Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Transport Services for Soft Real-Time Applications in IP Networks
Karlstad University, Faculty of Economic Sciences, Communication and IT.
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

In recent years, Internet and IP technologies have made inroads into almost every communication market ranging from best-effort services such as email and Web, to soft real-time applications such as VoIP, IPTV, and video. However, providing a transport service over IP that meets the timeliness and availability requirements of soft real-time applications has turned out to be a complex task. Although network solutions such as IntServ, DiffServ, MPLS, and VRRP have been suggested, these solutions many times fail to provide a transport service for soft real-time applications end to end. Additionally, they have so far only been modestly deployed. In light of this, this thesis considers transport protocols for soft real-time applications.

Part I of the thesis focuses on the design and analysis of transport protocols for soft real-time multimedia applications with lax deadlines such as image-intensive Web applications. Many of these

applications do not need a completely reliable transport service, and to this end Part I studies so-called partially reliable transport protocols, i.e., transport protocols that enable applications to explicitly trade reliability for improved timeliness. Specifically, Part I investigates the feasibility of designing retransmission-based, partially reliable transport protocols that are congestion aware and fair to competing traffic. Two transport protocols are presented in Part I, PRTP and PRTP-ECN, which are both extensions to TCP for partial reliability. Simulations and theoretical analysis suggest that these transport protocols could give a substantial improvement in throughput and jitter as compared to TCP. Additionally, the simulations indicate that PRTP-ECN is TCP friendly and fair against competing congestion-aware traffic such as TCP flows. Part I also presents a taxonomy for retransmission-based, partially reliable transport protocols.

Part II of the thesis considers the Stream Control Transmission Protocol (SCTP), which was developed by the IETF to transfer telephony signaling traffic over IP. The main focus of Part II is on

evaluating the SCTP failover mechanism. Through extensive experiments, it is suggested that in order to meet the availability requirements of telephony signaling, SCTP has to be configured much more aggressively than is currently recommended by IETF. Furthermore, ways to improve the transport service provided by SCTP, especially with regards to the failover mechanism, are suggested. Part II also studies the effects of Head-of-Line Blocking (HoLB) on SCTP transmission delays. HoLB occurs when packets in one flow block packets in another, independent, flow. The study suggests that the

short-term effects of HoLB could be substantial, but that the long-term effects are marginal.

Place, publisher, year, edition, pages
Universitetsbiblioteket, Karlstad University Press , 2006.
Series
Karlstad University Studies, ISSN 1403-8099 ; 2006:8
Keywords [en]
transport protocol, congestion control, partial reliability, soft real-time, SCTP, failover, SIGTRAN, head-of-line blocking
National Category
Computer Sciences
Research subject
Computer Science
Identifiers
URN: urn:nbn:se:kau:diva-912ISBN: 91-7063-046-1 (print)OAI: oai:DiVA.org:kau-912DiVA, id: diva2:6667
Public defence
2006-06-01, Agardhsalen, 11D 257, Karlstad university, 651 88 Karlstad, 12:40
Opponent
Supervisors
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-01-11
List of papers
1. Taxonomy and Survey of Retransmission-based Partially Reliable Transport Protocols
Open this publication in new window or tab >>Taxonomy and Survey of Retransmission-based Partially Reliable Transport Protocols
2004 (English)In: Elsevier Computer Communications, ISSN 0140-3664, Vol. 27, no 15, p. 1441-1452Article in journal (Refereed) Published
Place, publisher, year, edition, pages
Elsevier, 2004
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2119 (URN)10.1016/j.comcom.2004.04.005 (DOI)
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-08-14Bibliographically approved
2. A Simulation Based Performance Evaluation of PRTP
Open this publication in new window or tab >>A Simulation Based Performance Evaluation of PRTP
2002 (English)Report (Other academic)
Abstract [en]

