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The United States increasingly relies on cyber-physical systems to conduct military and commercial operations. Attacks on these systems have increased dramatically around the globe. The attackers constantly change their methods, making state-of-the-art commercial and military intrusion detection systems ineffective. In this paper, we present a model to identify functional behavior of network devices from netflow traces. Our model includes two innovations. First, we define novel features for a host IP using detection of application graph patterns in IP’s host graph constructed from 5-min aggregated packet flows. Second, we present the first application, to the best of our knowledge, of Graph Semi-Supervised Learning (GSSL) to the space of IP behavior classification. Using a cyber-attack dataset collected from NetFlow packet traces, we show that GSSL trained with only 20% of the data achieves higher attack detection rates than Support Vector Machines (SVM) and Naive Bayes (NB) classifiers trained with 80% of data points. We also show how to improve detection quality by filtering out web browsing data, and conclude with discussion of future research directions.

With the ever-increasing amount of data being stored via social media, mobile telephony base stations, and network devices etc. the database systems face severe bandwidth bottlenecks when moving vast amounts of data from storage to the processing nodes. At the same time, Storage Class Memory (SCM) technologies such as Phase Change Memory (PCM) with unique features like fast read access, high density, non-volatility, byte-addressability, positive response to increasing temperature, superior scalability, and zero standby leakage have changed the landscape of modern computing and storage systems. In such a scenario, we present a storage system called FLEET which can off-load partial or whole SQL queries to the storage engine from CPU. FLEET uses an FPGA rather than conventional CPUs to implement the off-load engine due to its highly parallel nature. We have implemented an initial prototype of FLEET with PCM-based storage. The results demonstrate that significant performance and CPU utilization gains can be achieved by pushing selected query processing components inside in PCM-based storage.

Damage to infrastructure is a real concern at present, caused primarily by worldwide climate anomalies, global warming, and natural disasters. Korea has begun research to develop a high precision patch/implant system using new IT techniques since 2011 and technologies which must be developed for this research are those which measure and evaluate the soundness and safety of structures based on the measurements of an attached sensor. During the research period since 2011, optical fiber sensor patches and wireless sensor capsule implants along with various sensor technologies, stress sensing and structural condition evaluation algorithm have been developed effectively for network hardware technologies as prototype version. Similarly high precision image processing for automatic crack extraction have been developed along with radiation sensor application technologies, combined management/control technologies for developed systems, and practical technologies for building and large scale structure. Through the results, it is expected that we acquire higher sensor system performance with a measurement scope (for precision, etc.) goal at least 200% better than conventional sensor systems.

Triggered by the recent vast demands of the information bandwidth, high speed transmission networking system, such as 100G/400G, have been developed and installed with extremely high speed. In order to lead the proper concept/design of the leading edge optical components which is applied for these high speed networking equipment, de-fact standardization bodies such as IEEE802.3/OIF have made important roles in the industry. The demands of the bandwidth will still continue to increase with endless degree, and therefore the future migration towards higher speed transceivers such as 1T class, and also towards the smaller form factor transceivers is absolutely inevitable, and to be examined.

With the improvement of people’s living standard, the requirement of network is higher and higher. The rate and capacity of network communication are rising all the time, it ’s outstanding on the backbone networks. The rate of backbone network had improved from 10G to 100G in recent years. This change also put forward new requirement for optical network equipment . The key technologies of lower order cross-connect equipment is discussing in this passage. This passage mainly discusses the following aspects: time division multiplexing of STM-1 lower-order pointer interpretation and lower -order pointer generation. By using the technologies discussed in this passage, the lower -order cross-connect devices has the higher cross-connect capacity under consuming the same logic resource, and the equipment will meet the requirement of the backbone network transmission capacity.

This article discusses features of the parallel hashing for the designing of the frame filtering tables in distributed computing systems. The proposed method of filtering tables design can reduce the time of frame processing by network bridges and switches and provide a low probability of filtering table overflowing. The optimal number of parallel tables was determined for a given amount of memory for table design.

Mobile, high throughput mid-range data communications and robust real-time data networking in the subsea environment that can accommodate high bandwidth sensors such as optical imagers have a potentially high impact as enabling technologies for a variety of future subsea operations in the areas of distributed sensing and real-time wireless feedback and control of unmanned undersea vehicles. Although much work has been done recently in the field of undersea optical free space communications and networking, to date there has yet to be an implementation of a complete multi-node undersea wireless optical data communications network. The deployment and testing of optical wireless network equipment in the undersea environment is expensive and time-consuming, and there is a clear need for a network simulation framework that will allow researchers to evaluate the performances of different networking concepts/configurations under realistic operational and environmental constraints. This paper describes a network simulation approach that uses an accurate time dependent Monte Carlo channel model to simulate the networking physical layer, which can be used in conjunction with higher network layer protocols to simulate larger scale network performance and to help determine hardware requirements for overall network system design in a variety of undersea channel conditions.

