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
Error and Traffic Control for High-Speed Networks
KTH, School of Electrical Engineering (EES).
2005 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

The Internet evolves rapidly, both in terms of the applications that use it and the networks that carry the traffic. This creates many important research tasks, both to adapt the networks that carry the traffic to work well together with the Internet protocols and to make the protocols robust to tolerate various underlying networks. A key issue is error handling, in this thesis both error correction for both underlying optical networks and integrated in the Internet protocols are studied. The results show that error control should not be considered in isolation: by combining it with traffic control we find that it is possible to implement new services in elegant ways that are well suited for deployment in the Internet.

The traffic in the Internet is increasingly being carried over optical links which offer large capacity. When optical fibers are deployed in access networks, the components need to be cheap and an important factor is sharing of the fibers between several users. One technology that can help in providing these advantages is optical code division multiple access (CDMA). If low-complexity components are used, noise will be a significant problem and there is a need for error control to keep the error rates at an acceptable level. Error control for an optical CDMA network is one of the topics in this thesis. Our results show that there is a strong correlation between the error rates and the number of active users, which indicates the need for traffic control. Moreover, the performance is significantly improved by error correction and soft decoding.

In wireless networks, packet loss caused by transmission errors is a well-known problem. In particular for the transmission control protocol (TCP), the performance is severely degraded by losses that are not caused by congestion. In this thesis, end-to-end forward error correction (FEC) is considered as a solution. A further advantage of end-to-end FEC is that it can also improve TCP performance for large bandwidth-delay product paths, where TCP is also known to perform badly. The results show that the error control has to be designed with the requirements of the traffic control in mind.

The requirement on the network service is very different for a service like IP-telephony compared to web surfing; hence new traffic control methods are needed. For conversational applications it is important to have predictable performance during a session. For this purpose probe-based admission control can be used, but a problem with this approach is that it cannot isolate different applications with differing requirements on the loss rate. A solution is to combine the admission control with FEC to protect the ongoing sessions and provide consistent quality. Based on these ideas, a service architecture that can be deployed without upgrading the network is proposed and evaluated. The last part of this thesis also shows how this host based scheme could evolve into more complex schemes as network support is provided.

Place, publisher, year, edition, pages
Stockholm: KTH , 2005. , 36 p.
Series
Trita-S3-LCN, ISSN 1653-0837 ; 0511
Keyword [en]
Telecommunication
National Category
Telecommunications
Identifiers
URN: urn:nbn:se:kth:diva-468OAI: oai:DiVA.org:kth-468DiVA: diva2:13385
Public defence
2005-11-11, L1, KTH, Drottning Kristinas väg 30, Stockholm, 13:00
Opponent
Supervisors
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
List of papers
1. On Error-Correction Coding for CDMA PON
Open this publication in new window or tab >>On Error-Correction Coding for CDMA PON
2005 (English)In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 23, no 8, 2342-2351 p.Article in journal (Refereed) Published
Abstract [en]

Optical-code-division multiple access (OCDMA) has been investigated as a multiple-access technique for a long time, but so far, it has not reached any practical success. We investigate the performance of low-complexity OCDMA systems with a realistic model of noise and interference; the main limitation of the system is beat noise. To improve the performance, we consider forward-error correction (FEC) and soft decoding using standard error-correcting codes. The achievable error rates are evaluated using simulations and show significant improvement when FEC is used. The results also show that frequency-hopping systems perform better than temporally coded systems when beat noise is taken into account.

Keyword
Beat noise, Error-correction coding, Optical-code-division multiple access (OCDMA), Soft decoding
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8133 (URN)10.1109/JLT.2005.850776 (DOI)000231427100001 ()2-s2.0-24744461552 (Scopus ID)
Note
QC 20100924Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2017-12-14Bibliographically approved
2. On the Optimization of Local and End-to-End Forward Error Correction
Open this publication in new window or tab >>On the Optimization of Local and End-to-End Forward Error Correction
2005 (English)In: Proceedings of 11th European Wireless Conference, 2005, 652-658 p.Conference paper, Published paper (Other academic)
Abstract [en]

