Tadeusz Drwiega

Reliability and availability assessment of storage area network extension solutions

Reliability is one of the key performance metrics in the design of storage area network extensions as it determines accessibility to remotely located data sites. SANs can be extended over distances spanning from hundreds to thousands of kilometers with optical or IP-based transport networks. The network equipment used depends on the storage protocol used for the extension solution. The present article provides analytical models developed for the calculation of long-term average downtimes, service failure rates, and service availability that can be achieved as a function of hardware/software failures, software upgrades, link failures, failure recovery times, and layer 3 protocol convergence times.

Storage area network extension solutions and their performance assessment

Several solutions are proposed to extend storage area networking solutions over distances of hundreds to thousands of kilometers. Native fibre channel or end-to-end fibre channel-based solutions can be offered over long distances using SONET-based networks. Protocols such as Internet SCSI (iSCSI), Internet fibre channel protocol (iFCP) and fibre channel over TCP/IP (FCIP) are being proposed to enable storage area networking solutions over networks that use IP as their transport protocol. Performance analysis of these solutions in terms of application throughput under variable network conditions of packet loss, bandwidth availability, extension distance, and TCP implementations in the sender and receiver is presented based on analytical modeling of different solutions.

Managing Traffic Performance in Converged Networks

Invited Presentations.- Game-Theoretic Models of ISP-ISP and ISP-Customer Interactions.- Towards Autonomic Communications.- Topics in Networking Research.- Path Towards Network Convergence and Challenges.- IPTV Planning and Modeling.- Dimensioning Multicast-Enabled Networks for IP-Transported TV Channels.- Video-on-Demand Server Selection and Placement.- Analysis of the Influence of Video-Aware Traffic Management on the Performance of the Dejittering Mechanism.- Modeling of H.264 High Definition Video Traffic Using Discrete-Time Semi-Markov Processes.- Network Performance.- Initial Simulation Results That Analyze SIP Based VoIP Networks Under Overload.- Recovery, Routing and Load Balancing Strategy for an IP/MPLS Network.- Performability Analysis of Multi-layer Restoration in a Satellite Network.- Adaptive Congestion Control Under Dynamic Weather Condition for Wireless and Satellite Networks.- Routing.- Distributed Path Computation Without Transient Loops: An Intermediate Variables Approach.- A Robust Routing Plan to Optimize Throughput in Core Networks.- Stable and Robust Multipath Oblivious Routing for Traffic Engineering.- Modeling BGP Table Fluctuations.- Server/Switch Performance.- Performance Evaluation of a Reliable Content Mediation Platform in the Emerging Future Internet.- Fair Scheduling in Optical Burst Switching Networks.- Optical Packet Switches Enhanced with Electronic Buffering and Fixed Wavelength Conversion.- Impact of Complex Filters on the Message Throughput of the ActiveMQ JMS Server.- Service Overlay Networks.- Bio-inspired Analysis of Symbiotic Networks.- Hierarchical Infrastructure-Based Overlay Network for Multicast Services.- Network Capacity Allocation in Service Overlay Networks.- Hybrid Topology for Multicast Support in Constrained WDM Networks.- Traffic Source and Aggregate Models.- Understanding IP Traffic Via Cluster Processes.- State-Space Modeling of Long-Range Dependent Teletraffic.- Generating LRD Traffic Traces Using Bootstrapping.- On the Flexibility of M/G/? Processes for Modeling Traffic Correlations.- Mesh Networks - Performance Optimization - I.- Analytic Modeling of Ad Hoc 802.11 Networks with Hidden Nodes Applied to a Split Channel Solution for Performance Improvement.- Providing QoS in Ad Hoc Networks with Distributed Resource Reservation.- Fluid-Flow Modeling of a Relay Node in an IEEE 802.11 Wireless Ad-Hoc Network.- An Upper Bound on Multi-hop Wireless Network Performance.- QoS in Converged Networks.- On the Use of Accounting Data for QoS-Aware IP Network Planning.- Quantification of Quality of Experience for Edge-Based Applications.- A Comparative Study of Forward Error Correction and Frame Accumulation for VoIP over Congested Networks.- Performance Optimization of Single-Cell Voice over WiFi Communications Using Quantitative Cross-Layering Analysis.- Traffic Engineering.- A Cross-Layer Approach for Evaluating the Impact of Single NEXT Interferer in DMT Based ADSL Systems.- A Statistical Bandwidth Sharing Perspective on Buffer Sizing.- Approximating Flow Throughput in Complex Data Networks.- Improving RED by a Neuron Controller.- Mesh Networks - Performance Optimization - II.- BFGSDP: Bloom Filter Guided Service Discovery Protocol for MANETs.- Opportunistic Medium Access Control in MIMO Wireless Mesh Networks.- A Delay Based Multipath Optimal Route Analysis for Multi-hop CSMA/CA Wireless Mesh Networks.- Load Balancing by Joint Optimization of Routing and Scheduling in Wireless Mesh Networks.- End-to-End Delay in Converged Networks.- Network Calculus Delay Bounds in Queueing Networks with Exact Solutions.- Simple Approximations of Delay Distributions and Their Application to Network Modeling.- Modeling and Predicting End-to-End Response Times in Multi-tier Internet Applications.- Delay Bounds in Tree Networks with DiffServ Architecture.- Queuing Models - I.- Polling Models with Two-Stage Gated Service: Fairness Versus Efficiency.- On a Unifying Theory on Polling Models in Heavy Traffic.