PRTP is proposed to address the need of a transport service that is more suitable forapplications with soft real-time requirements, e.g., video broadcasting. It is an extensionfor partial reliability to TCP. The main idea behind PRTP is to exploit the fact thatmany soft real-time applications tolerate a limited amount of packet loss. In particular,PRTP enables an application to trade some of the reliability offered by TCP for improvedthroughput and interarrival jitter. This paper describes the design of PRTP andgives a detailed description of a simulation based performance evaluation. The performanceevaluation involved the performance of PRTP compared to TCP in long- as wellas in short-lived connections and showed that PRTP probably would give significantimprovements in performance, both in terms of throughput and interarrival jitter, for awide range of applications. The performance evaluation also suggested that PRTP is notTCP-friendly and altogether fair against competing flows and thus is not suitable for usein an environment where the main reason for packet loss is congestion, e.g., in a fixedInternet environment. We believe, however, that PRTP could be a viable alternative forwireless applications in error prone environments.

Place, publisher, year, edition, pages
Karlstad: Karlstads universitet, 2002. p. 36
Series
Karlstad University Studies, ISSN 1403-8099 ; 2002:35
Keywords
simulation, PRTP, partial reliability, retransmission based, stationary, transient, throughput, jitter, fairness, TCP-friendly
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-11841 (URN)
Available from: 2012-02-27 Created: 2012-02-27 Last updated: 2018-06-04Bibliographically approved
3. Evaluation of the QoS Offered by PRTP-ECN: A TCP Compliant Partially Reliable Transport Protocol
Open this publication in new window or tab >>Evaluation of the QoS Offered by PRTP-ECN: A TCP Compliant Partially Reliable Transport Protocol
2001 (English)In: Proceedings: IWQoS '01 Proceedings of the 9th International Workshop on Quality of Service, London: Springer , 2001, p. 217-234Conference paper, Published paper (Refereed)
Abstract [en]

The introduction of multimedia in the Internet imposes new QoS requirements on existing transport protocols. Since neither TCP nor UDP comply with these requirements, a common approach today is to use RTP/UDP and to relegate the QoS responsibility to the application. Even though this approach has many advantages, it also entails leaving the responsibility for congestion control to the application. Considering the importance of efficient and reliable congestion control for maintaining stability in the Internet, this approach may prove dangerous. Improved support at the transport layer is therefore needed. In this paper, a partially reliable transport protocol, PRTP-ECN, is presented. PRTP-ECN is a protocol designed to be both TCP-friendly and to better comply with the QoS requirements of applications with soft real-time constraints. This is achieved by trading reliability for better jitter characteristics and improved throughput. A simulation study of PRTP-ECN has been conducted. The outcome of this evaluation suggests that PRTPECN can give applications that tolerate a limited amount of packet loss significant reductions in interarrival jitter and improvements in throughput as compared to TCP. The simulations also verified the TCP-friendly behavior of PRTP-ECN

Place, publisher, year, edition, pages
London: Springer, 2001
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2121 (URN)10.1007/3-540-45512-4_16 (DOI)978-3-540-42217-4 (ISBN)
Conference
9th International Workshop on Quality of Service (IWQoS), Karlsruhe, June 2001
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
4. A Simulation Based Performance Analysis of a TCP Extension for Best Effort Multimedia Applications
Open this publication in new window or tab >>A Simulation Based Performance Analysis of a TCP Extension for Best Effort Multimedia Applications
2002 (English)In: Proceedings: 35th Annual Simulation Symposium, IEEE , 2002, p. 327-336Conference paper, Published paper (Refereed)
Abstract [en]

