Balakrishna Prabhu

Documents

Publications

	Weighted Scheduling of Time-Sensitive Coflows Olivier Brun , Rachid El-Azouzi , Quang-Trung Luu , Francesco De Pellegrini , Balakrishna Prabhu IEEE Transactions on Cloud Computing, 2024, 12 (2), pp.644-658. ⟨10.1109/TCC.2024.3384514⟩ Journal articles hal-04632943v1
	Markovian queues with Poisson control R. Núñez-Queija , J.A.C. Resing , Balakrishna Prabhu Indagationes Mathematicae, 2023, 34 (5), pp.990-1013. ⟨10.1016/j.indag.2023.03.002⟩ Journal articles hal-04064463v1
	A learning-based scheme for channel allocation to vehicular users in wireless networks Thi Thuy Nga Nguyen , Olivier Brun , Balakrishna Prabhu Performance Evaluation, 2023, 159, pp.102331. ⟨10.1016/j.peva.2023.102331⟩ Journal articles hal-03952289v1
	Using channel predictions for improved proportional-fair utility for vehicular users Thi Thuy Nga Nguyen , Olivier Brun , Balakrishna Prabhu Computer Networks, 2022, 208, ⟨10.1016/j.comnet.2022.108872⟩ Journal articles hal-02892099v2
	Queueing models with service speed adaptations at arrival instants of an external observer Rudesindo Núñez-Queija , Balakrishna Prabhu , Jacques Resing Queueing Systems, 2022, 100 (3-4), pp.233-235. ⟨10.1007/s11134-022-09790-7⟩ Journal articles hal-03871877v1
	Load-balancing for Multi-skilled Servers with Bernoulli Routing Fernando Miguelez , Josu Doncel , Balakrishna Prabhu Annals of Operations Research, 2022, 312 (2), pp.949-971. ⟨10.1007/s10479-022-04532-7⟩ Journal articles hal-03084240v1
	Macroscopic modelling and analysis of flows during rush-hour congestion Dieter Fiems , Balakrishna Prabhu Performance Evaluation, 2021, 149-150, pp.102218. ⟨10.1016/j.peva.2021.102218⟩ Journal articles hal-03384271v1
	Scheduling in a single-server with state-dependent service rates Urtzi Ayesta , Balakrishna Prabhu , Rhonda Righter Probability in the Engineering and Informational Sciences, 2020, 34 (4), pp.507 - 521. ⟨10.1017/S0269964819000160⟩ Journal articles hal-01783136v1
	Travel times, rational queueing and the macroscopic fundamental diagram of traffic flow Dieter Fiems , Balakrishna Prabhu , Koen de Turck Physica A: Statistical Mechanics and its Applications, 2019, 524, pp.412-421. ⟨10.1016/j.physa.2019.04.127⟩ Journal articles hal-02393141v1
	Performance of a fixed reward incentive scheme for two-hop DTNs with competing relays Thi Thu Hang Nguyen , Olivier Brun , Balakrishna Prabhu ACM Transactions on Modeling and Performance Evaluation of Computing Systems, 2019, 4 (2), ⟨10.1145/3325288⟩ Journal articles hal-01575320v2
	Sharing Within Limits: Partial Resource Pooling in Loss Systems Anvitha Nandigam , Suraj Jog , D. Manjunath , Jayakrishnan Nair , Balakrishna Prabhu IEEE/ACM Transactions on Networking, 2019, 27 (4), pp.1305-1318. ⟨10.1109/TNET.2019.2918164⟩ Journal articles hal-02388722v1
	Joint Minimization of Monitoring Cost and Delay in Overlay Networks: Optimal Policies with a Markovian Approach Sandrine Vaton , Olivier Brun , Maxime Mouchet , Pablo Belzarena , Isabel Amigo Journal of Network and Systems Management, 2019, 27 (1), pp.188-232. ⟨10.1007/s10922-018-9464-1⟩ Journal articles hal-01857738v1
	On the Design of a Reward-Based Incentive Mechanism for Delay Tolerant Networks Tatiana Seregina , Olivier Brun , Rachid Elazouzi , Balakrishna Prabhu IEEE Transactions on Mobile Computing, 2017, 16 (2), pp.453-465 Journal articles hal-01061348v2
	A Penalized Best-Response Algorithm for Non-Linear Single-Path Routing Problems Olivier Brun , Balakrishna Prabhu , Josselin Vallet Networks, 2017, Static and Dynamic Optimization Models for Network Routing Problems 69 (1), pp.52-66. ⟨10.1002/net.21720⟩ Journal articles hal-01461689v1
	Worst-case Analysis of Non-Cooperative Load Balancing Olivier Brun , Balakrishna Prabhu Annals of Operations Research, 2016, 239 (2), pp.471-495. ⟨10.1007/s10479-014-1747-7⟩ Journal articles hal-00747244v1
	A Resource-Sharing Game with Applications to Cloud-Computing Josu Doncel , Urtzi Ayesta , Olivier Brun , Balakrishna Prabhu Performance Evaluation, 2014, Special Issue: Performance 2014, 79, pp.287-305 Journal articles hal-01365943v1
	Is the Price of Anarchy the Right Measure for Load-Balancing Games? Josu Doncel , Urtzi Ayesta , Olivier Brun , Balakrishna Prabhu ACM Transactions on Internet Technology, 2014, 14 (2-3), pp.1 - 20. ⟨10.1145/2663498⟩ Journal articles hal-01462308v1
	Bandwidth sharing networks with multiscale traffic Mathieu Feuillet , Matthieu Jonckheere , Balakrishna Prabhu Stochastic Systems, 2014, 4 (2), pp. 449-478 Journal articles hal-01229329v1
	Load Balancing in Processor Sharing Systems Eitan Altman , Urtzi Ayesta , Balakrishna Prabhu Telecommunication Systems, 2011, 47 (1-2), pp.35-48 Journal articles hal-00286455v2

