Performance aspects of the DQDB protocol

Sauer, Klaus; Schödl, Wolfgang

doi:10.1016/0169-7552(90)90033-o

Cited by 46 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the contrary, in DQDB-NS, using a slot requires issuing a request. In this case, downstream stations which are farther from the slot generator on the transmission bus will dominate the bandwidth [11,16]. Different papers have shown that DQDB-WS behaves better than DQDB-NS such as the immediate access even in heavy traffic load; but in DQDB-NS, there is no immediate access even in light traffic load.…”

Section: Dqdb and Atmimentioning

confidence: 99%

See 1 more Smart Citation

ATM LANs : New Trends and Performance Comparison

Pujolle

Jiang

Sun

1995

Local and Metropolitan Communication Systems

View full text Add to dashboard Cite

Medium access techniques for very high-speed multiaccess networks (1 Gbitls and more) are actively studied in various laboratories and standards bodies. The compatibility with the ATM technique is now required for a future homogeneity with MANs and WANs. By analysing the main ATM LANs described in the literature, this paper compares the performance of several MAC schemes. We have selected the Orwell ring with a MAC based on a slotted ring approach and a cyclic reset control mechanism. The A TMRing MAC protocol is an enhancement of the Orwell network through a new reset scheme which can achieve a less important reset overhead than Orwell. Quite different from the Orwell and ATMR networks, both DQDB and ATMi (ATM Interface) use a hybrid MAC scheme to support different classes of service, i.e., the bandwidth is divided into channels: one for the isochronous traffic and the other for the asynchronous traffic. The two sub-channels are multiplexed into the frame and may be distinguished by a special bit situated in the header of the slot. A TMi is an enhancement of RRMA (Reserved / Random Multiple Access) and DQDB-REB (DQDB with Request Balancing). A TMi supports two access modes to handle several classes of service. First mode corresponds to leased cells, based on the RRMA mechanism and the second mode provides requested cells, based on the DQDB-REB options.

show abstract

Section: Dqdb and Atmimentioning

confidence: 99%

“…This introduces the famous fairness problem on DQDB [6,11]. We introduce this situation according to the two following typical cases.…”

Section: Dqdb and Atmimentioning

confidence: 99%

ATM LANs : New Trends and Performance Comparison

Pujolle

Jiang

Sun

1995

Local and Metropolitan Communication Systems

View full text Add to dashboard Cite

show abstract

“…In the IEEE 802.6 standard DQDB protocol, the request bit is not written on the reverse 2We wish to emphasize that we deal with a model that captures some of the basic features of the DQDB system, and do not attempt to obtain an accurate portrayal of all details of DQDB. More detailed issues of this system are available in several papers [23,29,30,2,33]. Also there are several variants of this basic model which will present some performance improvements (e.g., [15,33,26,35]), and we restrict our attention to only the basic version of DQDB.…”

Section: Dqdb Modelmentioning

confidence: 99%

“…More detailed issues of this system are available in several papers [23,29,30,2,33]. Also there are several variants of this basic model which will present some performance improvements (e.g., [15,33,26,35]), and we restrict our attention to only the basic version of DQDB. ])us until the segment reaches the head of the queue.…”

Section: Dqdb Modelmentioning

confidence: 99%

“…The latter, called Distributed Queue Dual Bus (DQDB), is the subject of study in this paper; early accounts of this system (originally called QPSX) are described in [29, 3(}]. An account of the evolution of DQDB is presented in [33]. Our focus is to analyze the fairness issues of a simplified version of this system when viewed as a special type of distributed system controlled by a very simple protocol.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Average waiting time profiles of uniform DQDB model

Rao

Maly²,

Dharanikota³

et al.

Proceedings of INFOCOM '94 Conference on Computer Communications

View full text Add to dashboard Cite

3 1 Introduction 4 2 DQDB Model 7 Appendix E: Coarse Analysis for Wj(i) 30References 33 DISCLAIMERThis report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, cotopleteness, or usefulness of any information, apparatus,product, or process disclosed, or represents that its use would not infringe privately owned rights.Reference herein to any specific commercial product, process, or service by tradename, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.fl r m AbstractThe Distributed Queue Dual Bus (DQDB) system consists of a linear arrangement of N nodes that communicate with each other using two contra-flowing buses; the nodes use an extremely simple protocol to send messages on these buses. This simple, but elegant, system has been found to be very challenging to analyze. We consider a simple and uniform abstraction of this model to highlight the fairness issues in terms of average waiting time. We introduce a new approximation method to analyze the performance of DQDB system in terms of the average waiting time of a node expressed as a function of its position. Our approach abstracts the intimate relationship between the load of the system and its fairness characteristics, and explains all basic behavior profiles of DQDB observed in previous simulation. For the uniform DQDB with equal distance between adjacent nodes, we show that the system operates under three basic behavior profiles and a finite number of their combinations that depend on the load of the network. Consequently, the system is not fair at any load in terms of the average waiting times. In the vicinity of a critical load of 1 -4/N, the uniform network runs into a state akin to chaos, where its behavior fluctuates from one extreme to the other with a load variation of 2/N. Our analysis is supported by simulation results. We also show that the main theme of the analysis carries over to the general (non-uniform) DQDB; by suitably choosing the inter-node distances, the DQDB can be made fair around some loads, but such system will become unfair as the load changes.

show abstract

Performance evaluation of integrated services interworking: The ATM‐DQDB case

Venieris

Tsiotsios

Angelopoulos

1995

Int J Communication

View full text Add to dashboard Cite

Performance studies on LAN/MAN‐BISDN interworking have mainly focused on the requirements of isochronous and connectionless services. In this paper we extend performance results to cover also the case of non‐isochronous connection oriented (CO) services supported by the queued arbitrated (QA) mode of access of the DQDB protocol. Using this case we stress the more general issue of service integration impact on the interworking unit (IWU) architecture design in terms of protocol stacks and expected performance. We herein evaluate the performance of IWU architectures tailored to relay information in the lowest possible layer while implementing several service priority schemes and buffer management policies towards QoS objectives. The conditions under which the IWU design is efficient regarding performance, protocol complexity and implementation cost in this integrated services environment are identified.

show abstract

Performance aspects of the DQDB protocol

Cited by 46 publications

References 1 publication

ATM LANs : New Trends and Performance Comparison

ATM LANs : New Trends and Performance Comparison

Average waiting time profiles of uniform DQDB model

Performance evaluation of integrated services interworking: The ATM‐DQDB case

Contact Info

Product

Resources

About