Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 20) Show all publications
Abbas, M. T., Eklund, J., Grinnemo, K.-J. & Brunström, A. (2019). Impact of Tunable Parameters in NB-IoT Stack onthe Energy Consumption. In: Proceedings of Fifteenth Swedish National Computer Networking Workshop (SNCNW): . Paper presented at 15th Swedish National Computer Networking Workshop (SNCNW 2019). Luleå, June 4-5, 2019..
Open this publication in new window or tab >>Impact of Tunable Parameters in NB-IoT Stack onthe Energy Consumption
2019 (English)In: Proceedings of Fifteenth Swedish National Computer Networking Workshop (SNCNW), 2019Conference paper, Published paper (Refereed)
Abstract [en]

This paper studies the impact of tunable parametersin the NB-IoT stack on the energy consumption of a user equipment(UE), e.g., a wireless sensor. NB-IoT is designed to enablemassive machine-type communications for UE while providing abattery lifetime of up to 10 years. To save battery power, most oftime the UE is in dormant state and unreachable. Still, duringthe CONNECTED and IDLE state, correct tuning of criticalparameters, like Discontinuous reception (DRX), and extendedDiscontinuous reception (eDRX), respectively, are essential to savebattery power. Moreover, the DRX and eDRX actions relate tovarious parameters which are needed to be tuned in order toachieve a required UE battery lifetime. The objective of thispaper is to observe the influence of an appropriate tuning ofthese parameters to reduce the risk of an early battery drainage

Keywords
NB-IoT, energy consumption, DRX, eDRX.
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-72440 (URN)
Conference
15th Swedish National Computer Networking Workshop (SNCNW 2019). Luleå, June 4-5, 2019.
Projects
HITS; 4707
Funder
Knowledge Foundation
Available from: 2019-06-12 Created: 2019-06-12 Last updated: 2019-07-03Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunström, A. (2018). Using multiple paths in SCTP to reduce latency for signaling traffic. Computer Communications, 129, 184-196
Open this publication in new window or tab >>Using multiple paths in SCTP to reduce latency for signaling traffic
2018 (English)In: Computer Communications, ISSN 0140-3664, E-ISSN 1873-703X, Vol. 129, p. 184-196Article in journal (Refereed) Published
Abstract [en]

The increase in traffic volumes as well as the heterogeneity in network infrastructure in the upcoming 5G cellular networks will lead to a dramatic increase in volumes of control traffic, i.e., signaling traffic, in the networks. Moreover, the increasing number of low-power devices with an on-off behavior to save energy will generate extra control traffic. These increased traffic volumes for signaling traffic, often generated as bursts of messages, will challenge the signaling application timing requirements on transmission. One of the major transport protocols deployed for signaling traffic in cellular networks is the Stream Control Transmission Protocol (SCTP), with support for multiple paths as well as for independent data flows. This paper evaluates transmission over several paths in SCTP to keep the latency low despite increasing traffic volumes. We explore different transmission strategies and find that concurrent multipath transfer over several paths will significantly reduce latency for transmission over network paths with the same or similar delay. Still, over heterogeneous paths, careful, continuous sender scheduling is crucial to keep latency low. To this end, we design and evaluate a sender scheduler that considers path characteristics as well as queuing status and data flows of different priority to make scheduling decisions. Our results indicate that by careful dynamic sender scheduling, concurrent multipath transfer could lead to reduced latency for signaling traffic irrespective of path or traffic characteristics.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Computer Engineering Robotics
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-70258 (URN)10.1016/j.comcom.2018.07.016 (DOI)000446282200015 ()
Available from: 2018-11-22 Created: 2018-11-22 Last updated: 2019-01-31Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunstrom, A. (2016). Efficient Scheduling to Reduce Latency for Signaling Traffic using CMT-SCTP. In: 27th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), September 4-7, Valencia, Spain: . Paper presented at 27th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC) September 4-7, Valencia, Spain. IEEE Communications Society
Open this publication in new window or tab >>Efficient Scheduling to Reduce Latency for Signaling Traffic using CMT-SCTP
2016 (English)In: 27th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), September 4-7, Valencia, Spain, IEEE Communications Society, 2016Conference paper, Published paper (Refereed)
Abstract [en]