Based on current trends for both military and commercial applications, the use of mobile devices (e.g. smartphones and tablets) is greatly increasing. Several military applications consist of secure peer to peer file sharing without a centralized authority. For these military applications, if one or more of these mobile devices are lost or compromised, sensitive files can be compromised by adversaries, since COTS devices and operating systems are used. Complete system files cannot be stored on a device, since after compromising a device, an adversary can attack the data at rest, and eventually obtain the original file. Also after a device is compromised, the existing peer to peer system devices must still be able to access all system files. McQ has teamed with the Cryptographic Engineering Research Group at George Mason University to develop a custom distributed file sharing system to provide a complete solution to the data at rest problem for resource constrained embedded systems and mobile devices. This innovative approach scales very well to a large number of network devices, without a single point of failure. We have implemented the approach on representative mobile devices as well as developed an extensive system simulator to benchmark expected system performance based on detailed modeling of the network/radio characteristics, CONOPS, and secure distributed file system functionality. The simulator is highly customizable for the purpose of determining expected system performance for other network topologies and CONOPS.

Data volume is getting larger every day in Mask Data Preparation (MDP). In the meantime, faster data handling is always required. MDP flow typically introduces Distributed Processing (DP) system to realize the demand because using hundreds of CPU is a reasonable solution. However, even if the number of CPU were increased, the throughput might be saturated because hard disk I/O and network speeds could be bottlenecks. So, MDP needs to invest a lot of money to not only hundreds of CPU but also storage and a network device which make the throughput faster. NCS would like to introduce new distributed processing system which is called "NDE". NDE could be a distributed disk system which makes the throughput faster without investing a lot of money because it is designed to use multiple conventional hard drives appropriately over network. NCS studies I/O performance with OASIS® data format on NDE which contributes to realize the high throughput in this paper.

The increasing demand for higher bit rates in access networks requires fiber deployment closer to the subscriber resulting in fiber-to-the-home (FTTH) access networks. Besides higher access bit rates optical access network infrastructure and related technologies enable the network operator to establish larger service areas resulting in a simplified network structure with a lower number of network nodes. By changing the network structure network operators want to benefit from a changed network cost structure by decreasing in short and mid term the upfront investments for network equipment due to concentration effects as well as by reducing the energy costs due to a higher energy efficiency of large network sites housing a high amount of network equipment. In long term also savings in operational expenditures (OpEx) due to the closing of central office (CO) sites are expected. In this paper different architectures for optical access networks basing on state-of-the-art technology are analyzed with respect to network installation costs and power consumption in the context of access node consolidation. Network planning and dimensioning results are calculated for a realistic network scenario of Germany. All node consolidation scenarios are compared against a gigabit capable passive optical network (GPON) based FTTH access network operated from the conventional CO sites. The results show that a moderate reduction of the number of access nodes may be beneficial since in that case the capital expenditures (CapEx) do not rise extraordinarily and savings in OpEx related to the access nodes are expected. The total power consumption does not change significantly with decreasing number of access nodes but clustering effects enable a more energyefficient network operation and optimized power purchase order quantities leading to benefits in energy costs.

A reconfigurable protection is extended in ASON survivability testbed SURBED, the performance and extra overhead are presented and also compared with several survivability techniques (1+1, shared mesh, rerouting, etc) in SURBED. Pre configured protection cycles (p-cycle) is a kind of preconfigured protection mechanism that can have mesh-like resource efficiency and ring-link protection speed. But under multi-region survivable network, the topology and resource information is not always available due to policy reasons or other else, so distributed approach with agent negotiation is attractable. As the dimensions of WDM optical network grows larger and larger, it tends to be a mesh structure. Based on SURBED, we take extensive simulation to investigate the performance of different signaling strategies by multi-region agent negotiations. Unlike previous work, we focus on the reconfiguring process rather than the switching over operation of control plane in ASON. The backbone is overlaid, in which most of devices are IP router networks. Routers are interconnected by fibers or SDH or WDM links. It is the same with non-reconfigured p-cycle, the reconfiguration need a criterion, and here we use the network real-time performance as a reconfiguration trigger to take actions on p-cycle reconfiguration.

Requirement of packet transport network based on MPLS-TP are analyzed including in transport plane, OAM, survivability, QoS, control plane and management plane. MPLS-TP standard status is also introduced.

This invited talk will review the development of ultrafast all-optical LAN technologies, conducted by New Energy and Industrial Technology Development Organization (NEDO), Japan. First, we will provide an outlook for the energy issues of future network equipment, then point out the importance of optical circuit-switched networks, particularly for the future local area networks in the forthcoming ultra-high definition, or 'Super Hi-vision', video era. To realize ultrafast all-optical LAN, we argue that scalable network interface card technologies are the key. As specific development topics, 40G-CMOS based optical transceivers, picosecond all-optical switching using the inter-subband transition (ISBT) devices, high-operating-temperature semiconductor optical amplifiers (SOA), and integrated wide-dynamic-range wavelength converters will be introduced.

It is the research hotspot of current broadband network to combine voice service, data service and broadband audio-video service by IP protocol to transport various real time and mutual services to terminal users (home). Home Networking is a new kind of network and application technology which can provide various services. Home networking is called as Digital Home Network. It means that PC, home entertainment equipment, home appliances, Home wirings, security, illumination system were communicated with each other by some composing network technology, constitute a networking internal home, and connect with WAN by home gateway. It is a new network technology and application technology, and can provide many kinds of services inside home or between homes. Currently, home networking can be divided into three kinds: Information equipment, Home appliances, Communication equipment. Equipment inside home networking can exchange information with outer networking by home gateway, this information communication is bidirectional, user can get information and service which provided by public networking by using home networking internal equipment through home gateway connecting public network, meantime, also can get information and resource to control the internal equipment which provided by home networking internal equipment. Based on the general network model of home networking, there are four functional entities inside home networking: HA, HB, HC, and HD. (1) HA (Home Access) - home networking connects function entity; (2) HB (Home Bridge) Home networking bridge connects function entity; (3) HC (Home Client) - Home networking client function entity; (4) HD (Home Device) - decoder function entity. There are many physical ways to implement four function entities. Based on theses four functional entities, there are reference model of physical layer, reference model of link layer, reference model of IP layer and application reference model of high layer. In the future home network should have broadband network function, public network function, and compositive multi-service and multi-application function, etc.

With the rapid increase of Ethernet speed, it is of necessity to improve transport performance of Ethernet physical channel. Based on frame structure defined in IEEE Std 802.3, a kind of frame structure comprising forward error correction (FEC) contents is presented. A FEC method based on the frame structure is brought forward. The method includes error correction functions as well as a mechanism to detect the performance of the physical channel and adjust the FEC configuration adaptively in or der to decrease the cost br ought by the FEC me thod. An Ethernet interface using the FEC method can interwork with an ordinary non FEC Ethe rnet interface. Detailed analysis for performance of the FEC method is given too. A kind of network device that realizes the FEC functions is designed and a test topology is set up to test and evaluate the FEC method. Keywords: Forward Error Correction, Optical Ethern et, MAC, Frame Structure, Adaptive 1. INTRODUCTION Ethernet is one of the widely applied network technologies, However, comparing the current Ethernet physics channel with the traditional physics channel, hug e change has ta ken place: (1)Under ma ny circumstances, long fiber is taken as Ethernet transport media. (2) Ethernet transport distance has extented from a hundred metres to several kilometers, even to tens of kilometres and farther. (3)Ethernet port speed has extented from 10 Mbps to 100 Mbps, 1000 Mbps, 10 Gbps even to 100 Gbps and higher. This requires optical channel transmitting Ethernet signal should have excellent performance. However, current optical channels are various and many of them can’t meet future application request. Various noise source, inter-code interf erence caused by dispersivity and errors brought about by timing jitter can result in errors of the physics channel. Optical transmission Technologies such as SDH (Synchronous Digital Hierarchy) and WDM (Wave-Division Multiplexing) etc. have adopted appropriate mechanism to correct channel errors[1][2], and there are some related researches [3][4]. Likewise, high-speed optical Ethernet is transmit ted on optical channel and it is also necessary to solve the problem of physics channel errors. According to mathematics analysis, probability of correctly tr ansporting Ethernet data packets whose lengths are greater than 1280 bytes will be near to 0 when bit error rate of the physics channel is greater than 5*10

This paper introduces the new Japanese academic backbone network called SINET3, which has been in full-scale operation since June 2007. SINET3 provides a wide variety of network services, such as multi-layer transfer, enriched VPN, enhanced QoS, and layer-1 bandwidth on demand (BoD) services to create an innovative and prolific science infrastructure for more than 700 universities and research institutions. The network applies an advanced hybrid network architecture composed of 75 layer-1 switches and 12 high-performance IP routers to accommodate such diversified services in a single network platform, and provides sufficient bandwidth using Japan's first STM256 (40 Gbps) lines. The network adopts lots of the latest networking technologies, such as next-generation SDH (VCAT/GFP/LCAS), GMPLS, advanced MPLS, and logical-router technologies, for high network convergence, flexible resource assignment, and high service availability. This paper covers the network services, network design, and networking technologies of SINET3.