Since TCP is considered unsuitable for the majority of the emerging multimedia applications, these applications primarily use UDP transport together with proprietary congestion control schemes that have better jitter and throughput characteristics. A common problem with these congestion control schemes is that they often exhibit a TCP-unfriendly and unfair behavior. As the number of applications that uses this kind of schemes increases, this could become a serious threat to the stability and performance of the Internet. In an attempt to make TCP a viable alternative to some best-effort multimedia applications, we have proposed an extension to TCP - PRTP-ECN. The performance of PRTP-ECN has been compared with TCP in an extensive factorial simulation experiment. This paper gives a detailed description of this simulation experiment with an emphasis on its statistical design and analysis. The analysis of the experiment includes, among other things, a series of ANOVA tests. These tests indicate that PRTP-ECN gives significant reductions in average interarrival jitter, while at the same time leads to improvements in average throughput and goodput, and better link utilization. In addition, the analysis suggests that PRTP-ECN is almost as fair as TCP and exhibits a TCP-friendly behavior

Place, publisher, year, edition, pages
IEEE, 2002
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2122 (URN)10.1109/SIMSYM.2002.1000170 (DOI)0-7695-1552-5 (ISBN)
Conference
35th Annual Simulation Symposium (ANSS35), San Diego, April 14-18, 2002
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
5. Enhancing TCP for Applications with Soft Real-Time Constraints
Open this publication in new window or tab >>Enhancing TCP for Applications with Soft Real-Time Constraints
2001 (English)In: Multimedia systems and applications IV: 21-22 August 2001, Denver, USA / [ed] Andrew G. Tescher, Bhaskaran Vasudev, V. Michael Bove, Jr., Bellingham: SPIE , 2001, p. 18-31Conference paper, Published paper (Refereed)
Abstract [en]

Experiences in the use of the Internet as a delivery medium for multimedia-based applications have revealed serious deficiencies in its ability to provide the QoS of Multimedia Applications. We propose an extension to TCP that addresses the QoS requirements of applications with soft real-time constraints. Although, TCP has been found unsuitable for real-time applications, it can with minor modifications be adjusted to better comply with the QoS needs of applications with soft real-time requirements. Enhancing TCP with support for this group of applications is important since the congestion control mechanism of TCP assures stability of the Internet. In contrast, specialized multimedia protocols that lack appropriate congestion control can never be deployed on a large scale basis. Two factors of great importance for applications with soft real time constraints are jitter and throughput. By relaxing the reliability offered by TCP, the extension gives better jitter characteristics and an improved throughput. The extension only needs to be implemented at the receiving side. The reliability provided is controlled by the receiving application, thereby allowing a flexible tradeoff between different QoS parameters. In this paper, our TCP extension is presented and analyzed. The analysis investigates how the different application-controlled parameters influence performance. Our analysis is supported by a simulation study that investigates the tradeoff between interarrival jitter, throughput, and reliability. The simulation results also confirm that the extended version of TCP still behaves in a TCP-friendly manner

Place, publisher, year, edition, pages
Bellingham: SPIE, 2001
Series
Proceedings of the Society of Photo-Optical Instrumentation Engineers ; 4518
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2123 (URN)10.1117/12.448210 (DOI)0-8194-4242-9 (ISBN)
Conference
Covergence of Information Technologies and Communications Conference (ITCom), Denver, August 2001
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
6. Towards the Next Generation Network: The Softswitch Solution
Open this publication in new window or tab >>Towards the Next Generation Network: The Softswitch Solution
2006 (English)Report (Other academic)
Abstract [en]

Over the course of the last fifteen years, the telecommunication market has undergone dramatic changes. In the beginning of the nineties, the market essentially comprised a number of national monopolies. Today, yesterday's monopolies are under siege, and the incumbent operators face strong competition from newly established operators. Furthermore, in recent years broadband-based VoIP providers have entered the telecommunication market as worthy contenders to traditional operators. To be able to survive and thrive in this new, much more competitive, market, traditional wireless and wireline operators have to reduce their capital and operational expenditures. They also need to provide new revenue-generating applications and services. To this end, a large number

of traditional operators has replaced, or seriously consider to replace, their legacy circuit-switched fixed and cellular core networks with IP. As a first step in the migration from circuit-switched technologies to IP, the softswitch solution has evolved. This report provides a comprehensive treatment of the softswitch solution from a technical viewpoint. Additionally, the report

concludes with a brief discussion of the migration steps following the softswitch solution. In particular, an overview of the 3GPP IP Multimedia Subsystem (IMS) is given.