To mitigate delay spikes during transmission of bursty signaling traffic, concurrent multipath transmission (CMT) over several paths in parallel could be an option. Still, unordered delivery is a well known problem when concurrently transmitting data over asymmetric network paths, leading to extra delay due to Head-of-Line Blocking (HoLB). The Stream Control Transmission Protocol (SCTP), designed as a carrier for signaling traffic over IP, is currently being extended with support for CMT (CMT-SCTP). To reduce the impact of HoLB, SCTP has support for transmission of separate data flows, called SCTP streams. In this paper, we address sender scheduling to optimize latency for signaling traffic using CMT-SCTP. We present dynamic stream-aware (DS) scheduling, which utilizes the SCTP stream concept, and continuously considers the current network status as well as the data load to make scheduling decisions. We implement a DS scheduler and compare it against some existing schedulers. Our investigation suggests that DS scheduling could significantly reduce latency compared to dynamic path scheduling that does not consider streams. Moreover, we show that naive round-robin scheduling may provide low latency over symmetric network paths, but may transmit data on non-beneficial asymmetric network paths leading to increased latency. Finally, our results show that a static stream based approach, found beneficial for bulk traffic, is not appropriate for bursty signaling traffic. 

Place, publisher, year, edition, pages
IEEE Communications Society, 2016
Keywords
CMT-SCTP, real-time traffic, latency; scheduling, signaling, QoS
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-42634 (URN)000391598800361 ()
Conference
27th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC) September 4-7, Valencia, Spain
Projects
HITS
Funder
Knowledge Foundation
Available from: 2016-06-07 Created: 2016-06-07 Last updated: 2018-06-04Bibliographically approved
Eklund, J. (2016). Latency Reduction for Soft Real-Time Traffic using SCTP Multihoming. (Doctoral dissertation). Karlstad: Karlstad University Press
Open this publication in new window or tab >>Latency Reduction for Soft Real-Time Traffic using SCTP Multihoming
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

More and more so-called soft real-time traffic is being sent over IP-based networks. The bursty, data-limited traffic pattern as well as the latency requirements from this traffic present challenges to the traditional communication techniques, designed for bulk traffic without considering latency.

To meet the requirements from soft real-time traffic, in particular from telephony signaling, the Stream Control Transmission Protocol (SCTP) was designed. Its support for connectivity to multiple networks, i.e., multihoming, provides robustness and opens up for concurrent multipath transfer (CMT) over multiple paths. Since SCTP is a general transport protocol, it also enables for handover of media sessions between heterogeneous networks. Migrating an ongoing session to a new network, as well as CMT with minimal latency, requires tuning of several protocol parameters and mechanisms.

This thesis addresses latency reduction for soft real-time traffic using SCTP multihoming from three perspectives. The first focus is on latency for signaling traffic in case of path failure, where a path switch, a failover, occurs. We regard quick failure detection as well as rapid startup on the failover target path. The results indicate that by careful parameter tuning, the failover time may be significantly reduced. The second focus in the thesis is on latency for signaling traffic using CMT. To this end, we address sender-side scheduling. We evaluate some existing schedulers, and design a dynamic stream-aware scheduler. The results indicate that the dynamic stream-aware scheduler may provide significantly improved latency in unbalanced networks. Finally, we target multihomed SCTP to provide for handover of a media session between heterogeneous wireless networks in a mobile scenario. We implement a handover scheme and our investigation shows that SCTP could provide for seamless handover of a media session at walking speed.

Abstract [en]

So-called soft real-time traffic may be sent over IP-based networks. The bursty, data-limited traffic pattern and the latency requirements from this traffic present a challenge to traditional communication techniques. The Stream Control Transmission Protocol (SCTP), with support for multihoming, was designed to better meet the requirements from soft-real time traffic. Multihoming provides for robustness and for concurrent multipath transfer (CMT) as well as for handover of sessions between heterogeneous networks. Still, to meet the timeliness requirements, tuning of protocol parameters and mechanisms is crucial.

This thesis addresses latency reduction for soft real-time traffic using SCTP multihoming. The first focus is on signaling traffic in case of path failure, where a path switch, a failover, occurs. We show that careful parameter tuning may reduce the failover time significantly. The second focus is on signaling traffic using CMT. We address sender-side scheduling and show that dynamic stream-aware scheduling may reduce latency when data is transmitted over asymmetric network  paths. The third focus is multihomed SCTP for handover between heterogeneous networks, where we show that SCTP could provide for seamless handover of a media session at walking speed.

Place, publisher, year, edition, pages
Karlstad: Karlstad University Press, 2016. p. 34
Series
Karlstad University Studies, ISSN 1403-8099 ; 2016:14
Keywords
transport protocol, SCTP, multihoming, latency, performance evaluation, failover, concurrent multipath transfer, scheduling, mobility, handover
National Category
Computer Sciences
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-40713 (URN)978-91-7063-693-6 (ISBN)
Public defence
2016-06-17, 21A342, Karlstad, 09:30 (English)
Opponent
Supervisors
Note

Paper 3 (Efficient Scheduling to Reduce Latency...) ingick i avhandlingen som manuskript med samma namn.

Available from: 2016-05-18 Created: 2016-02-25 Last updated: 2018-01-10Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunström, A. (2016). Stream-aware Scheduling to Improve Latency for Signaling Traffic using CMT-SCTP. In: : . Paper presented at Swedish National Computer Networking Workshop (SNCNW 16) Sundsvall 1-2 juni.
Open this publication in new window or tab >>Stream-aware Scheduling to Improve Latency for Signaling Traffic using CMT-SCTP
2016 (English)Conference paper, Published paper (Refereed)
Abstract [en]

To mitigate delay spikes during transmission ofbursty signaling traffic, concurrent multipath transmission(CMT) over several paths in parallel could be an option. Still,unordered delivery is a well known problem when transmittingover asymmetric network paths, leading to extra delay due toHead-of-Line Blocking (HoLB). The Stream Control TransmissionProtocol (SCTP) is designed as a carrier for signaling trafficover IP to reduce the impact of HoLB. SCTP has support fortransmission of separate flows, called SCTP streams. SCTP iscurrently being extended with support for CMT (CMT-SCTP). Inthis paper, we address sender scheduling to optimize latency forsignaling traffic over CMT-SCTP. We present dynamic streamaware(DS) scheduling, which utilizes the SCTP stream concept,and continuously considers the current network status as well asthe data load to make scheduling decisions. We implement a DSScheduler and compare it against a dynamic path (DP) schedulerthat does not consider streams. Our investigation shows that DSscheduling could significantly reduce latency compared to a DPscheduler.

National Category
Communication Systems
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-43499 (URN)
Conference
Swedish National Computer Networking Workshop (SNCNW 16) Sundsvall 1-2 juni
Projects
HITS
Available from: 2016-06-22 Created: 2016-06-22 Last updated: 2018-06-21Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunström, A. (2015). On the Impact of Data Scheduling to Reduce Latency for Telephony Signaling Traffic using CMT-SCTP. In: The 11th Swedish National Computer Networking Workshop (SNCNW), Karlstad, Sweden, May 28-29, 2015.: . Paper presented at The 11th Swedish National Computer Networking Workshop (SNCNW), May 28-29, 2015, Karlstad, Sweden.
Open this publication in new window or tab >>On the Impact of Data Scheduling to Reduce Latency for Telephony Signaling Traffic using CMT-SCTP
2015 (English)In: The 11th Swedish National Computer Networking Workshop (SNCNW), Karlstad, Sweden, May 28-29, 2015., 2015Conference paper, Oral presentation only (Other academic)
Abstract [en]

SCTP is a transport protocol targeted for telephony signaling traffic. Although SCTP from its inception supported multihoming, it has until now not supported concurrent mul- tipath transfer. However, this is about to change: Currently a standard for concurrent multipath transfer is underway. Since it is unclear whether concurrent multipath transfer could reduce transmission latency, this paper evaluates two algorithms for scheduling signaling traffic for transmission. We find that the mechanisms may provide good performance and to some extent enables for service differentiation. Still, the results indicate that unpredictable traffic require dynamic scheduling.

