bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical layer survivability for single and multiple service classes
Authors: Şahin Gökhan , Azizoğlu Murat
Published: January 2025

This paper considers capacity provisioning for service and restoration in a WDM optical network which provides lightpaths to higher layer networks. An optical network will likely serve several client networks with different protection requirements from the optical layer. In this paper, a framework is developed for jointly assigning wavelengths to service and restoration paths for all failures, for traffic patterns with single or multiple classes of protection. For various restoration methods, the problem is reduced to a vertex coloring problem in a graph. We present routing and wavelength assignment algorithms for service and restoration with varying capacity/restoration time tradeoffs, and evaluate their performance through simulations. We consider three different kinds of traffic patterns in terms of protection requirement: 100% protected traffic, mixed protected/unprotected traffic, and mixed protected/low‐priority traffic. We quantify the capacity cost of protection in mixed traffic patterns as a function of the proportion ρ of the protected traffic in the mix, and identify the range of ρ where protection can be provided at low capacity penalties. This is important for assessing the economical feasibility of providing protection to a class of connections at the expense of reducing the amount of traffic that could be served without protection guarantees.
Survivability in IP over WDM networks
Authors: Vinodkrishnan Kulathumani , Chandhok Nikhil , Durresi Arjan , Jain Raj , Jagannathan Ramesh , Seetharaman Srinivasan
Published: January 2025

The Internet is emerging as the new universal telecommunication medium. IP over WDM has been envisioned as one of the most attractive architectures for the new Internet. Consequently survivability is a crucial concern in designing IP over WDM networks. This paper presents a survey of the survivability mechanisms for IP over WDM networks and thus is intended to provide a summary of what has been done in this area and help further research. A number of optical layer protection techniques have been discussed. They are examined from the point of view of cost, complexity, and application. Survivability techniques are being made available at multiple layers of the network. This paper also studies the recovery features of each network layer and explains the impact of interaction between layers on survivability. The advantages and issues of multi‐layer survivability have been identified. The main idea is that the optical layer can provide fast protection while the higher layers can provide intelligent restoration. With this idea in mind, a new scheme of carrying IP over WDM using MPLS or Multi Protocol Lambda‐Switching has been discussed. Finally, an architecture is suggested by means of which the optical layer can perform an automatic protection switch, with priority considerations with the help of signaling from the higher layers.
On the efficacy of quality, frame rate, and buffer management for video streaming across best‐effort networks
Authors: Feng Wu‐chi
Published: January 2025

In this paper, we propose a mechanism that supports the high quality streaming and adaptation of stored, constant‐quality video across best‐effort networks. The difficulty in the delivery of such traffic over best‐effort networks is the fact that both the bandwidth required from the stream and the bandwidth available across the network vary considerably over time. Our proposed approach has a number of useful features. First, it uses the a priori information from the video stream to drive that adaptation policy. Second, it does not rely on any special handling or support from the network itself, although any additional support from the network will indirectly help increase the video quality. Third, it can be built on top of TCP, which effectively separates the adaptation and streaming from the transport protocol. This makes the question of TCP‐friendliness much easier to answer. Using actual MPEG encoded video data at multiple qualities, we show through experimentation that this approach provides a viable alternative for streaming media across best‐effort networks.
Aggregation based information collection for mobile environments
Authors: Han Qi , Venkatasubramanian Nalini
Published: January 2025

In the future, we are likely to see a tremendous rise in mobile computing and communications as ubiquitous applications incorporate multimedia information. These mobile multimedia applications will have QoS requirements; resource provisioning algorithms utilize current system resource availability information to ensure that these applications meet their QoS requirements. Information collection algorithms collect and maintain current system resource information and are vital in performing efficient resource provisioning. In this paper, we present a novel information collection technique for mobile environments – the ABIC (aggregation‐based information collection) algorithm. This algorithm derives aggregate mobility from individual user mobility, then utilizes the aggregation to drive the information collection process and adjust the related parameters in the process. A feedback loop allows the information collection process to utilize feedback from the resource provisioning process in further decision making. We compare the ABIC approach to other proposed information collection algorithms under different workloads and mobility patterns. Our experimental results show that the aggregation based information collection algorithm exhibits superior performance under most mobility criteria and request patterns.
Resource optimization of CDMA systems for supporting integrated voice and data traffic
Authors: Chatterjee Mainak , Das Sajal K.
Published: January 2025

