bandwidth Profiles for Ethernet Services
This paper provides a comprehensive technical overview of bandwidth profiles for Ethernet services, based on the work of the Metro Ethernet Forum (MEF) Technical Committee. The paper is intended to help buyers, users, providers of Ethernet services, and equipment and semiconductor vendors understand the various types, characteristics and usage of bandwidth profiles as defined by the MEF. This paper will be updated as new work emerges from the MEF Technical Committee.

A QoS-Based Bandwidth Management Scheme in Heterogeneous Wireless Networks
Providing a high bandwidth connection for end users anywhere and at anytime is the ultimate goal for the wireless community. Integrating different access technologies is a major step towards such a goal. In a companion paper, a generic reservation-based QoS framework has been proposed and discussed for integrated cellular and WLAN networks. The bandwidth adaptation algorithm, as the key factor of the proposed framework, decides how to adjust the QoS to maintain ongoing sessions at a satisfactory level with efficient use of the system resources. This paper proposes a novel QoS management scheme based on per class degradation. Its performance has been compared with the previous proposed adaptation algorithm.

Bandwidth Consumption Control and Service Differentiation for Video Streaming
Multimedia streaming is resource demanding. It may starve other applications such as file transfer sharing the network, for example, in a smart home. To address the problem, a fuzzy logic control to bound the bandwidth consumption of multimedia streams is applied. This paper also differentiates the video quality for streams with different levels of importance. The transmission rate control and service differentiation schemes are implemented and evaluated in the department network where a number of different applications may coexist at the same time. Performance evaluation results show that the video streaming system can support the specified bit rate bound and differentiate the service to efficiently utilize the limited bandwidth.

ICA Client Bandwidth Analysis Test Environment
This paper describes the testing environment used to perform bandwidth testing for the ICA Client Bandwidth Analysis white paper. The purpose of this paper is to describe the bandwidth impact of common ICA Client settings in a MetaFrame environment. The ICA Client bandwidth test environment consisted of a MetaFrame server, a server used for network captures, and a client workstation, all on a single isolated network connected by a hub. A hub was used in this testing environment in order to watch all ICA traffic between the client workstation and the MetaFrame server from a separate network capture server (a switch may be used if it has port mirroring capabilities).

An Efficient Host-to-Host Available Bandwidth Estimation Scheme
This paper takes an initiative from TOPP and SLoPS and its essence is to reduce the number of probing and error inherent in estimating the available bandwidth along a network path. This paper aims at proposing an algorithm for estimating available bandwidth with shorter measurement latency. The method that is iterative generates new probing rates by proportionally decreasing an initial probing rate as a function of backlogged delays as a result of extra traffics along the path. The proposed algorithm, when implemented in ns2 under same simulation setup in TOPP; produced the available bandwidth estimate at about 30% of the number of iterations required for TOPP with a relative estimation error of 5% against 9% in TOPP.

Analysis of Bandwidth Reservation Algorithms in HIPERLAN/2
This paper focuses on performance of channel access methods in the HIPERLAN/2 standard. It discusses commonly used approaches to bandwidth allocation and presents a modified algorithm for effective bandwidth management based on pre-scheduled resource grants. Wireless LANs have gained market acceptance over the last several years, partly because of the increased demand for wireless communications and advances in portable computers and networking technology. Although the first WLAN solutions were used as a cordless replacement for Ethernet networks, it is clear that in the near future WLANs will have to keep up with the growing demand for bandwidth-consuming multimedia traffic.

Minimizing Bandwidth Requirements for On-Demand Data Delivery
Two recent techniques for multicast or broadcast delivery of streaming media can provide immediate service to each client request, yet achieve considerable client stream sharing which leads to significant server and network bandwidth savings. This paper considers how well these recently proposed techniques perform relative to each other, and whether there are new practical delivery techniques that can achieve better bandwidth savings than the previous techniques over a wide range of client request rates.

Measurement of the Bandwidth of Helicon Maser
Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid - state plasmas of metals and semiconductors when a strong magnetic field is applied. In Helicon Maser (HM) the helicons are exited by RFs much higher than the helicon generation frequency. The higher frequency e/m field may be called a pumping field. In analogy with the usual maser (or laser) the magnetized semiconductor sample plays the role of active material and the connecting cable - the role of high quality external resonator. The bandwidth of HM is much narrower than in case of isolated sample (the same situation as in case of laser). The new method of HM bandwidth measurement is considered. InSb and Ge were used for active materials.

Bandwidth Reduction for Video Processing in Consumer Systems
The architecture of present video processing units in consumer systems is usually based on various forms of processor hardware, communicating with an o -chip SDRAM memory. Examples of these systems are currently available MPEG encoders and decoders, and high-end television systems. Due to the fast increase of required computational power of consumer systems, the data communication to and from the o -chip memory has become the bottleneck in the overall system performance (memory wall problem). This paper presents a strategy for mapping pixels into the memory for video applications such as MPEG processing, thereby minimizing the transfer overhead between memory and the processing.

Improving XCP to Achieve Max-Min Fair Bandwidth Allocation
TCP is shown to be inefficient and instable in high speed and long latency networks. The eXplicit Control Protocol (XCP) is a new and promising protocol that outperforms TCP in terms of efficiency, stability, queue size, and convergence speed. However, Low et al. recently discovered a weakness of XCP. In a multi-bottleneck environment, XCP may achieve as low as 80% utilization at a bottleneck link and consequently some flows may only receive a small fraction of their max-min fair rates. This paper proposes iXCP, an improved version of XCP. Extensive simulations show that iXCP overcomes the weakness of XCP, and achieves efficient and fair bandwidth utilization in both single- and multi-bottleneck environments.