Place, publisher, year, edition, pages
Fakulteten för ekonomi, kommunikation och IT, 2006. p. 99
Series
Karlstad University Studies, ISSN 1403-8099 ; 2006:6
Keywords
Next Generation Networks, softswitch, signaling, SS7, Parlay, JAIN, H.323, SIP, MEGACO, H.248, SIGTRAN, IMS
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-828 (URN)91-7063-037-2 (ISBN)
Available from: 2007-05-10 Created: 2007-05-10 Last updated: 2018-06-04
7. Performance Benefits of Avoiding Head-of-Line Blocking in SCTP
Open this publication in new window or tab >>Performance Benefits of Avoiding Head-of-Line Blocking in SCTP
2005 (English)In: Autonomic and Autonomous Systems and International Conference on Networking and Services, 2005. ICAS-ICNS 2005. Joint International Conference on, IEEE , 2005, p. 44-Conference paper, Published paper (Refereed)
Abstract [en]

Mitigating the effects of head-of-line blocking (HoLB) was one of the major reasons the IETF SIGTRAN working group developed SCTP, a new transport protocol for PSTN signaling traffic, in the first place. However, studies of the impact of HoLB blocking on TCP and SCTP have given ambiguous results as to whether HoLB has, in fact, any significantly deteriorating effect on transmission delay. To this end, we have carried out a detailed experimental study on the quantitative effects of HoLB. Our study suggests that although HoLB could indeed incur a substantial delay penalty on a small fraction of the messages in an SCTP session, it has only a marginal impact on the average end-to-end transmission delay. We only observed improvements in the range of O% to 18% in average message transmission delay of using unordered delivery as compared to ordered delivery. Furthermore, there was a large variability in between different test runs, which often made the impact of HoLB statistically insignificant

Place, publisher, year, edition, pages
IEEE, 2005
Keywords
Communication industry, Computer science, Costs, Delay effects, Manufacturing, Streaming media, TCPIP, Telecommunications, Testing, Transport protocols
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2125 (URN)10.1109/ICAS-ICNS.2005.73 (DOI)0-7695-2450-8 (ISBN)
Conference
Joint International Conference on Autonomic/Autonomous Systems (ICAS) and International Conference on Networking and Services (ICNS), Tahiti, October 23-28, 2005
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
8. Performance of SCTP-controlled Failovers in M3UA-based SIGTRAN Networks
Open this publication in new window or tab >>Performance of SCTP-controlled Failovers in M3UA-based SIGTRAN Networks
2004 (English)In: Simulations Series, La Jolla, Ca: Society for Computer Simulation , 2004, p. 86-91Conference paper, Published paper (Refereed)
Abstract [en]

There are some large economic, operational, and, to some extent, technicalincentives to replace the traditional telecom network with IP. However,such a large transition will not happen overnight maybe never. Meanwhile,IP-based and traditional TDM-based telephony will have to co-exist. To addressthis situation, the IETF SIGTRAN working group has developed an architecturefor transportation of Signaling System No. 7 (SS7) traffic over IP. Still, itremains to be shown that the introduction of the SIGTRAN architecture will notsignificantly deteriorate the performance of SS7. To this end, this paperevaluates the failover performance in SIGTRAN networks. Specifically, the paperevaluates the performance of SCTP-controlled failovers in M3UA-based SIGTRAN networks.The paper suggests that in order to obtain a failover performance with SCTPcomparable to that obtained in traditional TDM-based SS7 systems, SCTP has to abandonmany of the configuration recommendations of RFC 2960 and become much more aggressivein its failover behavior. Furthermore, the paper suggests that the SCTP parameterPath.Max.Retrans has a major impact on the SCTP failover performance. Our evaluationalso indicates that for those path propagation delays envisioned in future SIGTRAN networks,the impact of the path propagation delay on the failover performance is marginal