In this paper we investigate where best to use forward error correction if one or more mobile radio links is included on a path. On one hand, if the errors are handled locally where they appear, the knowledge of the channel conditions are better and no extra redundancy will have to traverse the other links. On the other hand, the requirements of the application are better known at the end nodes, hence the error correction can be better tuned to the needs of the application end-to-end. The first aspect investigated is the effect of a correlated error process, which is exemplified by a fading radio channel. The length of the error correcting code and the burst tolerance is essential for performance when correlation is taken into account, therefore packet level coding applied endto- end is efficient at high correlation whereas local bit error correction is more efficient at low correlation. TCP is used to exemplify the difficulties in estimating the parameters needed to implement effective coding both locally and end-to-end. Furthermore, simulation results show how the locally optimal parameters differ depending on the end-to-end path. Performance comparisons in several cases demonstrate that end-to-end forward error correction (FEC) can often be efficient to mitigate problems that are in principle local to a specific link.

National Category
Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-8134 (URN)2-s2.0-84946761172 (Scopus ID)
Conference
11th European Wireless Conference, Nicosia, Cyprus, April 10-13 2005
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
3. TCP with End-to-End Forward Error Correction
Open this publication in new window or tab >>TCP with End-to-End Forward Error Correction
2004 (English)In: Int. Zurich Seminar on Communications, 2004, 152-155 p.Conference paper, Published paper (Refereed)
Abstract [en]

Traditional TCP (end-to-end communication) implementations are tuned to work well over wired networks. A packet loss is occurred in a wired network mainly due to network congestion. On the other hand. in, a wireless link a large portion of packet losses are caused mainly due to propagation errors (causes bit errors), resultant from noise, interference, and various kinds of fading [1]. TCP has no. idea whether a packet loss is caused by congestion or bit error. Inclusion of Forward Error Correction (FEC) at TCP level recovers these bit errors.

Keyword
delays, forward error correction, telecommunication congestion control, transport protocols
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8135 (URN)10.1109/IZS.2004.1287411 (DOI)
Conference
4th International Conference on Electrical and Computer Engineering Dhaka, BANGLADESH, DEC 19-21, 2006
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
4. Adaptive End-to-End FEC for Improving TCP Performance over Wireless Links
Open this publication in new window or tab >>Adaptive End-to-End FEC for Improving TCP Performance over Wireless Links
2004 (English)In: 2004 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, 2004, 4023-4027 p.Conference paper, Published paper (Refereed)
Abstract [en]

TCP is a reliable transport protocol that has been tuned to perform well in networks where packet losses occur mostly because of congestion. However, wireless networks are different: TCP responds both to congestion-based and error-based losses by invoking a congestion control algorithm and reducing the sending rate, resulting in degraded end-to-end performance for wireless systems. We investigate a new end-to-end approach for improving TCP performance over lossy links by using adaptive, end-to-end forward error correction (FEC) for recovering losses and consequently avoiding the TCP back-off behaviour. Of course there is a clear trade-off between the capacity consumed by FEC and the gain achieved in the overall throughput. An adaptive algorithm is needed to calculate the optimum ratio of redundancy given the state of the connection. The sender uses feedback information from the receiver to dynamically tune the FEC parameters. Through simulations we evaluate the performance of TCP with end-to-end FEC in mixed wired and wireless networks. The simulation results show in different scenarios that the throughput can be significantly improved by adding end-to-end FEC to TCP. However, compared to other improved TCP variants such as Westwood+ the performance is not improved, hence a direct modification of TCP congestion control appears to be more efficient than adding end-to-end FEC.

Keyword
TCP, adaptive FEC, wireless, performance evaluation
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8136 (URN)10.1109/ICC.2004.1313306 (DOI)000223459600781 ()2-s2.0-4143106913 (Scopus ID)
Conference
IEEE International Conference on Communications (ICC 2004) Paris, FRANCE, JUN 20-24, 2004
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
5. Single-Service Quality Differentiation
Open this publication in new window or tab >>Single-Service Quality Differentiation
2004 (English)In: 2004 Twelfth IEEE International Workshop on Quality of Service, IWQoS 2004: Montreal, Ont.; 7 June 2004 through 9 June 2004, 2004, 265-272 p.Conference paper, Published paper (Refereed)
Abstract [en]

This paper proposes a scheme for quality of service differentiation for single-service networks that is based on the use of two separate forms of traffic control at the transport layer: Streams are controlled by means of probe-based admission control and elastic flows are controlled by TCP. The controls allow separation of traffic into two distinct service classes. The stream class is designed to provide a consistent quality for interactive audiovisual communication, as favored by human perception. It is responsive to load variations as an aggregate through blocking of sessions, while TCP is responsive on the flow level. Streams can be isolated against disturbances from probes and TCP flows by means of error-control coding. We show that the two traffic controls can coexist without starvation, and the proposed scheme might thus provide a first step towards differentiated services end-to-end.

