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unified end-to-end priority strategy for traffic control in an ATM-based broadband ISDN

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Date Issued:
1993
Summary:
In order to guarantee a committed Quality of Service (QoS) to the users of a Broadband Integrated Services Digital Network (B-ISDN), preventive congestion control becomes critical, and is implemented through Call Acceptance Control (CAC) and Usage Parameter Control (UPC) functions. Currently, Asynchronous Transfer Mode (ATM) cells are equipped with a 1-bit Cell Loss Priority (CLP) field, which can be used for service-oriented and/or UPC marking. This creates a conflict, since these two marking approaches may have contradicting objectives, and are designed to operate independently. Moreover, by admitting excessive cells as marked traffic, this group is allowed to grow uncontrollably, thereby jeopardizing the QoS committed to other marked cells. This dissertation presents a solution to these problems by proposing a new 4-class priority strategy that unifies the two marking approaches, and is based on a 2-bit CLP field. The impacts of the new priority scheme are triple-fold: (I) For the UPC, a new scheme, the Forgiving Leaky Bucket (FLB), not only carries priorities through subnetwork boundaries, but also has the power of unmarking, i.e. forgiving, previously marked cells, depending on the bandwidth availability in the entering subnetwork. Forgiving will correct access-point bias, a phenomenon observed in internetworked ATM subnetworks of different congestion conditions. (II) At ATM switching nodes, a new space priority scheme is based on a hybrid of the Nested Threshold, and Push-Out cell discarding methods. This scheme is designed for the 4-class priority strategy, and improves the quality of the low priority traffic. (III) In interfacing High Speed Local Area Networks and Metropolitan Area Networks, idle bandwidth due to STM multiplexing is utilized to carry marked excessive cells of connection-oriented variable bit rate traffic, in addition to the service-oriented marking performed at transmitting stations. The resulting stream is then carried through internetworking points, subject to FLB adjustments. As a result, the STM and ATM subnetworks will support a uniform end-to-end priority strategy, essential for a B-ISDN. The proposed impacts are analyzed and compared with conventional implementations, and future directions are indicated.
Title: A unified end-to-end priority strategy for traffic control in an ATM-based broadband ISDN.
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Name(s): Bemmel, Vincent Egbert.
Florida Atlantic University, Thesis advisor
Ilyas, Mohammad, Thesis advisor
College of Engineering and Computer Science
Department of Computer and Electrical Engineering and Computer Science
Type of Resource: text
Genre: Electronic Thesis Or Dissertation
Issuance: monographic
Date Issued: 1993
Publisher: Florida Atlantic University
Place of Publication: Boca Raton, Fla.
Physical Form: application/pdf
Extent: 141 p.
Language(s): English
Summary: In order to guarantee a committed Quality of Service (QoS) to the users of a Broadband Integrated Services Digital Network (B-ISDN), preventive congestion control becomes critical, and is implemented through Call Acceptance Control (CAC) and Usage Parameter Control (UPC) functions. Currently, Asynchronous Transfer Mode (ATM) cells are equipped with a 1-bit Cell Loss Priority (CLP) field, which can be used for service-oriented and/or UPC marking. This creates a conflict, since these two marking approaches may have contradicting objectives, and are designed to operate independently. Moreover, by admitting excessive cells as marked traffic, this group is allowed to grow uncontrollably, thereby jeopardizing the QoS committed to other marked cells. This dissertation presents a solution to these problems by proposing a new 4-class priority strategy that unifies the two marking approaches, and is based on a 2-bit CLP field. The impacts of the new priority scheme are triple-fold: (I) For the UPC, a new scheme, the Forgiving Leaky Bucket (FLB), not only carries priorities through subnetwork boundaries, but also has the power of unmarking, i.e. forgiving, previously marked cells, depending on the bandwidth availability in the entering subnetwork. Forgiving will correct access-point bias, a phenomenon observed in internetworked ATM subnetworks of different congestion conditions. (II) At ATM switching nodes, a new space priority scheme is based on a hybrid of the Nested Threshold, and Push-Out cell discarding methods. This scheme is designed for the 4-class priority strategy, and improves the quality of the low priority traffic. (III) In interfacing High Speed Local Area Networks and Metropolitan Area Networks, idle bandwidth due to STM multiplexing is utilized to carry marked excessive cells of connection-oriented variable bit rate traffic, in addition to the service-oriented marking performed at transmitting stations. The resulting stream is then carried through internetworking points, subject to FLB adjustments. As a result, the STM and ATM subnetworks will support a uniform end-to-end priority strategy, essential for a B-ISDN. The proposed impacts are analyzed and compared with conventional implementations, and future directions are indicated.
Identifier: 12334 (digitool), FADT12334 (IID), fau:9236 (fedora)
Collection: FAU Electronic Theses and Dissertations Collection
Note(s): College of Engineering and Computer Science
Thesis (Ph.D.)--Florida Atlantic University, 1993.
Subject(s): Integrated services digital networks
Broadband communication systems
Computer networks--Management
Packet switching (Data transmission)
Held by: Florida Atlantic University Libraries
Persistent Link to This Record: http://purl.flvc.org/fcla/dt/12334
Sublocation: Digital Library
Use and Reproduction: Copyright © is held by the author, with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Use and Reproduction: http://rightsstatements.org/vocab/InC/1.0/
Host Institution: FAU
Is Part of Series: Florida Atlantic University Digital Library Collections.