In this paper, we optimize the usage of both control and traffic channels of a CDMA system by switching the MAC states of a service. In particular, we find the optimal transition timers for a cdma2000 system supporting integrated voice and data traffic. This is achieved by optimizing a composite performance metric defined as a multi‐objective function of channel utilization, waiting time and the saving in the signalling overhead. First, we try to characterize wireless data as a mix of of Poisson‐distributed voice packets and Pareto‐distributed data packets, and study the effect of the composition of the mix and the shape parameter of Pareto distribution on the system performance. Then we derive analytical expressions for the composite performance metric with a goal to obtain the optimal values of expiration timers at which the MAC states should be switched such that the system performance is maximized. Since a closed form solution could not be obtained due to the transcendental nature of the analytical expression, simulation experiments are conducted to confirm the analysis.
Virtual source based multicast traffic routing in IP‐over‐WDM networks
Authors: Sreenath N. , Siva Ram Murthy C.
Published: January 2025

Wavelength‐division multiplexed (WDM) networks using wavelength‐routing are considered to be potential candidates for the next generation wide‐area backbone networks. At present, Internet Protocol (IP) is considered as de facto standard for transferring data in a wide‐area network. As WDM technology matures, there is a growing interest in integrated IP‐over‐WDM networks. Supporting multicasting in these networks poses a challenging topic. In IP multicast routing, only a subset of nodes may have multicast capability. The nodes that are not supporting multicast routing are by‐passed using IP tunneling concept. Because of IP tunneling, a node with optical splitting capability may not be considered while constructing a multicast tree. This results in poor bandwidth utilization. Some times, non‐delivery of data to some destinations may also happen. Hence, the IP multicast routing protocol need to consider the capabilities of the nodes. But, it may require some modifications to the existing IP multicast routing algorithms. We propose an approach, where nodes with splitting capability and wavelength conversion capability are connected and form a backbone. Hence, IP multicast routing algorithms need not consider the special capabilities of the nodes and these algorithms do not require any modifications. In multicast routing establishing a protection path is a difficult task, since the capabilities of nodes differ from each other. Using our approach it is possible to recover from a link or node failure. Also in a wide area network, delay involved in generating and establishing connections for multicast traffic is very high. In our approach, this delay is low, since it makes use of pre‐established connections (i.e., pre‐established backbone). The effectiveness of our proposed approach is demonstrated using extensive simulation experiments. The blocking performance of the proposed approach is also studied for dynamically arriving multicast sessions.
A new approach to scalable and fault‐tolerant group key management protocols
Authors: Seba H. , Bouabdallah A. , Badache N.
Published: January 2025

Secure group communication is an increasingly popular research area having received much attention in recent years. However, most existing approaches construct the group key without caring about the type of the group itself and the environment in which it evolves. This leads to inefficient solutions for real multicast groups. In this paper, we propose a new approach to enhance key management performance. In our solution, we take into consideration group characteristics. We first classify the various group characteristics and point out their influence on the efficiency of key management protocols. We, then, propose two key management protocols, which maintain good performance by adapting the key management process to the type of the group. A comparative study and simulation results evaluate the efficiency of our approach.
Security modeling and quantification of intrusion tolerant systems using attack‐response graph
Authors: Madan B.B. , Trivedi K.S.
Published: January 2025

Increasing deployment of computer systems in critical applications has made study and quantifiable analysis of the security aspects of these systems an important issue. Security quantification analysis can either be done by logging large amounts of operational data and analyzing this data or by developing analytic models. First approach, though straight forward, is less desirable, since such an analysis is typically done in a post‐facto manner, after the damage caused by a security breach has already occurred. The modeling approach, on the other hand, can be done in an a‐priori manner and is also much less costly. Another aspect of designing secure systems that is gaining acceptance is that while preventing security attacks is an important goal, it is not always possible to be able to prevent all types of attacks, particularly since attackers are always creating newer attacks. Recent approaches to designing dependable systems suggest treating intrusion prevention as a first line of defense to be followed by building intrusion tolerance measures that do not entirely preclude the possibility of security intrusion from succeeding. Such systems take appropriate responsive measures to mitigate the adverse effects of security intrusions. In this paper, we utilize the attack or privilege graph models that have been successfully used to model the attack progression to incorporate the system's response to an attack and for verifying if the system is secure or not. The proposed model is referred to as the attack response graph. Security quantification uses a Markov chain model to compute mean time taken to reach security failed states. However, getting to the Markov chain directly is rather difficult. Instead, we first obtain the SPN from the ARG description. The reachability graph of this SPN gives the absorbing state Markov chain which in turn is used to quantify the security in terms of the mean‐time‐to‐security‐failure measure for an intrusion tolerant system. Finally, we utilize sensitivity analysis to evaluate the effects of inaccuracies in estimating the model parameters.
Observing locally self-stabilization
Authors: Beauquier Joffroy , Pilard Laurence , Rozoy Brigitte
Published: January 2025

A self-stabilizing algorithm cannot detect by itself that stabilization has been reached. For overcoming this drawback Lin and Simon introduced the notion of an external observer, i.e., a set of processes, one being located at each node, whose role is to detect stabilization.