Our focus is on the potential of enhancing light-matter interactions by using microstructures. It has been proven that microstructures of composite materials (MCMs) are versatile means for passive optical functional integration. Here we elaborate on some motivations and preliminary results. By using MCMs, we present a few examples of enhanced functional integration for optical networks and structures for light trapping at UV-VIS (e.g., solar cells). Simulations of wavelength division multiplexing (WDM) and polarization dependent devices for network terminals at 1310 nm and 1500nm are presented. A simple principle was used to demonstrate total absorption of visible spectrum around 400-500 nm, which may benefit application such as solar cells.

ASON is new type of optical network which can offer the flexibility for bandwidth allocation and fast provision of the new service. However, until now there still are many non-ASON optical networks. It is a challenging issue to reconstruct them into ASON smoothly. In this paper, we propose a new reconstructing technology. This technology performs the function of the control plane such as link management, path management and interface management by an embedded top-set-box (ETSB). The ETSB is located between EMS and the traditional NE such as DWDM, WDM, SDH, etc. By this technology the hardware module of the existing optical network element (NE) need not modification. Thus, compared with other reconstructing technologies, the cost and the risk of this reconstructing technology are smaller.

There has been a lack of investigations related to low yield explosives instigated by terrorist on small but high occupancy buildings. Also, mitigating the threat of terrorist attacks against high occupancy buildings with network equipment essential to the mission of an organization is a challenging task. At the same time, it is difficult to predict how, why, and when terrorists may attack theses assets. Many factors must be considered in creating a safe building environment. Although it is possible that the dominant threat mode may change in the future, bombings have historically been a favorite tactic of terrorists. Ingredients for homemade bombs are easily obtained on the open market, as are the techniques for making bombs. Bombings are easy and quick to execute. This paper discusses the problems with and provides insights of experience gained in analyzing small scale explosions on older military base buildings. In this study, we examine the placement of various bombs on buildings using the shock wave simulation code CTH and examine the damage effects on the interior of the building, particularly the damage that is incurred on a computer center. These simulation experiments provide data on the effectiveness of a building's security and an understanding of the phenomenology of shocks as they propagate through rooms and corridors. It's purpose is to motivate researchers to take the seriousness of small yield explosives on moderately sized buildings. Visualizations from this analysis are used to understand the complex flow of the air blasts around corridors and hallways. Finally, we make suggestions for improving the mitigation of such terrorist attacks. The intent of this study is not to provide breakthrough technology, but to provide a tool and a means for analyzing the material hardness of a building and to eventually provide the incentive for more security. The information mentioned in this paper is public domain information and easily available via the internet as well as in any public library or bookstore. Therefore, the information discussed in this paper is unclassified and in no way reveals any new methodology or new technology.

Ring-based network overlays have attractive characteristics for group communications such as inherent reliability and single fault-tolerance. However, ring networks also generally have longer paths and thus higher delay and delay jitter. In order to provide scalability as the number of group members grows, large single rings may be broken into smaller multi-rings interconnected together at the same level or interconnected in a multi-level hierarchy of rings. In this paper we consider different approaches to providing scalable battlespace group communications using multi-ring techniques -- classifying the techniques according to the primary military requirements of security and survivability. For multi-rings at the same level, an optimal number of rings to cover the group members may be approximated and these rings may then be interconnected at end systems or bridged via network devices. For hierarchical rings the number of levels and the number of rings per level may both be approximated. These results are dependent on application QoS demands and the underlying network infrastructure in terms of topology (dense versus sparse) and link bandwidths (bottleneck capacities). Network-centric warfare is not simply a combination of communication, intelligence, and signals, but rather warfare that leverages off a common network to support different purposes. While group communications based on a single virtual ring overlay may satisfy the most important requirements for survivability and security, scalability may force redesign. Thus comparing the characteristics of different multi-ring techniques provides an insight into which battlespace applications may be supported via virtual rings.

Ubiquitous communications will be the next era in the evolving communications revolution. From the human perspective, access to information will be instantaneous and provide a revolution in services available to both the consumer and the warfighter. Services will be from the mundane - anytime, anywhere access to any movie ever made - to the vital - reliable and immediate access to the analyzed real-time video from the multi-spectral sensors scanning for snipers in the next block. In the former example, the services rely on a fixed infrastructure of networking devices housed in controlled environments and coupled to fixed terrestrial fiber backbones - in the latter, the services are derived from an agile and highly mobile ad-hoc backbone established in a matter of minutes by size, weight, and power-constrained platforms. This network must mitigate significant changes in the transmission media caused by millisecond-scale atmospheric temperature variations, the deployment of smoke, or the drifting of a cloud. It must mitigate against structural obscurations, jet wash, or incapacitation of a node. To maintain vital connectivity, the mobile backbone must be predictive and self-healing on both near-real-time and real-time time scales. The nodes of this network must be reconfigurable to mitigate intentional and environmental jammers, block attackers, and alleviate interoperability concerns caused by changing standards. The nodes must support multi-access of disparate waveform and protocols.