- Performance Analysis of a Fluid Queue with Random Service Rate in Discrete Time.- Performance of a Partially Shared Priority Buffer with Correlated Arrivals.- Performance of Peer-to-Peer Networks.- Unfairness in the e-Mule File Sharing System.- On Uncoordinated File Distribution with Non-altruistic Downloaders.- TCPeer: Rate Control in P2P over IP Networks.- Estimating Churn in Structured P2P Networks.- Performance Analysis of Peer-to-Peer Storage Systems.- Traffic Measurements and Demand Forecast.- Traffic Matrix Estimation Based on Markovian Arrival Process of Order Two (MAP-2).- Survey on Traffic of Metro Area Network with Measurement On-Line.- Deterministic Versus Probabilistic Packet Sampling in the Internet.- Simple and Accurate Forecasting of the Market for Cellular Mobile Services.- Queuing Models - II.- Performance Analysis of FEC Recovery Using Finite-Buffer Queueing System with General Renewal and Poisson Inputs.- Queueing Model with Time-Phased Batch Arrivals.- A Performance Analysis of Tandem Networks with Markovian Sources.- Queues with Message Discard at Non-zero Cost.- Impact of Convergence and Divergence Forces on Network Performance and Provisioning.- Uniform Approximations for Multirate Loss Systems with State Dependent Arrival Rates.- Power Control and Rate Adaptation in Multi-hop Access Networks - Is It Worth the Effort?.- Random Multi-access Algorithms in Networks with Partial Interaction: A Mean Field Analysis.- A Phase-Type Based Markov Chain Model for IEEE 802.16e Sleep Mode and Its Performance Analysis.- The Impact of Interference on Optimal Multi-path Routing in Ad Hoc Networks.- Modeling IEEE 802.11 in Mesh Networks.- Self-tuning Optimal PI Rate Controller for End-to-End Congestion With LQR Approach.- Quality-of-Service Provisioning for Multi-service TDMA Mesh Networks.- Provisioning Dedicated Class of Service for Reliable Transfer of Signaling Traffic.- An Algorithmic Framework for Discrete-Time Flow-Level Simulation of Data Networks.- Loss/Blocking Probability.- On the Application of the Asymmetric Convolution Algorithm in Modeling of Full-Availability Group with Bandwidth Reservation.- Analysis and Provisioning of a Circuit-Switched Link with Variable-Demand Customers.- An Approximation Method for Multiservice Loss Performance in Hierarchical Networks.- Analysis of Losses in a Bufferless Transmission Link.- Traffic Management in Wireless Networks.- Adaptive Admission Control in Mobile Cellular Networks with Streaming and Elastic Traffic.- Queueing Analysis of Mobile Cellular Networks Considering Wireless Channel Unreliability and Resource Insufficiency.- A Novel Performance Model for the HSDPA with Adaptive Resource Allocation.- Traffic Measurements and Characterization.- On the Interaction Between Internet Applications and TCP.- Measurement Based Modeling of eDonkey Peer-to-Peer File Sharing System.- Internet Data Flow Characterization and Bandwidth Sharing Modelling.- Measurement and Characteristics of Aggregated Traffic in Broadband Access Networks.- Network Design for Capacity and Performance.- Revisiting the Optimal Partitioning of Zones in Next Generation Cellular Networks: A Network Capacity Impact Perspective.- Distributed Dynamic Load Balancing in Wireless Networks.- Algorithms for Designing WDM Networks and Grooming the Traffic.- Performance Analysis of Traffic-Groomed Optical Networks Employing Alternate Routing Techniques.- Performance of Wireless Networks.- Approximating the Admission Region for Multi-resource CAC in Wireless Networks.- Co-MAC: Energy Efficient MAC Protocol for Large-Scale Sensor Networks.- Performance Evaluation of IEEE 802.11 DCF Networks.- Scheduling.- Impact of Size-Based Scheduling on Flow Level Performance in Wireless Downlink Data Channels.- A Resource Scheduling Scheme for Radio Access in Portable Internet.- Opportunistic Scheduling of Wireless Links.- Reversible Fair Scheduling: The Teletraffic Theory Revisited.- Plenary Session - Contributed Papers.- Is ALOHA Causing Power Law Delays?.- Peer-to-Peer vs. Client/Server: Reliability and Efficiency of a Content Distribution Service.- Globally Optimal User-Network Association in an 802.11 WLAN & 3G UMTS Hybrid Cell.

De-Registration Based S-CSCF Load Balancing in IMS Core Network

IP Multimedia Subsystem (IMS) provides a common control layer over which the services can be easily accessed by fixed and mobile users. In order to guarantee performance to both service providers and end service subscribers, careful management and maintenance within the control layer must be fulfilled. In this paper, we propose a solution that utilizes a controlling entity to track the utilization of hotspot Session Initiation Protocol (SIP) server (i.e., S-CSCF) and to initiate de-registration procedure so that a sufficient number of subscribers at the overloaded S-CSCF are re-associated with the other S-CSCF(s) for subsequent session services. The proposed solution redistributes and smoothes the future traffic load over individual S-CSCF in an automatic manner. The goodness of the proposal is assessed through simulations using OPNET.

Queues with message discard at non-zero cost

Some systems discard messages that wait in the queue longer than a certain threshold. Identifying such messages and discarding them takes the processor a fixed amount of time. That time is considerably smaller than an average service time, but greater than zero, therefore the models for queuing systems with reneging do not apply. This paper provides a model for such queues. It describes a method of deriving exact formulas for the distribution of waiting times, and proposes simple, yet accurate approximations. The paper then analyzes the model and discusses the properties of such systems.