We propose here a less expensive approach, where there is a single observing process located at a unique node. This process is not allowed to detect false stabilization and it must eventually detect that stabilization is reached. Moreover it must not interfere with the observed self-stabilizing algorithm. Our result is that there exists such an observer for any problem on a distinguished network having a synchronous self-stabilizing solution. Note that our proof is constructive.
Stabilizing inter-domain routing in the Internet
Authors: Chen Yu , Datta Ajoy K. , Tixeuil Sébastien
Published: January 2025

This paper reports the first self-stabilizing Border Gateway Protocol (BGP). BGP is the standard inter-domain routing protocol in the Internet. Self-stabilization is a technique to tolerate arbitrary transient faults.

The routing instability in the Internet can occur due to errors in configuring the routing data structures, the routing policies, transient physical and data link problems, software bugs, and memory corruption. This instability can increase the network latency, slow down the convergence of the routing data structures, and can also cause the partitioning of networks. Most of the previous studies concentrated on routing policies to achieve the convergence of BGP while the oscillations due to transient faults were ignored.

The purpose of self-stabilizing BGP is to solve the routing instability problem when this instability results from transient failures. The self-stabilizing BGP presented here provides a way to detect and automatically recover from this type of faults. Our protocol is combined with an existing protocol to make it resilient to policy conflicts as well.
Hello again: Stabilization of the Hello protocol in OSPF
Authors: Cobb Jorge A. , Gouda Mohamed G. , Sidhu Deepinder
Published: January 2025

The Hello protocol in OSPF allows each router in a network to check whether it can exchange messages with neighboring routers in its network. This check is carried out by making each router periodically send hello messages to every neighboring router in the network. Associated with the Hello protocol are two time periods: the hello period and the dead period. The hello period is the time period between sending two successive hello messages to the same neighbor. The dead period is the time period after which a router can declare a neighbor dead if during this period the router does not receive any hello messages from that neighbor. The original Hello protocol restricts the hello and dead periods to be fixed over time and to be identical in all routers. Simulation studies have shown that these restrictions contribute to network instabilities and even to network collapse. To improve network stability, we present a flexible Hello protocol where the hello and dead periods change over time and become consistent (rather than identical) in all routers. To ensure the fault-tolerance of our Hello protocol, the protocol is designed to be stabilizing. That is, when started from an arbitrary initial state, the protocol converges to a legitimate state, and remains in legitimate states throughout the remainder of its execution.
Optimal snap-stabilizing PIF algorithms in un-oriented trees
Authors: Cournier Alain , Datta Ajoy K. , Petit Franck , Villain Vincent
Published: January 2025

A snap-stabilizing protocol, starting from any arbitrary initial system configuration, always behaves according to its specification. In other words, a snap-stabilizing protocol is a self-stabilizing protocol which stabilizes in zero steps. In this paper, we first prove the number of states required on processors to design a snap-stabilizing Propagation of Information with Feedback (PIF) algorithm in arbitrary un-oriented trees running under any distributed daemon (four states per processor for the middle processors and two states for each of the two extreme end processors).

Then, we propose two snap-stabilizing PIF algorithms for un-oriented trees. The former works under any (fair or unfair, central or distributed) daemon. It matches the lower bound in terms of number of states we established in this paper. The latter works under any (fair or unfair) central daemon. It uses only three states for the internal processors (two states for the root and the leaves). It is optimal in terms of number of states assuming a central daemon.

Thus, both algorithms are optimal both in terms of the stabilization time (zero steps) and state requirement per processor.
Self-stabilizing distributed file system
Authors: Dolev Shlomi , Kat Ronen I.
Published: January 2025

A self-stabilizing distributed file systems is presented. The system constructs and maintains a spanning tree for each file volume. The spanning tree consists of the servers that have volume replicas and caches for the specific file volume. The spanning trees are constructed and maintained by self-stabilizing distributed algorithms. A self-stabilizing synchronizer enforces file system semantics and consistent replications. File system updates use the tree to implement file read and write operations. A prototype of the system based on the Linux operating system has been implemented.
Transformations of self-stabilizing algorithms
Authors: Ioannidou Kleoni
Published: January 2025

In this paper, we are interested in transformations of self-stabilizing algorithms from one model to another that preserve stabilization. We propose an easy technique for proving correctness of a natural class of transformations of self-stabilizing algorithms from any model to any other. We present a new transformation of self-stabilizing algorithms from a message passing model to a shared memory model with a finite number of registers of bounded size and processors of bounded memory and prove it correct using our technique. This transformation is not wait-free, but we prove that no such transformation can be wait-free. For our transformation, we use a new self-stabilizing token-passing algorithm for the shared memory model. This algorithm stabilizes in O(nlog 2n) rounds, which improves existing algorithms.
Stabilizing causal deterministic merge
Authors: Kulkarni Sandeep S. , Ravikant
Published: January 2025

In this paper, we focus on causal deterministic merge – that combines causal delivery and uniform total order – in semi-synchronous publish-subscribe systems that provide simple guarantees related to clock values and message delays. We consider two properties of the timestamps used to obtain causal deterministic merge: (1) they should be bounded, i.e., for a given system, the maximum size of the timestamp should be independent of the length of the computation, and (2) they should be scalar, i.e., the time required to compare/update timestamps should be independent of the size of the system. By making certain assumptions about how the timestamps are compared, we show that it is impossible to obtain a solution that uses scalar and bounded timestamps. Hence, we focus on solutions that achieve one of these properties. We present two solutions where the size of the timestamps is bounded; the size of the timestamps in the first solution is logarithmic in the number of processes whereas in the second solution, it is linear in the number of processes. We also present a solution where the timestamp consists of O(1) integers that can grow unbounded; we further show that the timestamps in this solution can be bounded if the application provides a simple guarantee about event creation. Each of these solutions is stabilizing fault-tolerant in that even if the system is perturbed by faults that improperly initialize processes, lose/corrupt messages and temporarily violate system guarantees, the system recovers to states from where subsequent computation satisfies the requirements of causal deterministic merge.

Our solutions improve previously known solutions in several ways: In previous solutions, the timestamps consist of O(n2) unbounded integers where n is the number of processes. By contrast, one of our solutions uses O(1) unbounded integers and the remaining three solutions use bounded integers.
Formal design of self-stabilizing programs
Authors: Prasetya I.S.W.B. , Swierstra S.D.
Published: January 2025

Distributed algorithms, self-stabilizing systems in particular, are often too delicate to be argued informally. Formal proofs are much more reliable, but unfortunately are often long and complicated. Some of the complication is inherent, but some is also the result of poor notation and formalism which is not abstract enough. Improving them would make formal proofs easier to write and to understand, which will also make them less error prone. In this spirit, this paper proposes an extension of the logic UNITY with a number of new operators to model self-stabilization and a formalization of a number of useful design strategies. They should enhance the formalism offered by UNITY with better abstraction to specify and reason about self-stabilization.
On modeling and tolerating incorrect software
Authors: Arora Anish , Theimer Marvin
Published: January 2025

Distributed systems have to deal with the following scenarios in practice: bugs in components; incorrect specifications of components and, therefore, incorrect use of components; unanticipated faults due to complex interactions or to not containing the effects of faults in lower-level components; and evolution of components. Extant fault tolerance models deal with such scenarios in only a limited manner. In particular, we point out that state corruption is inevitable in practice and that therefore one must accept it and seek to correct it.

The well-known concepts of detectors and correctors can be used to find and repair state corruption. However, these concepts have traditionally been employed to immediately detect and correct errors caused by misbehaving system components. Immediate detection and correction is often too expensive to perform and hence we consider the implications of running detectors and correctors only intermittently.

More specifically, we address issues that must be dealt with when state corruption may persist within a system for a period of time. We show how to both detect and correct state corruption caused by infrequently occurring “transient” errors despite the ability for it to actively spread to other parts of the system. We also show how to eventually detect all state corruption, even in cases where continually recurring errors are constantly introducing new state corruption. Finally, we discuss the minimum set of capabilities needed from a trusted base of software in order to guarantee the correctness of our algorithms.
Dispersion compensation in IP-over-DWDM networks employing combined modulation formats
Authors: André P.S. , Teixeira A.L.J. , Monteiro P. , Lima M.J.N. , Nogueira R.N. , da Rocha F. , Pinto J.L.
Published: January 2025

In this work we report a study on dispersion compensation for combined FSK/ASK modulation formats. These combined modulation formats have been proposed recently for optically labeling of high speed IP packets through DWDM networks. Numerical simulation was used to optimize the transmission characteristics in terms of extinction ratio for the ASK signal, injected optical power and dispersion compensation ratio. We also demonstrate experimentally a transmission of a 155 Mbit/s FSK combined with a 10 Gbit/s ASK signal over 20 km of uncompensated SMF fiber with 1.3 dB power penalty, showing the possible application of this technique for photonic IP routing.
Power Control technique for High Speed Downlink Packet Access system
Authors: Mousa Anwar
Published: January 2025

In this paper a Power Control technique for the High Speed Downlink Packet Access (HSDPA) system is proposed and compared to the UMTS-standard technique. In addition to compensating the propagation losses (distance-loss, shadowing and fast fading), the proposed technique adapts the signal-to-cochannel interference ratio (C/I) to be in the required range. The power control algorithm uses a predefined C/I threshold (C/I_th) specific for each service and data rate. When the measured C/I of the user equipment is above (lower) than the C/I_th, the decrease (increase) of power is ordered adaptively depending on the difference between the two values. The two techniques were evaluated by simulation in the framework of the project IST-FITNESS (IST-2000-30116, Fourth-generation Intelligent Transparent Networks Enhanced through Space-time Systems), where an effective software platform simulating the HSDPA network was developed. The numerical results quantitatively outline the benefits on system performance, for each technique, achieved in terms of average transmitted power and outage probability of C/I versus velocity.
Design, implementation and evaluation of resource management system for Internet servers
Authors: Azuma Kazuhiro , Okamoto Takuya , Hasegawa Go , Murata Masayuki
Published: January 2025

A great deal of research has been devoted to solving the problem of network congestion posed against the context of increasing Internet traffic. However, there has been little concern regarding improvements in the performance of Internet servers such as Web/Web proxy servers in spite of the projections that the performance bottleneck will shift from networks to endhosts. In this paper, we propose a new resource management scheme for Web/Web proxy servers, which manages their resources for TCP connections, effectively and fairly. In the proposed system, we focus on the effective use of server resources by assigning dynamically the send/receive socket buffer according to the required size of each TCP connection, and terminating positively the idol persistent connection. Also, we validate the effectiveness of our proposed scheme through simulation and implementation experiments, and confirm conclusively that Web/Web proxy server throughput can be improved by 25% at maximum, and document transfer delay perceived by client hosts can be decreased by up to 90%.
On deflection routing in optical burst-switched networks
Authors: Hsu Ching-Fang , Liu Te-Lung
Published: January 2025

This paper investigates the performance of deflection routing in optical burst-switched networks adopting Just-Enough-Time (JET) signaling mechanism. In general, buffer requirement is not vital for JET-based optical burst switching (OBS). However, if deflection routing is enabled, optical buffers are indispensable to prevent data bursts from overtaking associated control packets. Another solution, which can alleviate buffering, is to lengthen offset time in the beginning. As previous work indicated, a burst with extra offset time has higher priority than that without extra offset time and quality-of-service (QoS) can be accomplished in this way. In this paper, we consider the performance of deflection routing in both non-prioritized and prioritized JET-based optical burst-switched networks. For each case, a variant of priority queuing model is proposed to approximate burst loss probability respectively and the results show that the model provides an accurate estimation. We also evaluate the performance of deflection routing with and without QoS support in arpanet-2 topology.
SCIT-DNS: Critical infrastructure protection through secure DNS server dynamic updates
Authors: Huang Yih , Arsenault David , Sood Arun
Published: January 2025

Domain Name Systems (DNS) provide the mapping between easily remembered host names and their IP addresses. While domain name information is typically created and updated off-line, dynamic DNS updates allow clients to manage domain names online, in real time. The current secure DNS standards (DNSSEC) require private keys to be kept online to sign dynamic updates, leaving private keys subject to network-based attacks.

In this work, we develop a secure implementation framework of DNS servers that voids the above requirement. Our approach, called Self-Cleansing Intrusion Tolerance (SCIT), strengthens DNSSEC through hardware redundancy. Our system uses a highly integrated cluster of DNS servers that constantly rotates the role of individual servers, handles one-server failures gracefully, confines the damages of successful intrusion to a limited time, and digitally signs dynamic updates by a clean server using the DNS zone key while keeping the key offline at all times. It is our belief that the availability and integrity of critical communications infrastructure, such as DNS, far outweigh the costs of hardware redundancy.