Keywords
sctp, transport protocol, scheduling, latency
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-36058 (URN)
Conference
The 11th Swedish National Computer Networking Workshop (SNCNW), May 28-29, 2015, Karlstad, Sweden
Projects
HITS
Funder
Knowledge Foundation
Available from: 2015-05-21 Created: 2015-05-21 Last updated: 2018-06-04Bibliographically approved
Söderman, P., Eklund, J., Grinnemo, K.-J., Hidell, M. & Brunstrom, A. (2013). Handover in the Wild: The Feasibility of Vertical Handover in Commodity Smartphones. In: Proceedings of the IEEE International Conference on Communications (ICC): . Paper presented at IEEE International Conference on Communications (ICC) 2013, Budapest, Hungary, June 9-13, 2013 (pp. 6401-6406). IEEE
Open this publication in new window or tab >>Handover in the Wild: The Feasibility of Vertical Handover in Commodity Smartphones
Show others...
2013 (English)In: Proceedings of the IEEE International Conference on Communications (ICC), IEEE, 2013, p. 6401-6406Conference paper, Published paper (Refereed)
Abstract [en]

Today commodity mobile devices are frequently equipped with two wireless access technologies,WiFi and 3G/4G. To enable continuous connectivity it is vital that these terminals provide for vertical handover between different technologies. Particularly, they should provide a vertical handover that complies with the timeliness requirements of soft real-time applications. Considering aspects such as cost and ease-of-deployment, ap- plication neutrality, and, not least, the emergence of transport protocols that support multi-homing such as mobile SCTP and multi-path TCP, we think it would be beneficial to handle vertical handover in the transport layer of the mobile terminal. This paper demonstrates through several real-world experiments, the feasibility of using a lightweight vertical handover scheme in smart mobile terminals for live video streaming. The vertical handover criteria is based on the received signal strength. Our experiments suggest that the scheme indeed provides for seamless vertical handover at walking speed – our target scenario. However, the experiments also suggest that the scheme gives significant reductions in handover time, as compared to mobile SCTP without improvements, at higher speeds.

Place, publisher, year, edition, pages
IEEE, 2013
Series
IEEE International Conference on Communications, ISSN 1550-3607
Keywords
sctp, dar, vertical handover
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-33907 (URN)10.1109/ICC.2013.6655635 (DOI)000349673807056 ()978-1-4673-3122-7 (ISBN)
Conference
IEEE International Conference on Communications (ICC) 2013, Budapest, Hungary, June 9-13, 2013
Funder
VINNOVA
Available from: 2014-10-01 Created: 2014-10-01 Last updated: 2018-06-04Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunstrom, A. (2012). Implications of using a Large Initial Congestion Window to Improve mSCTP Handover Delay. In: Josef Noll, University of Oslo & Movation, Norway, Alessandro Bazzi, CNR - IEIIT, Italy (Ed.), MOBILITY 2012 : The Second International Conference on Mobile Services, Resources, and Users. Paper presented at The Second International Conference on Mobile Services, Resources, and Users (MOBILITY, Venice, Italy from October 21, 2012 to October 26, 2012 (pp. 116-121). IARIA
Open this publication in new window or tab >>Implications of using a Large Initial Congestion Window to Improve mSCTP Handover Delay
2012 (English)In: MOBILITY 2012 : The Second International Conference on Mobile Services, Resources, and Users / [ed] Josef Noll, University of Oslo & Movation, Norway, Alessandro Bazzi, CNR - IEIIT, Italy, IARIA , 2012, , p. 6p. 116-121Conference paper, Published paper (Refereed)
Abstract [en]

The currently rather heterogeneous wireless landscape makes handover between different network technologies, so-called vertical handover, a key to a continued success for wireless Internet access. Recently, an extension to the Stream Control Transmission Protocol (SCTP) – the Dynamic Address Reconfiguration (DAR) extension – was standardized by IETF. This extension enables the use of SCTP for vertical handover. Still, the way vertical handover works in SCTP with DAR makes it less suitable for real-time traffic. Particularly, it takes a significant amount of time for the traffic to ramp up to full speed on the handover target path. In this paper, we study the implications of an increased initial congestion window for real-time traffic on the handover target path when competing traffic is present. The results clearly show that an increased initial congestion window could significantly reduce the transfer delay for real-time traffic, provided the fair share of the available capacity on the handover target path is sufficiently higher than the send rate required by the real-time flow. Additionally, we notice that this performance gain comes without penalizing the competing traffic.

