• Vol 7, No 4 (2016)
  • Electrical, Electronics, and Computer Engineering

Enhanced Low Latency Queuing Algorithm for Real Time Applications in Wireless Networks

P. Rukmani, R. Ganesan

Corresponding email: rukmani.p@vit.ac.in

Published at : 29 Apr 2016
IJtech : IJtech Vol 7, No 4 (2016)
DOI : https://doi.org/10.14716/ijtech.v7i4.1805

Cite this article as:

Rukmani, P., & Ganesan, R. 2016. Enhanced Low Latency Queuing Algorithm for Real Time Applications in Wireless Networks. International Journal of Technology. Volume 7(4), pp.663-672

P. Rukmani School of Computing Science and Engineering, VIT University, Chennai Campus, Chennai 600127, India
R. Ganesan School of Computing Science and Engineering, VIT University, Chennai Campus, Chennai 600127, India
Email to Corresponding Author


In recent times, the demand for the real time audio and video applications in wireless networks is very high due to widespread use of latest wireless communication technologies. Many of these applications require different Quality of Service (QoS) in terms of delay and throughput in the resource constrained wireless networks. In order to handle the resources effectively and to increase the QoS, proper packet scheduling algorithms need to be developed. Low-latency Queuing (LLQ) is a packet scheduling algorithm which combines Strict Priority Queuing (SPQ) to Class-Based Weighted Fair Queuing (CB-WFQ). LLQ places delay sensitive applications such as voice and video in the SPQ and treat them preferentially over other traffic by allowing the application to be processed and sent first from the SPQ. In this paper, an Enhanced LLQ (ELLQ) is proposed. An additional SPQ is introduced for scheduling the video applications separately along with the dedicated SPQ for voice applications. The performance of the proposed algorithm is compared with other existing algorithms through simulations using the OPNET modeler. Simulation and Statistical results show that the proposed algorithm has given 1.5 times performance improvement in terms of throughput and delay than the existing algorithms for the real time audio and video applications.

Low Latency Queuing (LLQ), Quality of Service (QoS), Real time applications, Scheduling algorithms, Wireless networks


Adarshpal, S.S., Vasil, Y.H., 2013. The Practical OPNET User Guide for Computer Network Simulation. CRC Press. New York, USA

Annadurai, C., 2011. Review of Packet Scheduling Algorithms in Mobile Ad Hoc Networks. International Journal of Computer Applications, Volume 15(1), pp. 7–10

Brunonas, D., Tomas, A., Aurelijus, B., 2006. Analysis of QoS Assurance using Weighted Fair Queuing (WFQ) Scheduling Discipline with Low Latency Queue (LLQ). In: 28th International Conference Information Technology Interfaces, Croatia, June 19-22, IEEE

Checkpoint, 2013. Introduction to QoS. Available online at: https://sc1.checkpoint.com/documents/R76/CP_R76_QoS_AdminGuide/index.html, Accessed on September, 2015

Chuck, S., 2001. Supporting Differentiated Service Classes: Queue Scheduling Disciplines. White Paper, Juniper Networks

Eric, H.W., Ming-I, H., Hsu-Te, L., 2006. Low Latency and Efficient Packet Scheduling for Streaming Applications. Journal of Computer Communications, Volume 29(9), pp.1413–1421

Farzad, A., Sahar, K., Bahram, S.B., 2008. A New Scheduling Algorithm Based on Traffic Classification using Imprecise Computation. International Journal of Computer, Control, Quantum and Information Engineering, Volume 2(9), pp.78–82

Fatpipe Networks, 1996. Bandwidth Management: FatPipe's Multi-line QoS Avoids Network Congestion. Available online at: http://www.fatpipeinc.com/technology/bandwidth-management.php, Accessed on September, 2015

Hyunchul, J., Ki Jin, A., Hwangjun, S., 2011. Urgency-based Packet Scheduling and Routing Algorithms for Video Transmission over MANETS. In: IET International Communication Conference on Wireless Mobile and Computing, Shanghai, November 14-16, IET

Jesus, A., Perez, V.H.Z., Christian, C., 2006. A Network and Data Link Layer QoS Model to Improve Traffic Performance. Emerging Directions in Embedded and Ubiquitous Computing, Lecture Notes in Computer Science, Springer Berlin Heidelberg, pp.224–233

Juniper Networks, 1999. QoS Design. Available online at: https://www.juniper.net/techpubs/en_US/junos-space11.4/junos-space-QoS-Design-sub-index.html, Accessed on September, 2015

Low Latency Queuing, 2008. Low Latency Queueing. Available online at: http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/fsllq26.html, Accessed on September, 2015

Palo Alto Networks, 2015. Quality of Service. Available online at: https://paloaltonetworks.com/documentation/61/pan-os/pan-os/quality-of-service.html, Accessed on September, 2015

Quality of Service Design Overview, 2014. Chapter: Quality of Service Design Overview. Available online at: http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/QoSIntro.html, Accessed on September, 2015

Rukmani, P., Ganesan, R., 2013. Scheduling Algorithm for Real Time Applications in Mobile Ad Hoc Network with OPNET Modeler. Journal of Procedia Engineering, Volume 64, pp. 94–103

Shaimaa, B., Fatma, B., Gamal, D., 2011. QoS Adaptation in Real Time Systems based on CBWFQ. In: 28th National Radio Science Conference (NRSC), Cairo, April 26-28, IEEE, pp.1–8

Tetsuji, H., 2010. Analysis of Multiclass Feedback Queues and its Application to a Packet Scheduling Problem. Journal of Industrial and Management Optimization, Volume 6(3), pp. 541–568

Wendell, O., Michael, J.C., 2004. Cisco DQOS Exam Certification Guide. Cisco Press, USA

Youssef, D., Noufissa, M., 2008. Priority Assignment for Multimedia Packets Scheduling in MANET. In: International Conference on Signal Image Technology and Internet Based Systems, Bali, November 30-December 8, IEEE