In this paper, we present (1) the architecture of SCIT DNS clusters that achieves the above goals, (2) a secure Cluster Coordination Protocol (CCP) that servers in the cluster use to coordinate role changes without ever opening a port, and (3) the designs of our ongoing SCIT DNS cluster prototype. Preliminary experiences of our prototype show that role rotation and self-cleansing cycles are in the range of minutes, restricting the damages of even undetected but successful attacks to short time windows.
SPEE: A Secure Program Execution Environment tool using code integrity checking
Authors: Gelbart Olga , Narahari Bhagirath , Simha Rahul
Published: January 2025

With the growing number of successful computer attacks, especially those using the Internet and exploiting software vulnerabilities, software protection has become an important issue in computer security. This paper proposes a system – SPEE – for software integrity protection and authentication and presents performance results. Our system architecture utilizes key components from the compilation process as well as operating system support to provide static verification of executables. Code integrity checking is performed by means of a hierarchical hashing scheme, which not only detects changes but also efficiently isolates them. This scheme provides a higher level of protection against code injection or modification than a simple chaining of the program blocks. As an additional benefit, it also provides forensic information in case of a verification failure by providing the user with information about which part of the program has been modified. The SPEE tool is designed to function as part of the operating system kernel in order to provide a trusted computing system.
AR-TCP: A Loss-Aware Adaptive Rate based TCP for Ad hoc Wireless Networks
Authors: Venkata Ramana B. , Manoj B.S. , Siva Ram Murthy C.
Published: January 2025

Transmission Control Protocol (TCP), the de-facto protocol for reliable transport over the Internet, does not perform well over Ad hoc Wireless Networks (AWNs). The reasons are as follows. The bursty transmissions made by TCP often lead to congestion in the AWNs which further result in a high packet loss. Another reason is the TCP's inability of distinguishing congestion losses from wireless losses, as a result of which, it invokes the congestion control mechanism for both cases. In order to address these problems, we propose Loss-Aware Adaptive Rate based TCP (AR-TCP), which does the rate-based transmission of TCP segments and also maintains compatibility with TCP. By making a few changes to TCP code, AR-TCP is implemented as a small controller called Adaptive Transport Controller (ATC) that works just below TCP. The ATC adapts to the state of the network, using the feedback about end-to-end data rate and quality of the path of a TCP flow. The ATC schedules the data segments, which are received from TCP, according to the end-to-end data rate. When a path break is predicted, ATC pushes TCP into FREEZE state, in which TCP does not transmit any segments; thus avoids unnecessary re-transmissions and re-transmission timeouts (RTOs). Since the segments are transmitted based on the end-to-end data rate, a TCP flow experiences fewer number of congestion situations, which minimizes the packet loss due to congestion. The rate-based transmission also helps in improving the fairness at MAC layer. Extensive simulations were performed to assess the performance of the AR-TCP under varying network conditions. The simulation results clearly indicate the gain (upto 71%) in the throughput of AR-TCP and also significant reduction (upto 70%) in the packet loss compared to those of TCP.
A novel collusion-resilient architecture for secure group communication in wireless ad-hoc networks
Authors: Moharrum M. , Mukkamala R. , Eltoweissy M.
Published: January 2025

Current architectures for secure group communication schemes have been designed with both the Internet and network-level multicast as an underlying infrastructure. However, such schemes may not be suitable for wireless ad-hoc networks (WAHNs) which are now increasingly being used in several information sensitive applications. In this paper, we propose a novel architecture for secure group communication in WAHNs with no network-level multicast support. For improved efficiency and scalability, our architecture integrates secure multicast functions with group management tasks at the application layer. The architecture consists of key generation and key distribution schemes, which we developed in an earlier work. Here, we introduce a new collusion resistant key assignment protocol for a clustered WAHN. We show its implementability, scalability for communication and storage costs, and suitability for WAHNs.
On autonomic optimization of firewall policy organization
Authors: Hamed Hazem , Al-Shaer Ehab
Published: January 2025

Security policies play a critical role in many of the current network security technologies such as firewalls, IPSec and IDS devices. The configuration of these policies not only determines the functionality of such devices, but also substantially affects their performance. The optimization of filtering policy configuration is critically important to provide high performance packet filtering particularly for high speed network security.

Current packet filtering techniques exploit the characteristics of the filtering policies, but they do not consider the traffic behavior in optimizing their search data structures. This often results in impractically high space complexity, which undermines the performance gain offered by these techniques. Also, these techniques offer upper bounds for the worst case search times; nevertheless, the more common average case scenarios are not necessarily optimized. Moreover, the types of packet filtering fields used in most of these techniques are limited to IP header fields and cannot be generalized to cover transport and application layer filtering.

