Bobby Vandalore’s research while affiliated with The Ohio State University and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (50)


Figure 1: Resource management cells in an ATM network
Figure 3: Three source configuration
Figure 8: Two source configuration
On Determining the Fair Bandwidth Share for ABR Connections in ATM Networks
  • Article
  • Full-text available

March 2016

·

300 Reads

·

2 Citations

Sonia Fahmy

·

·

Shivkumar Kalyanaraman

·

[...]

·

Bobby Vandalore

In a multi-service network such as ATM, adaptive data services(such as ABR) share the bandwidth unused by higher priority services. The network indicates to the ABR sources the fair and efficient rates at which they should transmit to minimize their cell loss. In this paper, we propose a new method for determining the "effective" number of active connections, and the fair bandwidth share for each connection.

Download

General Weighted Fairness and Its Support in Explicit Rate Switch Algorithms

January 2003

·

43 Reads

·

25 Citations

Computer Communications

This paper gives a new definition of general weighted (GW) fairness and shows how this can achieve various fairness definitions, such as those mentioned in the ATM Forum TM 4.0 specifications. The GW fairness can be achieved by calculating the ExcessFairshare (weighted fairshare of the left over bandwidth) for each VC. We show how a switch algorithm can be modified to support the GW fairness by using the ExcessFairshare term. We use ERICA+ as an example switch algorithm and show how it can be modified to achieve the GW fairness. For simulations, the weight parameters of the GW fairness are chosen to map a typical pricing policy. Simulation results are presented to demonstrate that, the modified switch algorithm achieves GW fairness. An analytical proof for convergence of the modified ERICA+ algorithm is given in the appendix.


Fig. 1. Forward and backward RM cells  
Fig. 2. Scheduling of forward RM, backward RM, and data cells  
Fig. 7. Source rule 6 does not trigger if BRM flow is maintained  
Design and Simulation of Asynchronous Transfer Mode-Available Bit Rate End System Congestion Control

March 2002

·

177 Reads

·

1 Citation

SIMULATION: Transactions of The Society for Modeling and Simulation International

The authors develop a simulation model for asynchronous transfer mode available bit rate (ATM ABR) service and use it to engineer ABR congestion control behavior. Although significant work has been performed on ABR rate allocation algorithms at network switches, little work has focused on the end system behavior, which is examined in this article. The effect of (1) the speed of the links on the path from the source to the destination and (2) the connection round trip time on the selection of ABR parameter values is studied. Simulation results illustrate the impact of the key parameters that control rate reduction in the absence of network feedback on performance, in terms of connection throughputs, queue lengths at the switches, and link utilizations. These results have been incorporated into the ABR standards and can be generalized to cooperative congestion control with explicit congestion notification in the Internet.


Fig. 1. Forward and backward RM cells
Fig. 2. Scheduling of forward RM, backward RM, and data cells
Fig. 7. Source rule 6 does not trigger if BRM flow is maintained
Design and simulation of ATM-ABR end system congestion control

February 2002

·

84 Reads

·

1 Citation

We develop a simulation model for the ATM ABR service, and use it to engineer ABR congestion control behavior. Although significant work has been performed on ABR rate allocation algorithms at network switches, little work has focused on the end system behavior, which we examine in this paper. The effect of the speed of links on the path from the source to the destination, and the connection round trip time on the selection of ABR parameter values is studied. Simulation results illustrate the impact of the key parameters that control rate reduction in the absence of network feedback on performance, in terms of connection throughputs, queue lengths at the switches and link utilizations. These results have been incorporated into the ABR standards, and can be generalized to cooperative congestion control with explicit congestion notification (ECN) in the Internet.


On determining the fair bandwidth share for ABR connections in ATM networks

January 2002

Journal of High Speed Networks

In a multi‐service network such as ATM, adaptive data services (such as ABR) share the bandwidth left unused by higher priority services. The network indicates to the ABR sources the fair and efficient rates at which they should transmit to minimize their cell loss. Switches must constantly measure the demand and available capacity, and divide the capacity fairly among the contending connections. In this paper, we propose a new method for determining the “effective” number of active connections, and the fair bandwidth share for each connection. We prove the efficiency and fairness of the proposed method analytically, and use several simulations to illustrate its fairness dynamics and transient response properties.