Currently existing dense wavelength division multiplexing (DWDM) networks start to migrate from numerous point-to-point links towards meshed, transparent, optical networks with dynamically routed light paths. This increases the need for appropriate network monitoring and supervision methods. Optical performance monitoring (OPM) has to be cost-effective. Thus additional spendings for OPM have to be significantly smaller than the savings in OPEX due to increased reliability and ease of operation, administration, and maintenance (OAM). We elaborate on different advanced monitoring concepts. First, we discuss general failure scenarios in meshed networks. Then we describe software based failure root cause analysis and its implementation. We conclude that by implementing appropriate software algorithms in the network hardware effort can be significantly reduced. Finally, we assess different advanced OPM methods which may show up as useful to enable OPM in future optical networks.

A multilayer network is a complex system composed of many devices which in turn are composed of many subsystems. A failure event changes the configuration of the multilayer network, triggering recovery at more than one layer. Proving that a circuit will work after provisioning operations is an important step to preventing misconfiguration of network devices. We have been working on implementing the consistency checker for one layer. It creates a network representation and adds changes to the network. To verify operation of the system, graphical representation of packets are exchanged between different ports. To understand such a systems, we describe them with a block diagram representing important resources.

With the development of mobile telecommunication network, users of CDMA advanced their request of network service quality. While the operators also change their network management object from signal coverage to performance improvement. In that case, reasonably layout & optimization of mobile telecommunication network, reasonably configuration of network resource, improvement of the service quality, and increase the enterprise's core competition ability, all those have been concerned by the operator companies. This paper firstly looked into the flow of CDMA network optimization. Then it dissertated to some keystones in the CDMA network optimization, like PN code assignment, calculation of soft handover, etc. As GSM is also the similar cellular mobile telecommunication system like CDMA, so this paper also made a contrast research of CDMA and GSM network optimization in details, including the similarity and the different. In conclusion, network optimization is a long time job; it will run through the whole process of network construct. By the adjustment of network hardware (like BTS equipments, RF systems, etc.) and network software (like parameter optimized, configuration optimized, capacity optimized, etc.), network optimization work can improve the performance and service quality of the network.

As many kinds of media converge to the Internet, the backbone will face new demands not only in terms of bandwidth, but also in terms of services. Therefore it is certain that Internet will evolve into IP-over-WDM based all-optical network. Obviously, the optical router will be a crucial network device. In the paper, we propose a practical architecture of optical router. Based on all-optical labeled burst switching, this architecture supports all-optical edge-to-edge data routing and transport services with transparent data rate and format, and simplifying protocol and operations. From the viewpoint of practicality, some key issues during the design have been studied and analyzed, and corresponding feasible solutions to them are put forward respectively. Finally an experimental system and results are shown.

This paper presents an architecture that provides a unified web interface to managed network devices that support CORBA, OSI or Internet-based network management protocols. A client gains access to managed devices through a web browser, which is used to issue management operations and receive event notifications. The proposed architecture is compatible with both the OSI Management reference Model and CORBA. The steps required for designing the building blocks of such architecture are identified.

Optical Label Switching (OLS) is one of the practical manners of optical packet switching. It is a main research domain in optical networks. The advantage of OLS is its bandwidth efficiency and ability to support various network devices. There are a lot of practical problems need to be resolved. Today, research into OLS technology has focused on key networking and hardware issues such as high-speed optical switch, optical storage component, and network nodes source distribution optimization algorithm. The optical Label Header contains header synchronizing bits, routing address bits, etc. Header reading and rewriting includes synchronizing, routing and checking technologies. So it is the key issue in the OLS, and has very important research and application values. In this paper, a novel proposed fabric scheme was discussed to achieve the function of the header reading and rewriting. It can be applied to the high-speed header reading and rewriting to satisfy the requirements of practical applications. The fabric scheme adopts a high-speed tunable laser and wavelength converter to rewrite the header. The high-speed tunable laser is based on Grated Coupler Sampled Reflector (GCSR) structure and the wavelength converter is based on Cross-Phase Modulation (XPM) in a Semiconductor Optical Amplifier (SOA) and a Mach-Zehnder Interferometer (MZI) structure. The synchronization of the packet in the node also be discussed.