In this paper, we present a novel technique that utilizes Internet traffic characteristics to optimize the organization of firewall policies. The proposed technique timely adapts to the traffic conditions using actively calculated statistics to dynamically optimize the ordering of packet filtering rules. The rule importance in traffic matching as well as its dependency on other rules are both considered in our optimization algorithm. Through extensive evaluation experiments using simulated and real Internet traffic traces, the proposed mechanism is shown to be efficient and easy to deploy in practical firewall implementations.
Reconfiguring Role Based Access Control policies using risk semantics
Authors: Aziz Benjamin , Foley Simon N. , Herbert John , Swart Garret
Published: January 2025

We present a refined model for Role Based Access Control policies and define a risk measure for the model, which expresses elements of the operational, combinatorial and conflict of interest risks present in a particular policy instance. The model includes risk-reducing mechanisms corresponding to practical mechanisms like firewalls, stack checking, redundancy, and event tracking that are frequently used to reduce risks in real systems. We also define policy transformation operators that produce new policies that allow the behaviours of the old policy while potentially reducing the risk measure. Sequences of these operators can be used to find policies that are less risky but still implement the initial policy. An example is give for Grid computing.
Supporting heterogeneous middleware security policies in WebCom
Authors: Foley Simon N. , Mulcahy Barry P. , Quillinan Thomas B. , O'Connor Meabh , Morrison John P.
Published: January 2025

With the growing interest in service-oriented architectures, achieving seamless interoperability between heterogeneous middleware technologies has become increasingly important. While much work investigating functional interoperability between different middleware architectures has been reported, little practical work has been done on providing a unified and/or interoperable view of security between the different approaches.

In this paper we describe how the Secure WebCom distributed architecture provides access control policy interoperability support between a number of middleware security architectures. Secure WebCom uses the KeyNote trust management system to help coordinate the trust relationships between the different middleware systems and their associated access control policies. Middleware authorisation policies can be encoded in terms of cryptographic certificates, and vice-versa. This provides a unified view of access control across heterogeneous middleware systems and also provides the basis for decentralised support of middleware access control policies.
Specifying and enforcing a multi-policy paradigm for high assurance multi-enclave systems
Authors: Wahsheh Lu'ay A. , Alves-Foss Jim
Published: January 2025

One fundamental key to successful implementation of secure high assurance computer systems is the design and implementation of security policies. For systems enforcing multiple concurrent policies, the design and implementation is a challenging and difficult task. To simplify this task, we present an Inter-Enclave Multi-Policy (IEMP) paradigm for information access of the Multiple Independent Levels of Security and Safety (MILS) approach to high assurance system design for security- and safety-critical multi-enclave systems. The IEMP paradigm manages multiple security policies (i.e., controls the conflicts and cooperation of policies of different enclaves) within heterogeneous systems. IEMPs are “policies about policies” that ensure the enforcement of end-to-end mandatory information flow security policies, where the management and evolution of policies can be separated from applications. Although the approach was initially designed for use in the MILS architecture, based on the concept of a separation kernel, it is applicable to a much broader range of architectures.
International Internet2 connectivity and performance in medical imaging applications: Bridging the Americas to Asia
Authors: Liu Brent J. , Zhou Zheng , Gutierrez Marco A. , Documet Jorge , Chan Lawrence , Huang H.K.
Published: January 2025

Internet-2 is an advanced high-speed computer network, which has been widely used for medical imaging applications such as teleradiology and teleconsultation. Internet-2 can fulfill the requirements for high-speed data transmission and short turn-around time with low operation cost once installed. However, high performance may not necessarily be retained for global access from international network peers as well as commercial Internet Service Provider (ISP) solutions. This paper describes the methodology of establishing international Internet-2 connections between three different internationally linked sites: the Imaging Processing and Informatics (IPI) Laboratory, University of Southern California, Los Angeles, California; the Hong Kong Polytechnic University (PolyU), Hong Kong, and the Heart Institute (InCor) of the University of São Paulo, Brazil. Two major factors will be discussed including network looping in the US and bottleneck of the connection, raising the round-trip time and limiting the available bandwidth respectively.

In addition to the three site International Internet2 Connectivity, a consistent and repeatable tuning protocol for international Internet2 applications in the clinical environment will be presented. The experimental results of the FTP and DICOM transmission using the automatic tuning protocol at both sending and receiving sites will be presented and compared with results for the combinations where this protocol is used at either one site only or no site at all in order to demonstrate the improvement in overall network throughput by this proposed tuning method. These performance numbers will also be compared to commercially available ISP connections to further show the differences between International Internet-2 and its ability to support medical imaging applications.
The role of a Data Grid in worldwide imaging-based clinical trials
Authors: Zhou Z. , Gutierrez M. , Documet J. , Chan L. , Huang H.K. , Liu B.
Published: January 2025