On Determining the Fair Bandwidth Share for ABR Connections in ATM Networks

October 2001

·

30 Reads

·

23 Citations

Journal of High Speed Networks

In a multi-service network such as ATM, adaptive data services (such as ABR) share the bandwidth left unused by higher priority services. The network indicates to the ABR sources the fair and efficient rates at which they should transmit to minimize their cell loss. Switches must constantly measure the demand and available capacity, and divide the capacity fairly among the contending connections. In this paper, we propose a new method for determining the "effective" number of active connections, and the fair bandwidth share for each connection. We prove the efficiency and fairness of the proposed method analytically, and use several simulations to illustrate its fairness dynamics and transient response properties. Keywords: congestion control, fair bandwidth allocation, traffic management, ATM networks, ABR service, ERICA 1


Fair flow control for ATM-ABR multipoint connections

August 2001

·

37 Reads

·

5 Citations

Computer Communications

Multipoint-to-multipoint communication can be implemented by combining the point-to-multipoint and multipoint-to-point connection algorithms. In an ATM multipoint-to-point connection, multiple sources send data to the same destination on a shared tree. Traffic from multiple branches is merged into a single stream after every merge point. It is sometimes impossible for the network to determine any source-specific characteristics since all sources in the multipoint connection may use the same connection identifiers. The challenge is to develop a fair rate allocation algorithm without per-source accounting as this is inequivalent to per-connection or per-flow accounting in this case.We define fairness objectives for multipoint connections, and we design and simulate an O(1) fair ATM-ABR rate allocation scheme for point-to-point and multipoint connections sharing the same links. Simulation results show that the algorithm performs well and exhibits many desirable properties. We list key modifications necessary for any ATM-ABR rate allocation scheme to fairly accommodate multiple sources.


A Survey of Application Layer Techniques for Adaptive Streaming of Multimedia

June 2001

·

92 Reads

·

92 Citations

Real-Time Imaging

Though the integrated services model and resource reservation protocol (RSVP) provide support for quality of service, in the current Internet only best-effort traffic is widely supported. New high-speed technologies such as ATM (asynchronous transfer mode), gigabit Ethernet, fast Ethernet, and frame relay, have spurred higher user expectations. These technologies are expected to support real-time applications such as video-on-demand, Internet telephony, distance education and video-broadcasting. Towards this end, networking methods such as service classes and quality of service models are being developed. Today's Internet is a heterogeneous networking environment. In such an environment, resources available to multimedia applications vary. To adapt to the changes in network conditions, both networking techniques and application layer techniques have been proposed. In this paper, we focus on the application level techniques, including methods based on compression algorithm features, layered encoding, rate shaping, adaptive error control, and bandwidth smoothing. We also discuss operating system methods to support adaptive multimedia. Throughout the paper, we discuss how feedback from lower networking layers can be used by these application-level adaptation schemes to deliver the highest quality content.


Buffer management and rate guarantees for TCP over satellite‐ATM networks

February 2001

·

45 Reads

·

15 Citations

International Journal of Satellite Communications

Future broadband satellite networks will support a variety of service types. Many such systems are being design with ATM or ATM-like technology. A majority of Internet applications use TCP for data transfer. As a result, these systems must efficiently transport TCP traffic and provide service guarantees to such traffic. Several mechanisms have been presented in recent literature to improve TCP performance. Most of these can be categorized as either TCP enhancements or network-based buffer management techniques. Providing minimum rate guarantees to TCP traffic has also been suggested as a way to improve its performance in the presence of higher priority traffic sharing the link. However, the relative performance of the TCP enhancements versus the buffer management schemes has not been analyzed for long latency networks. In this paper, we address three issues. First, we present a performance analysis of TCP over satellite-ATM links using a best effort service—the ATM unspecified bit rate (UBR) service. This analysis shows that the relative impacts of buffer management, TCP policies and rate guarantees on TCP performance, depend heavily on the latency of the network. Second, we show through simulations that the buffer size required in the network for high TCP performance is proportional to the delay-bandwidth product of the network. Third, we propose a buffer management scheme called differential fair buffer allocation (DFBA) and show how it is used to implement a service that provides minimum rate guarantees to TCP traffic. An example of such a service is the ATM guaranteed frame rate (GFR) service, which is being standardized by the ATM Forum and the ITU. Copyright © 2001 John Wiley & Sons, Ltd.


The ERICA switch algorithm for ABR traffic management in ATMnetworks

March 2000

·

96 Reads

·

230 Citations

IEEE/ACM Transactions on Networking

This paper describes the “explicit rate indication for congestion avoidance” (ERICA) scheme for rate-based feedback from asynchronous transfer mode (ATM) switches. In ERICA, the switches monitor their load on each link and determine a load factor, the available capacity, and the number of currently active virtual channels. This information is used to advise the sources about the rates at which they should transmit. The algorithm is designed to achieve high link utilization with low delays and fast transient response. It is also fair and robust to measurement errors caused by the variations in ABR demand and capacity. We present performance analysis of the scheme using both analytical arguments and simulation results. The scheme is being considered for implementation by several ATM switch manufacturers


Citations (37)


... Several FBA policies based on the MMF policy [1] have been proposed as a flow/congestion control mechanism of elastic traffic and tested either in a single link or in an isolated path. In a network most studies apply the MMF, either in the domain of flow/congestion control, dealing with low-level traffic [2] or in the routing domain [3] dealing with call-level traffic. We adopt the MMF policy with min and max bandwidth requirements (BR) (we call it approximated MMF, a-MMF) as the most appropriate for elastic traffic and use a linear programming (LP) model to present it [4]. ...