Keyword
Approximation theory; Computer networks; Data communication systems; Data reduction; Decision making; Error analysis; Error correction; Multiplexing; Network protocols; Probability; Traffic control; Error control coding; Service-quality differentiation; Stream-data transfers; TCP (transmission control protocol)
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8137 (URN)10.1109/IWQOS.2004.1309392 (DOI)000222964800029 ()2-s2.0-4544385703 (Scopus ID)
Note
QC 20100826Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
6. Edge-based Differentiated Services
Open this publication in new window or tab >>Edge-based Differentiated Services
2005 (English)In: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 3552, 259-270 p.Article in journal (Refereed) Published
Abstract [en]

Network quality of service is traditionally thought to be provided by a combination of scheduling in the network nodes to enforce a capacity sharing policy and traffic controls to prevent congestion that could annihilate that policy. The work presented herein is instead based on an end-to-end argument: A capacity sharing policy is enforced by traffic controls in the hosts at the edges of the network, without any scheduling support in the network. Our proposal is to add a feed-forward control at the transport layer to provide a service that is better suited to conversational and streaming applications than the batch-oriented transfer mode provided by TCP. The paper presents the control and its evaluation: We compare the sharing of capacity between traffic classes and study the loss rate seen by admitted streams. The outcome is that the new control adds a distinctly different service to the service offered by TCP for the Internet.

Keyword
Congestion control (communication); Network protocols; Public policy; Telecommunication traffic; Differentiated services; End-to-end argument
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8138 (URN)000230383200021 ()2-s2.0-26444479632 (Scopus ID)
Note
QC 20100826. Ingår i Proc. of 13th International Workshop on Qualityof Service - IWQoS 2005.Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2017-12-14Bibliographically approved
7. Analytical model for a host-based service differentiation scheme
Open this publication in new window or tab >>Analytical model for a host-based service differentiation scheme
2005 (English)In: Performance Challenges for Efficient Next Generation Networks, Vols 6A-6C / [ed] Liang XJ, Xin ZH, Kuo GS, Iversen VB, 2005, 1455-1464 p.Conference paper, Published paper (Refereed)
Abstract [en]

Probe-based admission control has been proposed as a traffic control that can provide real-time traffic with quality of service and prevent congestion without any support from the network. We study methods to provide isolation and fairness between real-time traffic and elastic traffic by adding forward error correction (FEC) and by using appropriate probing procedures. An analytical model that can be used for evaluation of the scheme is presented and shows good correspondence with simulations.

Series
TELETRAFFIC SCIENCE AND ENGINEERING
Keyword
differentiated services, quality of service, traffic control, Internet, modeling
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8139 (URN)000232398501039 ()7-5635-1141-5 (ISBN)
Conference
19th International Teletraffic Congress (ITC 19) Beijing, PEOPLES R CHINA, AUG 29-SEP 02, 2005
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved
8. An Evolutionary Approach to Quality of Service
Open this publication in new window or tab >>An Evolutionary Approach to Quality of Service
2005 (English)Report (Other academic)
Publisher
30 p.
Series
Trita-S3-LCN, ISSN 1653-0837 ; 0510
National Category
Telecommunications
Identifiers
urn:nbn:se:kth:diva-8140 (URN)
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2013-09-09Bibliographically approved

Open Access in DiVA

fulltext(143 kB)730 downloads
File information
File name FULLTEXT01.pdfFile size 143 kBChecksum MD5
88255afe6e984044c96beec5723a2abc2a02907b48ed389c93a96c6b9111e762b0dbd108
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Lundqvist, Henrik
By organisation
School of Electrical Engineering (EES)
Telecommunications

Search outside of DiVA

GoogleGoogle Scholar
Total: 730 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

urn-nbn

Altmetric score

urn-nbn
Total: 773 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