As part of its technology development program for the Army's Future Combat System (FCS), the Defense Advanced Research Projects Agency (DARPA) has been working to develop the enabling communications technology needed to revolutionize the Army's future land force into a network centric force capable of operation at a level of synchronization, mobility, and force effectiveness which has been heretofore unachievable. Key to this network centric operation will be a scalable suite of multiband wireless, mobile adhoc networking devices which operate with directional antennas to provide significant improvements in capacity, Anti-jam, and Low Probability of Detection (LPD). This paper reviews the underlying motivation for this technology development and summarizes the numerous technology investments being made by DARPA under their FCS Communications technology program.

Network researchers employ a variety of experimental methods and tools including analytic modeling techniques, simulators, and widely deployed measurement infrastructures. It is natural to assume that the overall scope of network research may be limited by the type and capability of the tools and test systems that are available. In this paper we describe a new, bench--style approach for conducting network research that we argue is essential for effectively investigating different classes of important problems. We describe the architecture for the workbench environment which enables this approach - what we call the Internet Instance Laboratory (IIL). The conceptual model for an IIL is a highly configurable laboratory environment containing commercial networking equipment typical of any end--to--end path in the Internet. An IIL would also have the capability to create accurately a broad range of conditions across all networking layers. The two most important advantages of an IIL are the ability to instrument entire end--to--end paths and the ability to install new equipment or protocols in any location in the environment. Clearly, neither of these opportunities is available in the live Internet. While an IIL offers significant capabilities, developing such a testbed is not without significant challenges. We describe these challenges and approaches for addressing them. Finally, we discuss different classes of research questions which would become tractable if an IIL were available.

Technological communities that are formed on the basis university, industry and government partnerships are developing and deploying advanced network applications and technologies, accelerating the creation of tomorrow's Internet. Alcatel and North Carolina State University (NCSU) have jointly launched a virtual Lab between Alcatel's Research & Innovation Center in Plano, TX and NCSU campus at Raleigh, NC across the Internet2 national backbone network. The objective of this co-operative work is to conduct a large-scale field trial in the currently deployed state of the art QoS technologies and investigate areas of improvement. Results from phase one of our work in a Differentiated services (DiffServ) experiments over this testbed involving network equipment from Alcatel and other third party vendors show that DiffServ is capable of delivering the premium service using its expedited forwarding (EF) per-hop behaviour (PHB) for a large class of bandwidth starving applications. However, it is found that DiffServ needs some additional mechanisms to efficiently deliver similar services for jitters and delay sensitive applications, especially in a condition of severely congested network. The situation is even more complicated when one considers resource-sharing environments beyond the extreme cases of EF and best effort (BE) only. The second phase of our work involves investigating empirically and through simulation, a fine-grained new integrated scheduling scheme to extend the DiffServ with a variety of adaptive queue management (AQM) solutions and study their effect on end-to-end (e2e) DiffServ experiments involving not only EF/BE but also assured forwarding (AF) traffic.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

With the fast growth of data in multispectral image processing, the traditional storage architecture was challenged. It is currently being replaced by Storage Area Networks (SAN), which makes storage devices externalized from servers. A SAN is a separate network for storage, isolated from the messaging network and optimized for the movement of data between servers and storage devices. Nowadays, most of current SAN use Fibre Channel to move data between servers and storage devices (FC-SAN), but because of the drawbacks of the FC-SAN: for interoperability, lack of skilled professional and management tools, high implementation cost and so on, the development and application of FC-SAN was obstructed. In this paper, we introduce an IP-based Storage Area Networks architecture, which has the good qualities of FC- SAN but overcomes the shortcoming of it. The principle is: use IP technology to move data between servers and storage devices, build a SAN with the IP-based network devices (not the FC-based network device), and through the switch, SAN is attached to the LAN(Local Area Network) through multiple access. Especially, these storage devices are acted as commercial NAS devices and PC.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

One of the goals of the National Cancer Institute (NCI) cancer control program to reach more than 80% of the eligible women in mammography screening by the year 2000 was not fully realized and yet remains as a challenge. In fact, breast cancer is the only type of cancer with a positive growth rate over the last few years (+1 .2%). That is primarily due to 1)the fact that examination process is a complex and lengthy one and 2) it is not available to the majority of women who live in remote and urban sites. This problem can be solved using advanced networking technologies and signal processing algorithms. On one hand, software modules can help detect, with high precision, true negatives (TN), while marking true positives (TP) for further investigation. Since TNs are the majority of examinations on a randomly selected population, this first step reduces the load on radiologists by a tremendous amount. On the other hand, high-speed networking equipment can accelerate the required clinic-lab connection and make detection, segmentation and image enhancement algorithms readily available to the radiologists. This research describes the Asynchronous Transfer Mode (ATM) Telemammography Network (ATMTN) architecture for real-time, on-line screening, detection and diagnosis of breast cancer. ATMTN is a high-speed network integrated with associated automatic robust Computer Assisted Diagnostic (CAD) methods for mass detection