Place, publisher, year, edition, pages
IARIA, 2012. p. 6
Keywords
SCTP, dynamic address reconfiguration, video, mobility, handover, congestion control, slow start
National Category
Telecommunications
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-26493 (URN)978-1-61208-229-5 (ISBN)
Conference
The Second International Conference on Mobile Services, Resources, and Users (MOBILITY, Venice, Italy from October 21, 2012 to October 26, 2012
Projects
SCTP SmartSwitch - Smart Session Management for Multihomed SCTP
Funder
Vinnova
Available from: 2013-02-25 Created: 2013-02-25 Last updated: 2018-06-04Bibliographically approved
Eklund, J., Grinnemo, K.-J. & Brunstrom, A. (2012). On the Use of an Increased Initial Congestion Window to Improve mSCTP Handover Performance. In: Leonard Barolli, Tomoya Enokido, Fatos Xhafa, Makoto Takizawa (Ed.), WAINA 2012: 26th International Conference on Advanced Information Networking and Applications Workshops. Paper presented at WAINA 2012 - 26th IEEE International Conference on Advanced Information Networking and Applications Workshops, Fukuoka, Japan, March 26-29 (pp. 1101-1106). IEEE Press
Open this publication in new window or tab >>On the Use of an Increased Initial Congestion Window to Improve mSCTP Handover Performance
2012 (English)In: WAINA 2012: 26th International Conference on Advanced Information Networking and Applications Workshops / [ed] Leonard Barolli, Tomoya Enokido, Fatos Xhafa, Makoto Takizawa, IEEE Press, 2012, p. 1101-1106Conference paper, Published paper (Refereed)
Abstract [en]

With the wireless landscape being ratherheterogeneous, handover between different networktechnologies, so-called vertical handover, becomes keyto a continued success for wireless Internet access.Recently, an extension to the Stream Control Trans-mission Protocol (SCTP) – the Dynamic Address Re-configuration (DAR) extension – was standardized bythe IETF. This extension enables the use of SCTPfor vertical handover. Still, the way vertical handoverworks in SCTP with DAR makes it less suitable for real-time traffic. Particularly, it takes a significant amountof time for the traffic to ramp up to full speed on thehandover target path. In this paper, we study the ex-tent to which an increased initial congestion window onthe handover target path decreases the transfer delayspikes in real-time video traffic experienced during avertical handover. The impact on both standard andhigh-definition video traffic is considered. The resultsof our study suggest that an increased initial congestionwindow does indeed significantly decrease the spikes inthe video traffic. However, the results also indicate thatit does not resolve the problem altogether.

Place, publisher, year, edition, pages
IEEE Press, 2012
Keywords
SCTP; Dynamic Address Reconfiguration; Video; Mobility; Multihoming; Congestion Control; Handover
National Category
Computer Systems
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-13350 (URN)10.1109/WAINA.2012.111 (DOI)978-0-7695-4652-0 (ISBN)
Conference
WAINA 2012 - 26th IEEE International Conference on Advanced Information Networking and Applications Workshops, Fukuoka, Japan, March 26-29
Projects
SCTP Smartswitch
Note

Ingår i projekt

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

x

Available from: 2012-05-22 Created: 2012-05-22 Last updated: 2018-06-04Bibliographically approved
Eklund, J., Brunström, A., Grinnemo, K.-J., Cheimonidis, G. & Ismailov, Y. (2011). Delay Penalty during SCTP Handover. Paper presented at 7th Swedish National Computer Networking Workshop SNCNW 2011, Linköping, June 13-14, 2011.
Open this publication in new window or tab >>Delay Penalty during SCTP Handover
Show others...
2011 (English)Conference paper, Published paper (Refereed)
Abstract [en]

The rapidly growing interest in untethered Internet connections such as WLAN and 3G/4G mobile connections,calls for intelligent session management, not least in terms of handovers. As part of an effort to develop a SCTP-based session management framework, we are studying ways of improving the SCTP handover delay forreal-time traffic by optimizing the startup delay on the handover-target path. We have developed a theoretical model that predicts the transfer times of SCTP messages during the startup on a new path. This paper validates our model. It shows that the model can be used to predict message transfer times in variable bitrate flows. The paper further employs our model to study the startup delay penalty during handover for the spectrum of network conditions considered relevant for real-time traffic over mobile connections.

National Category
Computer Sciences
Research subject
Computer Science
Identifiers
urn:nbn:se:kau:diva-10786 (URN)
Conference
7th Swedish National Computer Networking Workshop SNCNW 2011, Linköping, June 13-14, 2011
Available from: 2012-02-08 Created: 2012-02-08 Last updated: 2018-06-04Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-6723-881X

Search in DiVA

Show all publications