Clinical trials play a crucial role in testing new drugs or devices in modern clinical practice. Medical imaging has become an important tool in clinical trials because images provide a unique and fast diagnosis with visual observance and quantitative assessment. A typical imaging-based clinical trial consists of: (1) A well-defined rigorous clinical trial protocol, (2) a radiology core that has a quality control mechanism, a biostatistics component, and a server for storing and distributing data and analysis results; and (3) many field sites that generate and send clinical trial image studies to the radiology core. With ever-increasing number of clinical trials, it becomes a great challenge for a radiology core which handles multiple clinical trials to have a robust server to administrate multiple trials as well as satisfy the requirements to quickly distribute information to participating radiologists/clinicians worldwide to assess trials' results. Data Grid in the grid computing technology can satisfy the aforementioned requirements of imaging-based clinical trials. In this paper, we present a Data Grid architecture for worldwide imaging-based clinical trials. The Data Grid testbed has been set up in three international sites: Image Processing and Informatics (IPI) Laboratory at University of Southern California, USA; the Hong Kong Polytechnic University; and InCor (Heart Institute) at Sao Paulo, Brazil. The three chosen sites are connected with high speed international networks including the Internet2, the HARNET (Hong Kong Academic and Research Network), and the Brazilian National Research and Education Network (RNP2). The concept, design and implementation of the Data Grid are presented. Grid computing technology open source software Globus Toolkit 4.0 and DICOM technology were used to implement the DICOM compliance Data Grid. This paper also describes results of using Data Grid in imaging-based clinical trails for fault tolerance image data backup. The successful implementation and evaluation of the Data Grid for imaging-based clinical trials provide three major benefits: (1) an understanding of the methodology for using data grid technology and high speed networks in clinical trails; (2) an establishment of the performance benchmarks of Data Grid over high speed networks; and (3) a Data Grid test bed for performing worldwide imaging based clinical trials.
A tree-based scheme for security of many-to-many communications
Authors: Lin Ren-Hung , Jan Jinn-Ke
Published: January 2025

In many-to-many group secure communications, group members may broadcast or receive messages during any session. A fast session key distribution scheme is desirable for handling highly changeable message flows among group members. In this paper, we propose a group keying scheme using tree structures for many-to-many group secure communications. The key storage and computational complexity of the proposed scheme are acceptable and practical for real-life applications. Moreover, once keys are distributed, group members will be able to freely communicate with any member in security with no need of a group controller.
Towards design of a nailfold capillary microscopy image analysis and diagnosis framework using grid technology
Authors: Li Kuan-Ching , Chen Chiou-Nan , Hsieh Tsu-Yi , Wen Chia-Hsien , Lan Joung-Liang , Chen Der-Yuan , Tang Chuan-Yi
Published: January 2025

Nailfold capillary microscopy examination has been used since late 1950s as a non-invasive in-vivo technique for diagnosing and monitoring connective tissue disease in adults. Disorders such as Primary Raynaud's phenomenon, progressive systemic sclerosis, and rheumatoid arthritis were detected in more than 80% of adult patients, by analyzing such high resolution images. Internet computing and grid technologies have changed the way we tackle complex scientific problems. Grid computing environments are characterized by interconnecting a number of heterogeneous resources in geographically distributed domains. They enable large-scale aggregation and sharing of computational, data and other resources across institutional boundaries. In this paper, we discuss and develop a framework for nailfold capillary microscope image acquisition and analysis, using computational power provided by grid platforms. In this way, not only useful medical information can be extracted from large amount of history anamneses in an efficient way, with the use of a number of adequate techniques and methods in high performance computing, but also to diagnose abnormal nailfold capillary in far shorter time, to diagnose patient's disease in real-time basis. Based on the results of the classification, analysis of history anamneses are done to discover updated health information possibly hidden in patients' medical records.
Understanding of human behaviors from videos in nursing care monitoring systems
Authors: Liu Chin-De , Chung Pau-Choo , Chung Yi-Nung , Thonnat Monique
Published: January 2025

This paper addresses the issue in scenario-based understanding of human behavior from videos in a nursing care monitoring system. The analysis is carried out based on experiments consisting of single-state scenarios and multi-state scenarios where the former monitors activities under contextual contexts for elementary behavior reasoning, while the latter dictating the elementary behavior order for behavior reasoning, with a priori knowledge in system profile for normality detection. By integrating the activities, situation context, and profile knowledge we can have a better understanding of patients in a monitoring system. In activity recognition, a Negation-Selection mechanism is developed. which employs a divide-and-conquer concept with the Negation using posture transition to preclude the negative set from the activities. The Selection that follows the Negation uses a moving history trace for activity recognition. Such a history trace composes not only the pose from single frame, but also history trajectory information. As a result, the activity can be more accurately identified. The developed approach has been established into a nursing care monitoring system for elder's daily life behaviors. Results have shown the promise of the approach which can accurately interpret 85% of the regular daily behavior. In addition, the approach is also applied to accident detection which was found to have 90% accuracy with 0% false alarm.