Place, publisher, year, edition, pages
La Jolla, Ca: Society for Computer Simulation, 2004
Series
Simulations Series, ISSN 0735-9276 ; 36
Keywords
failover, SCTP, multi-homing, SIGTRAN, M3UA
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2126 (URN)
Conference
Applied Telecommunication Symposium (ATS) - Part of Advanced Simulation Technologies Conference (ASTC), Hyatt Regency Crystal City, Arlington, Virginia, April 18-22, 2004
Projects
Reliable and secure communication in SCTP
Note

Ingår i projekt1?

Ingår i projekt

Om publikationen ingår i ett projekt, ange projektets namn. För att ange flera projekt, klicka på Ytterligare projekt.

x

Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
9. Impact of Traffic Load on SCTP Failovers in SIGTRAN
Open this publication in new window or tab >>Impact of Traffic Load on SCTP Failovers in SIGTRAN
2005 (English)Conference paper, Published paper (Other academic)
Abstract [en]

With Voice over IP (VoIP) emerging as a viable alternative to the traditional circuit-switched telephony, it is vital that the two are able to intercommunicate. To this end, the IETF Signaling Transport (SIGTRAN) group has defined an architecture for seamless transportation of SS7 signaling traffic between a VoIP network and a traditional telecom network. However, at present, it is unclear if the SIGTRAN architecture will, in reality, meet the SS7 requirements, especially the stringent availability requirements. The SCTP transport protocol is one of the core components of the SIGTRAN architecture, and its failover mechanism is one of the most important availability mechanisms of SIGTRAN. This paper studies the impact of traffic load on the SCTP failover performance in an M3UA-based SIGTRAN network. The paper shows that cross traffic, especially bursty cross traffic such as SS7 signaling traffic, could indeed significantly deteriorate the SCTP failover performance. Furthermore the paper stresses the importance of configuring routers in a SIGTRAN network with relatively small queues. For example, in tests with bursty cross traffic, and with router queues twice the bandwidth-delay product, failover times were measured which were more than 50% longer than what was measured with no cross traffic at all. Furthermore, the paper also identifies some properties of the SCTP failover mechanism that could, in some cases, significantly degrade its performance

Place, publisher, year, edition, pages
Heidelberg: Springer, 2005
Series
Lecture Notes in Computer Science, ISSN 1611-3349 ; Volume 3420/2005
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2127 (URN)10.1007/978-3-540-31956-6_91 (DOI)978-3-540-25339-6 (ISBN)
Conference
ICN International Conference on Networking, Reunion, France, April 2005
Note

Ingår i projekt1?

Ingår i projekt

Om publikationen ingår i ett projekt, ange projektets namn. För att ange flera projekt, klicka på Ytterligare projekt.

x

Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved
10. Using Relaxed Timer Backoff to Reduce SCTP Failover Times
Open this publication in new window or tab >>Using Relaxed Timer Backoff to Reduce SCTP Failover Times
Show others...
(English)Manuscript (Other academic)
National Category
Computer Systems
Identifiers
urn:nbn:se:kau:diva-2128 (URN)
Available from: 2007-06-05 Created: 2007-06-05 Last updated: 2018-06-04Bibliographically approved

Open Access in DiVA

fulltext(246 kB)696 downloads
File information
File name FULLTEXT01.pdfFile size 246 kBChecksum SHA-1
224cc2671f4712ba7fdae5046e43c4e1eee7944a4c6d76a86b4c11dc0a0890bd4b2e1dbf
Type fulltextMimetype application/pdf

By organisation
Faculty of Economic Sciences, Communication and IT
Computer Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 696 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 710 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf