Scheduled System Maintenance on December 17th, 2014:
IEEE Xplore will be upgraded between 2:00 and 5:00 PM EST (18:00 - 21:00) UTC. During this time there may be intermittent impact on performance. We apologize for any inconvenience.
By Topic

Network Operations and Management Symposium Workshops, 2008. NOMS Workshops 2008. IEEE

Date 7-11 April 2008

Filter Results

Displaying Results 1 - 25 of 57
  • [Title page]

    Save to Project icon | Request Permissions | PDF file iconPDF (98 KB)  
    Freely Available from IEEE
  • [Copyright notice]

    Page(s): ii
    Save to Project icon | Request Permissions | PDF file iconPDF (91 KB)  
    Freely Available from IEEE
  • Data Inter-Working Aspect of Network Cooperation in 4G: The Case of Registry Composition in Ambient Networks

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (249 KB) |  | HTML iconHTML  

    Fourth generation networks are foreseen as coexisting and cooperating legacy (e.g. 3G networks) and new networks (e.g. mobile ad-hoc networks). Network cooperation is no novelty - roaming between 2G/3G cellular networks is just one example. However, network cooperation as envisioned for 4G goes beyond the static cooperation of today. Ambient networks are a new architectural concept for 4G networks. Network composition is a concept of ambient networks which will allow scalable and automatic cooperation between heterogeneous networks. Ambient networks can host various registries (e.g. relational databases, UDDI). When ambient networks compose, the hosted registries have to follow suit and compose. Two problems are related to registry composition: interface (i.e. protocol and APIs) inter-working and data inter-working. Data inter-working requires overcoming content heterogeneity (e.g. type, format and granularity) for giving clients a uniform access to heterogeneous data sources. This paper deals with the data inter-working aspects of network cooperation in 4G and focuses on the specific case of registry composition in ambient networks. A novel architecture is proposed, along with its architectural components and the inter-working related procedures. A proof-of-concept prototype is also described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Group-Based Protocol for Large Wireless AD-HOC and Sensor Networks

    Page(s): 7 - 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    Many routing protocols for ad-hoc networks and sensor networks have been designed, but none of them is based on groups. It is known that grouping nodes gives better performance to the group and to the whole system, thereby avoiding unnecessary message forwarding and additional overheads. We propose an approach where the network is split into several groups of sensors where connections between groups are established as a function of the proximity and the neighbor's available capacity (based on the sensor's energy). In this paper the network architecture is described with its mathematical description and the messages that are needed to proper operation. It is also simulated how much time is needed to propagate information between groups. A comparison with another group-based architectures is shown. The application areas for our proposal could be rural and agricultural environments in order to detect plagues or fires and to propagate it to neighboring areas, or for military purposes to propagate information between neighboring squads. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Provisioning Services in Multihop Cellular Networks when the End-Users Are in the Mobile Ad-Hoc Network Portion

    Page(s): 15 - 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (265 KB) |  | HTML iconHTML  

    Multihop cellular networks (MCNs) are networks that integrate a traditional 3G single-hop cellular network and a mobile ad-hoc network (MANET). They have attractive benefits, chiefly performance and flexibility. Therefore, many researches are now addressing MCNs in a variety of ways. This paper targets the service provisioning aspects in MCNs. It proposes a novel architecture that allows users in a MANET to access 3G services while the services are executed in the MANET. The benefits of this approach on the service execution process are gains in speed, load balancing, and overcoming connection difficulties between 3Gs and MANETs. The paper presents the architecture's functional entities, principles and a scenario. A prototype as a proof-of-concept is also described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • IPTV User Equipment for IMS-Based Streaming Services

    Page(s): 21 - 25
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1288 KB) |  | HTML iconHTML  

    In this paper a client side proof of concept demonstrator for the delivery of NGN-based IPTV services driven by the IPTV enabled FOKUS OpenlMS infrastructure will be presented. The so called FOKUS Media client acts as extended IMS user equipment (UE) towards the IMS infrastructure offering IPTV and common NGN services. In addition the interaction between IPTV and NGN communication services is implemented in this solution. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Novel Approach for Load Balancing in Heterogeneous Wireless Packet Networks

    Page(s): 26 - 31
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (266 KB) |  | HTML iconHTML  

    The paper aims at improving the load balancing management in coordinated heterogeneous wireless packet networks. Our main contributions are two-fold. First, we introduce a new approach for computing the network load metric based on the radio link quality and scheduling information, which can be applied to any wireless packet system. This load metric hides the radio resources heterogeneity among different integrated access technologies. Secondly, we provide a load balancing algorithm which consists of two processes: the admission control for new incoming communications and the handover enforcement for on-going ones. Numerical results prove the superiority of our proposed solution compared to other reference schemes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Index Structure Model for Mobility Management of Integrated Mobile IP Networks

    Page(s): 32 - 38
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (293 KB) |  | HTML iconHTML  

    Convergence is a key design aspect for next generation networks. Developing a general mobility management model is an important requirement for the integrated mobile IP networks. This paper begins with a survey of mobility management concept. Based on the analysis and comparison, we present a conceptual explanation of mobility management layer for mobility and its management. An index structure model is proposed to characterize mobility management schemes. In our model, we construct the basic elements of management mechanisms, i.e. node and edge, and define the main operations, namely, update operation and query operation. The fundamental performance metrics and the expressions of the cost functions is obtained. We indicate that the proposed model is flexible in its elements and parameters, and could be applied for many scenarios. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A New Mobility Solution Based On PMIP Using AAA Mobility Extensions in Heterogeneous Networks

    Page(s): 39 - 43
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (282 KB) |  | HTML iconHTML  

    Mobility access through IPv4 and IPv6 provides seamless services for the user terminals across different access networks. To provide seamless continuity while the mobile is moving from one access networks to another is provided by different mechanisms, on the whole the proposed mechanisms provides mobility with special requirements and access mechanism. Client Mobile IP (CMIP) is the most popular solution for the mobility but there are limitations and it cannot provide the total mobility solution. Proxy Mobile IP (PMIP) is a mobility mechanism to ensure mobility management of the user terminal in different access networks. This method provides the network based mobility management without any client interactions. By this method the signaling overhead and the latency during the handover and roaming is reduced. In this proposed mechanism the mobile node doesn't need to have support for the mobility instead the access network provide the mobility for the user terminal. Even though the proxy mobile IPv4 provides the mobility management there are some of the issues that have to be solved for the network controlled mobility management. In this proposed paper we proposed new mechanism using proxy mobile IP and AAA with the new mobility extensions to provide low latency handover support in heterogeneous networks. In this paper we propose this architecture with the new protocol formats and algorithms and interactions between different components of the architecture in the heterogeneous networks. We developed a testbed using WLAN, WIMAX, 3G access networks and demonstrated the capabilities of our solutions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pragmatic Approaches to True Convergence with or without IMS

    Page(s): 44 - 51
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (604 KB) |  | HTML iconHTML  

    This paper presents lessons learned from trying to address the questions of operators or communications service providers in general who try to take advantage of NGNs (next generation networks) to provide attractive and revenue generating new multimedia and/or converged services. IMS (IP Multimedia Subsystem) is often presented as the ideal solution for operators to achieve these objectives. However recently adoption of the IMS has slowed down as more and more questions about business viability are raised. In this paper we illustrate how the same objectives as what initially motivated the design or deployments plans of the IMS can be achieved with a pragmatic incremental approach that may be more business viable while at the same time allowing service providers to offer immediately IMS like services. This paper also introduces a definition for SDP (service delivery platform) and positions it with respect to IMS or NGNs. In particular we illustrate that the notion of convergence is totally decoupled from the IMS: it does not mandate the IMS and when doing so, it can in fact generalized the notions way beyond what is today seen as example of convergence. As a result we propose a pragmatic approach to target deployment of IMS-like multimedia services, IP communications networks and convergence that we believe is business viable and will facilitate adoption of IMS whenever it makes sense; while at the same time not mandating IMS.. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Enhanced FMIPv4 Horizontal Handover with Minimized Channel Scanning Time Based on Media Independent Handover (MIH)

    Page(s): 52 - 55
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (341 KB) |  | HTML iconHTML  

    In this paper we propose an enhanced MIPv4 fast horizontal handover scheme using IEEE 802.21 Media Independent Handover (MIH). This scheme enhances the L3 handover decision algorithm based on MIH provided information of available bandwidth and physical distance and minimizes L2 handover time. The handover decision algorithm is considering the overall sequence using MIHF, and based on Quality of Service (QoS) availability and location information of Mobile Node (MN). We also propose fast L2 handover scheme for horizontal handover. This scheme reduces the scanning time using the information of candidate Point of Attachment (PoA). From the simulation result we can verify the performance improvement. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multimedia Transmission over Optic, DSL and PLC Systems

    Page(s): 56 - 59
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (282 KB) |  | HTML iconHTML  

    This work presents an analysis based on an multimedia transmission generated on optical fiber backbone and two combined access technologies, PLC (Power Line Communications) and ADSL2+ (Asymmetric Digital Subscriber Line), called of pDSL. This paper points a case study of multimedia traffic using pDSL combination with intention to present measured and simulated results that prove the proposal solution viability. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ontology-Based Network Management in Seamless Roaming Architectures

    Page(s): 60 - 65
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1039 KB) |  | HTML iconHTML  

    The constant increase of the services available in data networks as well as the usage of multi-homing access networks by different service providers require a scalable and flexible interworking architecture for an efficient service delivery. Our approach consists in specifying an intermediatory architecture, RI roaming intermediatory. In this architecture, network operators manage a unique SLA (service level agreement) with the intermediate network, instead of a set of SLAs with various operators. Because of the complexity in managing several profiles, our architecture enables an ontology- based design of the operators' SLAs, users' database and configurations. A standard ontology language, W3C Web Ontology Language (OWL), is used to specify the different concepts of the roaming architecture. Also, a dedicated tool reusing standard ontology library (HP Jena API) was developed to load and create instances of existing users, SLAs and network configurations. The tool helps in quickly generating network configuration files derived from our ontology. This paper presents an ontology-based RI architecture as a solution for roaming over wireless local area network (WLAN) worldwide interoperability for microwave access (WIMAX) and 3GPP networks. To demonstrate our solution, a test-bed implementing different network technologies was setup. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Network Dimensioning Framework for QoS-guaranteed IP Networks

    Page(s): 66 - 70
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (330 KB) |  | HTML iconHTML  

    This article discusses a network planning method in a QoS-enabled IP network such as Broadband convergence Network (BcN). Since IP based networks have been developed to transport best-effort data traffic, the introduction of multi-service component in BcN requires fundamental modifications in capacity planning or network dimensioning. In this article, we present the key issues of the capacity planning in multi-service IP networks. To provide a foundation for network dimensioning procedure, we describe a systematic approach for classification and modeling of BcN traffic based on the QoS requirements of BcN services. We propose a network planning framework considering best-effort data traffic and real-time streaming traffic separately. The multi-service loss model, an extension of the conventional Erlang-B loss model, is introduced to determine required link capacity for the call-based streaming traffic. The application of multi-service loss model can provide significant improvement in network planning due to sharing of network bandwidth among different services. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • QoS-Guaranteed IPTV Service Provisioning in Home Network with IEEE 802.11e Wireless LAN

    Page(s): 71 - 76
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (389 KB) |  | HTML iconHTML  

    This paper proposes a QoS-guaranteed IPTV service provisioning by differentiated traffic handling in home network IEEE 802.11e/g Wireless LAN. The proposed traffic engineering scheme prioritizes IPTV traffic to provide guaranteed QoS in the inter-mixed and congested traffic condition. Prioritization of traffic is provided by assigning differentiated access category to each packet according to predefined QoS class. When generating multimedia video data, the IPTV server prioritizes user data by setting ToS field of IP datagram to be able to distinguish the multimedia traffic from usual best effort traffic in the home network. This paper provides detailed explanation of classification and mapping of multimedia traffic on home networks, based on access categories of IEEE 802.1 le Wireless LAN. Performance evaluations show that IPTV MPEG-2 traffic, encoded at about 2 Mbps bitrate, can be delivered with guaranteed QoS even when the aggregated traffic reaches up to 20 Mbps in IEEE 802.11e/g WLAN access point. The received video traffic has a quality that is good enough to satisfy users, and QoE(Quality of Experience) of received video is verified by VQM(Video Quality Metric). From the series of experiments, we found that the proposed differentiated traffic engineering for IPTV service can provide QoS-guaranteed real-time service in home network with Wireless LAN. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Facilitating Autonomic Management for Service Provisioning using Ontology-Based Functions & Semantic Control

    Page(s): 77 - 86
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (865 KB) |  | HTML iconHTML  

    Management of broadband convergence networks (BcN) and next generation services demands new organizational aspects also new descriptions of operations and management functions for supporting communications systems. The new organizational aspects are being engendered and supported simultaneously by the emerging information technologies and communications (ITC). This paper presents research challenges for facilitating autonomic management, defining aspects in the organizational view of service lifecycle and the control of pervasive services functions. The semantic control is done using semantic enrichment, with ontologies, for executing self- management operations and thus achieving the information interoperability necessary in pervasive applications. Ontology- based rules for service lifecycle control are presented and discussed and then a brief comparison in a management system between using policies without semantic enrichment and using ontology-based policies is depicted. The idea for supporting pervasive services and its management complexity follows the states streaked by ontology-based functions related to autonomic management principles for autonomic communications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel Available Bandwidth Estimation and Tracking Algorithm

    Page(s): 87 - 94
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (904 KB) |  | HTML iconHTML  

    The available bandwidth (AB) of an end-to-end path is its remaining capacity and it is an important metric for several applications. That's why several available bandwidth estimation tools have been published recently. Most of these tools use the probe rate model. This model is based on the concept of self- induced congestion and requires that the tools send a packet train at a rate matching the available bandwidth. The main issue with this model is that these tools congest the path under study. In this paper we present a novel available bandwidth estimation tool that takes into account this issue. Our tool is based on a mathematical model that sends packet trains at a rate lower than the AB. The main drawback of this model is that it is not able to track the AB. To solve this issue we propose to apply Kalman filters (KF) to the model. By applying these filters we can produce real-time estimations of the available bandwidth and monitor its changes. In addition the KFs are able to filter the noisy (erroneous) measurements improving the overall accuracy. We also present an extensive evaluation of our tool in different network scenarios and we compare its performance with that of pathChirp (a state-of-the-art available bandwidth estimation tool). View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • End-User IPTV Traffic Measurement of Residential Broadband Access Networks

    Page(s): 95 - 100
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (357 KB) |  | HTML iconHTML  

    Offering IPTV to broadband access subscribers is a key challenge as well as a prospective revenue source for ISPs. Despite of its growing interest, no comprehensive study has presented the traffic details of real-world commercial IPTV services yet. We have measured commercial IPTV traffic via four different residential broadband access networks, namely xDSL, Cable, FTTB, and FTTH. In this paper, we present traffic statistics and insight of the IPTV traffic impact onto these end- subscriber broadband accesses. We also present the mathematical formulas to describe traffic behavior and bandwidth demand in IPTV VoD services. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Monitor Tool for Anti-Spam Mechanisms and Spammers Behavior

    Page(s): 101 - 108
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (272 KB) |  | HTML iconHTML  

    Sending spam is a profitable activity for spammers and more than 95% of the Internet messages will be spams in a near future. This paper presents a tool that helps developers of anti-spam systems to monitor the current spammer behavior, monitor the performance of current anti-spam systems, and analyze new anti-spam mechanisms developed. Performance analyses for the mostly used anti-spam mechanisms are provided and the tool can be easily extended to analyze new anti-spam systems. Some characteristics of the processes used by the spammers to harvest electronic addresses, create the messages, and send them are also evaluated. The results show the low efficiency of the analyzed anti-spam mechanisms. Moreover, results also show important characteristics of the harvest and email sending processes, such as the high delay between the two processes and the long period of time that addresses are kept on spammers' lists. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Evaluation of Compression of Remote Network Monitoring Data Streams

    Page(s): 109 - 115
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (153 KB) |  | HTML iconHTML  

    Network monitoring and measurement is an invaluable tool for comprehending, analyzing, managing, and optimizing performance and security of networked systems. Network monitoring architectures can take the form of local or distributed deployments of sensors. Local deployments can be very precise and efficient because they benefit from fast links to the central monitoring station, but their scope can be limited to local or small-scale networks. Distributed monitoring infrastructures give a much broader view of the network state, but have the disadvantage that the amount of information they can push back to the central monitoring station is limited by the capacity of the links. In this paper we investigate the effects of compression on network monitoring data streams that are transmitted from distributed network sensors back to a central infrastructure. Our analysis shows that we can achieve very high compression rates, which means we remove much of the capacity overheads when transmitting sensor data back to the central monitors, while incurring only minimal delay in transmission of monitoring information. Our scheme also has the additional benefit of decreased CPU load at the monitoring sensor due to the aggregation of data which reduces the number of network messages. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • MonONTO: A Domain Ontology for Network Monitoring and Recommendation for Advanced Internet Applications Users

    Page(s): 116 - 123
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (309 KB) |  | HTML iconHTML  

    In order to make recommendations to users about the potential performance of advanced Internet applications - in the scope of network monitoring - it is not sufficient to just analyze the network performance metrics: it should be also considered information concerning the application type, the traffic generated, and the user profile. In the present paper, we propose a new approach for monitoring the performance of advanced Internet applications based on the use of an expert system. The expert system will infer from a domain ontology named MonONTO. This ontology amasses the main concepts and their relationships in the following sub-domains: quality of service of advanced applications, network performance measurements, and user profiles. The knowledge base, originated from MonONTO, demonstrated its use and importance in the domain described here through axioms creation and inferences performed using a specific experimental rule engine. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Packet Loss Estimation Using Distributed Adaptive Sampling

    Page(s): 124 - 131
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (167 KB) |  | HTML iconHTML  

    Packet losses are a critical metric for network performance assessment. In this paper we present a novel methodology to accurately estimate the packet loss ratio in realtime in a fully distributed scenario. The constraint such systems must face is the large amount of resources required for keeping live performance assessment. Our contribution has two main parts. On the one hand we study the behaviour of packet losses among the traffic sharing a path, and extend the classical definition of loss burst by the concept of density. On the other hand, with the knowledge acquired in the loss distribution study, we present an adaptive sampling technique that schedules the network resources in order to distributely estimate the packet losses with reasonable accuracy. In order to validate the proposal we perform some real tests over an European-wide testbed. The results show a great improvement in packet loss estimation over previous research, while using a controlled amount of resources. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Service and Network Monitoring Support for Integrated End-to-End QoS Management

    Page(s): 132 - 137
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (358 KB) |  | HTML iconHTML  

    Successful mass market provision of audio-visual services that would produce revenues for the content/service providers and network operators necessitates the use of an integrated management based on the end-to-end QoS over heterogeneous networks and terminals. This paper first briefly introduces the IST ENTHRONE II project framework for QoS- enabled multimedia contents access, where a central concept is the integrated end-to-end management. Then, the focus of the paper is to present a novel service oriented monitoring system architecture as an essential part of this management. The proposed QoS monitoring system aims at providing monitoring information to service providers for providing quantified QoS- based services and their dynamic adaptation and to network operators for dynamic resource allocation allowing better usage of network resources. Performance evaluation conducted using a test-bed shows the responsiveness and the measurements accuracy of proposed end-to-end monitoring solution. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Notice of Violation of IEEE Publication Principles
    On the Safety and Efficiency of Firewall Policy Deployment

    Page(s): 138 - 152
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (507 KB) |  | HTML iconHTML  

    Notice of Violation of IEEE Publication Principles

    "On the Safety and Efficiency of Firewall Policy Deployment,"
    by Vinoth Sivasubramaniam
    In the Proceedings of the IEEE Network Operations and Management Symposium Workshops, 2008. NOMS Workshops 2008, pp.138-152, April 2008

    After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE's Publication Principles.

    This paper is a duplication of the original text from the paper cited below. The original text was copied without attribution (including appropriate references to the original author(s) and/or paper title) and without permission.

    Due to the nature of this violation, reasonable effort should be made to remove all past references to this paper, and future references should be made to the following article:

    "On the Safety and Efficiency of Firewall Policy Deployment,"
    by Charles C. Zhang, Marianne Winslett, and Carl A. Gunter,
    in the Proceedings of the 2007 IEEE Symposium on Security and Privacy (SP07), May 2007, pp. 33-50.Firewall policy management is challenging and error-prone. While ample research has led to tools for policy specification, correctness analysis, and optimization, few researchers have paid attention to firewall policy deployment, the process where a management tool edits a firewall's configuration to make it run the policies specified in the tool. In this paper, we provide the first formal definition and theoretical analysis of safety in firewall policy deployment. We show that naive deployment approaches can easily create a temporary security hole by permitting illegal traffic, or interrupt service by rejecting legal traffic during the deployment. We define safe and most-efficient deployments, and introduce the shuffling theorem as a formal basis for constructing deployment algorithms and proving their safety. We present efficient algor- ithms for constructing most-efficient deployments in popular policy editing languages. We show that in certain widely installed policy editing languages, a safe deployment is not always possible. We also show how to leverage existing diff algorithms to guarantee a safe, most efficient, and monotonic deployment in other editing languages. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Monitoring three National Research Networks for Eight Weeks: Observations and Implications

    Page(s): 153 - 156
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (670 KB) |  | HTML iconHTML  

    With the advent of dynamic and elusive distributed applications such as peer-to-peer file sharing systems, network administrators find it increasingly difficult to understand the types of applications running in their networks and the amount of traffic each application produces. In this paper, we present measurement results from the deployment of an accurate traffic characterization application in three national research and education networks for a period of two months. Our observations go beyond traffic distribution; we explore the application usage in terms of active IP addresses, the existence of IP addresses generating massive amounts of traffic, the asymmetry of incoming and outgoing traffic, and the existence of SPAM-sending mail servers. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.