RT info:eu-repo/semantics/article T1 multiclass aQM on a tCP/IP router: a control theory approach A1 El Fezazi, Nabil A1 El Haoussi, Fatima A1 Tissir, El Houssaine A1 bender, Fernando Augusto A1 Álvarez Álvarez, María Teresa K1 AQM, congested traffic conditions, control theory, heterogeneous traffic, time-varying delay, input saturation K1 331005 AB Active queue management (AQM) is a well-known technique to improve routing performance under congested traffic conditions. It is often deployed to regulate queue sizes, thus aiming for constant transmission delay. This work addresses AQM using an approach based on control theory ideas. Compared with previous results in the literature, the novelty is the consideration of heterogeneous traffic, ie, multiclass traffic. Thus, each traffic class may have different discarding policies, queue sizes, and bandwidth share. This feature brings the proposal nearer to real network management demands than previous approaches in the literature. The proposed technique assumes that each class already has a simple controller, designed a priori, and focuses on designing a static state-feedback controller for the multiclass system, where the design is based on using LMIs for the calculations. For this, optimization problems with LMI constraints are proposed to compute the state-feedback gains that ensure stability for a large set of admissible initial conditions. These conditions ensure not only closed-loop stability but also some level of performance. As far as we know, this is the first control theory based approach for the AQM problem on TCP/IP routers that allows a multiclass AQM while also considering time-varying delays and input saturation. This is an important step to frame AQM in a more formal, yet realistic context, enabling it to address important service level agreement (SLA) directives. The proposal is tested on a simulated system at the end of this paper, showing the feasibility and performance of the approach in the presence of multiclass traffic. PB Wiley SN 1099-1239 YR 2019 FD 2019 LK https://uvadoc.uva.es/handle/10324/64328 UL https://uvadoc.uva.es/handle/10324/64328 LA spa NO International Journal of Robust and Adaptative Control, Volume29, Issue6 1 April 2019 Pages 1719-1733 NO Producción Científica DS UVaDOC RD 22-nov-2024