The reduction of wavelength in optical lithography, phase shift technology and optical proximity correction (OPC), requires a rapid increase in cost effective qualification of photomasks. The knowledge about CD variation, loss of pattern fidelity especially for OPC pattern and mask defects concerning the impact on wafer level is becoming a key issue for mask quality assessment. As part of the European Community supported ESPRIT projection 'Q-CAP', a new cluster concept has been developed, which allows the combination of hardware tools as well as software tools via network communication. It is designed to be open for any tool manufacturer and mask hose. The bi-directional network access allows the exchange of all relevant mask data including grayscale images, measurement results, lithography parameters, defect coordinates, layout data, process data etc. and its storage to a SQL database. The system uses SEMI format descriptions as well as standard network hardware and software components for the client server communication. Each tool is used mainly to perform its specific application without using expensive time to perform optional analysis, but the availability of the database allows each component to share the full data ste gathered by all components. Therefore, the cluster can be considered as one single virtual tool. The paper shows the advantage of the cluster approach, the benefits of the tools linked together already, and a vision of a mask house in the near future.

A high bandwidth, low latency processor interconnect has been constructed using off-the-shelf FPGAs and a small amount ofadditional logic. The Achilles system comprises a router in which the main circuit elements (the FPGAs) have been placedon ten small PCBs and connected together to make a router 'stack' and a PCI interface. On the first prototype, channelbandwidth has been measured at 28Mbytes/second and latency was measured to be 800ns. The newer low-voltage FPGAswill be used in the next Achilles variant, allowing the bandwidth capability will increase to close to the theoretical maximumfor PCI bus. The router stack and PCI interface also has application as a general purpose reconfigurable processor which may be arbitrarily extended by adding further stacks to the system.Keywords: Processor interconnect, circuit switching, reconfigurable computing 1. INTRODUCTION Commodity workstations provide low-cost computing power. However, attempting to multiply this power by connectingseveral low-cost machines together as a parallel processor is generally frustrated by lack of sufficient interconnectionbandwidth. Although some applications place sufficiently low demands on the interconnect that usable speedups may beobserved, in general the processor in even the simplest desktop machine has an appetite for data that cannot be satisfied byequivalently low-priced commodity networking hardware. To meet the demands of parallel processing, an interconnect mustnot only provide high raw communication bandwidth to enable large blocks of data to be transferred efficiently betweenprocessors, it must also provide low latency so that processors do not idle while waiting for data or synchronisation events.The most common interconnect is fast ethernet, but at 100Mbps, not only does its peak communication bandwidth fall wellbelow that of the internal processor bus (-400Mbytes/second for PCI) but it is a shared communications medium: thus itseffective bandwidth is reduced not only by message overheads but by collisions. ATM is becoming common and provideshigher raw bandwidth, but the small message size leads to relatively high overheads, packet buffering can lead to long latency(—O.5ms) and some shared resources also lead to delays induced by contention. Some proprietary systems have beendeveloped with parallel processing in mind and provide better performance, eg Myrinet demonstrates a bandwidth of

The Wake Forest University School ofMedicine and the Wake Forest UniversitylBaptist Medical Center(WFUBMC) areimplementing a second generation PACS. The first generation PACS provided helpful information about the functional andtemporal requirements of the system. It highlighted the importance of image retrieval speed, system availability, RIS/HISintegration, the ability to rapidly view images on any PACS workstation, network bandwidth, equipment redundancy, and theability for the system to evolve using standards-based components.This paper deals with the network design and implementation of the PACS. The physical layout of the hospital areasserved by the PACS, the choice of network equipment and installation issues encountered are addressed. Efforts to optimizefault tolerance are discussed.The PACS network is a gigabit, mixed-media network based on LAN emulation over ATM (LANE) with a rapidmigration from LANE to Multiple Protocols Over ATM (MPOA) planned. Two fault-tolerant backbone ATM switches serve