Reference:

Traffic savings through a CAC procedure incorporating a fair bandwidth allocation policy for elastic services
On Determining the Fair Bandwidth Share for ABR Connections in ATM Networks

... We consider the network model shown inFigure 12. This model is adapted from the second General Fairness Configuration (GFC-2), which is specifically designed to test the max-min fairness of traffic control algorithms [29]. It consists of 22 unresponsive UDP flows, each generated by a source transmitting at a constant bit rate of 100 Mbps. ...

A Definition of Generalized Fairness and its Support in Switch Algorithms

... In this contribution, we study the performance of WWW traffic over long delay networks for the UBR+ service. In our previous work [GOYAL97a,GOYAL97b,KOTA97], we have assessed the performance of persistent TCP traffic over UBR+ for various TCP options, UBR+ drop policies, buffer sizes and link delays. In this contribution, we extend the previous studies to WWW traffic. ...

Guaranteed Rate for Improving TCP Performance on UBR+ over Terrestrial and Satellite Networks

... In following sections, we discuss the relative impact of end system policies and switch policies on the performance of satellite ATM-UBR+ networks with TCP/IP. The simulation results discussed next were first presented as a contribution [8] to Traffic Management Working Group of ATM Forum in December 1998 and partial results were published in [12]. We performed full factorial simulations [10] using a WWW traffic model (discussed next) with following parameters: TCP flavors: Vanilla (Slow Start + Congestion Avoidance) [5], Fast Retransmit Recovery (Reno) [5], NewReno [6,16] and SACK [7]. ...

Performance Analysis of TCP Enhancements for WWW Traffic using UBR+ with Limited Buffers over Satell

... The proposed algorithm is not only flexible, but also fair, fast and robust. Simulation results show that the NK algorithm is fair, and performs as well as, or better than existing mp-p traffic control schemes [10]. Furthermore, the new algorithm can be applied easily to a multipointto-multipoint (mp-mp) traffic control scheme such as the framework proposed by Ren, Siu and Suzuki [9]. ...

A switch algorithm for ABR multipoint-to-point connections
  • Citing Article

... This type is the most suitable for single FIFO implementation. Several schemes have been proposed, such as the differential fair buffer allocation (DFBA) [1] and the packet-discard push-out (PDPO) [2]. The third one belongs to the per-VC queueing class, such as the dynamic threshold -early packet discard [3] and the selective weighted fair allocation (SWFA) [4], which maintains multiple FIFO queues and relies on a weighted fair queueing (WFQ)-like scheduler to provide MCR guarantee, fair share of available bandwidth, and QoS differentiation. ...

Buffer management for the GFR service

... The data packet size is fixed to 1 kB. In order to remove limitations due to small buffer sizes on the network congestion, buffers equal to the bandwidth-delay product of the bottleneck link are used [33]. Throughput and queue size measurements are performed in intervals of 100 ms. ...

Buffer management and rate guarantees for TCP over satellite‐ATM networks

International Journal of Satellite Communications

... The evolution of cellular networks over the past few years has been astounding, from basic phone calls to fourth-generation highspeed, low-latency, and video streaming (Dike & Iddy, 2023) (Ismail et al., 2018) (Ismail et al., 2018). Due to the increasing need for multimedia applications like VoIP, multimedia online games, and video streaming, wireless communication is quickly developing (Gunasekaran et al., 2014) (Vandalore et al., 2001). One of the newest wireless broadband technologies, long term evolution (LTE), was created by the 3GPP to provide multimedia services at a higher data rate and lower latency (Elsherbiny et al., 2020;Harahap et al., 2021). ...

A Survey of Application Layer Techniques for Adaptive Streaming of Multimedia
  • Citing Article
  • June 2001

Real-Time Imaging

... It is desirable to implement a mp-mp group as a single VC for scalability and easy maintenance [13]. In addition, the following three design issues must be addressed [7,12]: (1) Bandwidth Allocation Definitions (BADs) For unicast connections, the most commonly used BAD is maxmin "fairness" [8]. The BAD becomes more complicated when mp-mp connections are involved since such a mp VC is shared by several sources. ...

Fair flow control for ATM-ABR multipoint connections
  • Citing Article
  • August 2001

Computer Communications