Currently all networking hardware must have predefined tradeoffs between latency and bandwidth. In some applications one feature is more important than the other. We present a system where the tradeoff can be made on a case by case basis. To show this we implement an extremely low latency semaphore passing network within a point to point system.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Clinical prototypes of digital tele-ultrasound systems at the Bowman Gray School of Medicine have provided insight into various design architectures. Until network equipment costs decrease, hybrid systems often provide good cost/feature mixes by using high-cost networking equipment only when digital networking is required. Within the hospital using remote ultrasound system, a video and audio router interconnects the video output of ultrasound modalities and technologist communications subsystems. This is done either manually or by remote signaling, depending on the size of the ultrasound infrastructure and the cost of a remote signaling subsystem. For extramural sites and in hospital areas too distant for cost- effective analog switching techniques, an appropriate coder/decoder (CODEC), with echo cancellation, is used to transfer the audio and visual information to a CODEC in the viewing station location. The CODECs can be T1 (1.544 Mbps) CODECs for areas that cannot be reached economically at asynchronous transfer mode (ATM) data rates. This is contingent upon the diagnostic quality of the output of the T1 CODECs. Otherwise, high-speed CODECs are used with 45 Mbps DS-3 or ATM transmission facilities. This system allows full use of existing hospital infrastructures while adapting to emerging data communications infrastructures being implemented.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper proposes new optical butterfly interconnection network constructions based on the butterfly signal-flow diagrams for performing 1D and 2D fast Walsh-Hadamard transforms. We build the optical butterfly interconnection network hardware systems by using the binary phase diffraction gratings and masks. The systems are simple, regular in constructions, and easily implemented by means of gratings and masks. They relate directly optical processing with mathematical calculation, and are conveniently controlled and adjusted. These important characteristics have been verified by computer simulation.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

INTRODUCTIONFiber optic communication networks have been implemented in the commercial building and campus arena as well as innumemus strategic and ttical military applications for more than five years. Similarly, experimental prototype systems for avionicapplications have been developedand demonstrated foranumberofyears. With therecentadveinofa widely acceptedindustry fiberoptic LAN standard, FDDI, as well as advances in technology, implementation ofa high speed fiber optic communication networkin an airplane is now readily achievable with relatively low risk.The avionics market provides a challenging environment for networking equipment that has traditionally been found primarilyin benign office environments. Network implementations including Ethernet, IEEE 802.3 (either as lOBase2 or lOBaseT), IEEE802.5 (Token Ring), and FDDI are now finding applications on aircraft. The media alternatives for tbese LAN technOlOgies includecoaxial cable, unshielded and shielded twisted pair, and fiber optics. ARINC standards committees are in the process of adaptingthe various commercial networking standards to the avionics environment.Implementation of these networks is driven by the desire to enhance the following:. Transfer of data on and off the airplane (Eliminate "Sneaker Net"). Cabin services, including customer entertainment systems

Clinical acceptance of PACS is predicated upon maximum uptime. Upon component failure, detection, diagnosis, reconfiguration and repair must occur immediately. Our current PACS network is large, heterogeneous, complex and wide-spread geographically. The overwhelming number of network devices, computers and software processes involved in a departmental or inter-institutional PACS makes development of tools for network and resource management critical. The authors have developed and implemented a comprehensive solution (PACS Network-Resource Manager) using the OSI Network Management Framework with network element agents that respond to queries and commands for network management stations. Managed resources include: communication protocol layers for Ethernet, FDDI and UltraNet; network devices; computer and operating system resources; and application, database and network services. The Network-Resource Manager is currently being used for warning, fault, security violation and configuration modification event notification. Analysis, automation and control applications have been added so that PACS resources can be dynamically reconfigured and so that users are notified when active involvement is required. Custom data and error logging have been implemented that allow statistics for each PACS subsystem to be charted for performance data. The Network-Resource Manager allows our departmental PACS system to be monitored continuously and thoroughly, with a minimal amount of personal involvement and time.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A direct link between a clinical pediatric PACS module and a FONAR MRI image network was implemented. The original MR network combines together the MR scanner, a remote viewing station and a central archiving station. The pediatric PACS directly connects to the archiving unit through an Ethernet TCP-IP network adhering to FONAR's protocol. The PACS communication software developed supports the transfer of patient studies and the patient information directly from the MR archive database to the pediatric PACS. In the first phase of our project we developed a package to transfer data between a VAX-111750 and the IBM PC I AT-based MR archive database through the Ethernet network. This system served as a model for PACS-to-modality network communication. Once testing was complete on this research network, the software and network hardware was moved to the clinical pediatric VAX for full PACS integration. In parallel to the direct transmission of digital images to the Pediatric PACS, a broadband communication system in video format was developed for real-time broadcasting of images originating from the MR console to 8 remote viewing stations distributed in the radiology department. These analog viewing stations allow the radiologists to directly monitor patient positioning and to select the scan levels during a patient examination from remote locations in the radiology department. This paper reports (1) the technical details of this implementation, (2) the merits of this network development scheme, and (3) the performance statistics of the network-to-PACS interface.