	Data Summarization for Federated Learning Julianna Devillers , Olivier Brun , Balakrishna Prabhu Proceedings of the 6th International Conference on Machine Learning for Networking (MLN'2023), Nov 2023, Paris, France Conference papers hal-04295982v1
	DCoflow: Deadline-Aware Scheduling Algorithm for Coflows in Datacenter Networks Quang-Trung Luu , Olivier Brun , Rachid El-Azouzi , Francesco de Pellegrini , Balakrishna Prabhu IFIP Networking Conference, Jun 2022, Catania, Italy. ⟨10.23919/IFIPNetworking55013.2022.9829789⟩ Conference papers hal-03657370v1
	Partial resource pooling in loss systems with two players Anvitha Nandigam , Suraj Jog , D Manjunath , Jayakrishnan Nair , Balakrishna Prabhu 23ème congrès annuel de la Société Française de Recherche Opérationnelle et d'Aide à la Décision, INSA Lyon, Feb 2022, Villeurbanne - Lyon, France Conference papers hal-03596216v1
	TREMA: A traffic-aware energy efficient MAC protocol to adapt the LoRaWAN capacity Laurent Chasserat , Nicola Accettura , Balakrishna Prabhu , Pascal Berthou 2021 International Conference on Computer Communications and Networks (ICCCN), Jul 2021, Athens, Greece. ⟨10.1109/ICCCN52240.2021.9522147⟩ Conference papers hal-02998586v3
	Performance Evaluation of Some Adaptive Task Allocation Algorithms for Fog Networks Ioanna Stypsanelli , Olivier Brun , Balakrishna Prabhu IEEE 5th International Conference on Fog and Edge Computing (ICFEC 2021), May 2021, Melbourne, Australia. ⟨10.1109/ICFEC51620.2021.00020⟩ Conference papers hal-02972802v1
	Reducing Service Migrations in Fog Infrastructures by Optimizing Node Location Ioanna Stypsanelli , Samir Medjiah , Balakrishna Prabhu 2020 Fifth International Conference on Fog and Mobile Edge Computing (FMEC), Apr 2020, Paris, France. pp.13-19, ⟨10.1109/FMEC49853.2020.9144775⟩ Conference papers hal-03006775v1
	Learning resource allocation algorithms for cellular networks Thi Thuy Nga Nguyen , Olivier Brun , Balakrishna Prabhu Machine Learning for Networking: Third International Conference (MLN 2020), Nov 2020, Paris, France. ⟨10.1007/978-3-030-70866-5_12⟩ Conference papers hal-03753556v1
	A Markovian approach for improving end-to-end data rates in the Internet Marine Ségneré-Yter , Olivier Brun , Balakrishna Prabhu International Conference on NETwork Games, Control and Optimisation (Netgcoop 2020), Mar 2020, Cargèse, France Conference papers hal-02901139v1
	Macroscopic modelling and analysis of rush-hour congestion Dieter Fiems , Balakrishna Prabhu VALUETOOLS '20: 13th EAI International Conference on Performance Evaluation Methodologies and Tools, 2020, Tsukuba, Japan. pp.11-18, ⟨10.1145/3388831.3388849⟩ Conference papers hal-03007545v1
	Scalable Monitoring Heuristics for Improving Network Latency Maxime Mouchet , Martin Randall , Marine Ségneré , Isabel Amigo , Pablo Belzarena NOMS 2020 : IEEE/IFIP Network Operations and Management Symposium, Apr 2020, Budapest, Hungary. ⟨10.1109/NOMS47738.2020.9110341⟩ Conference papers hal-02413636v1
	Joint downlink power control and channel allocation based on a partial view of future channel conditions Thi Thuy Nga Nguyen , Olivier Brun , Balakrishna Prabhu The 15th Workshop on Resource Allocation, Cooperation and Competition in Wireless Networks (RAWNET), Jun 2020, Volos, Greece Conference papers hal-03006880v1
	Partial Server Pooling in Redundancy Systems Akshay Mete , D. Manjunath , Jayakrishnan Nair , Balakrishna Prabhu 2019 31st International Teletraffic Congress (ITC 31), Aug 2019, Budapest, Hungary. pp.106-114, ⟨10.1109/ITC31.2019.00024⟩ Conference papers hal-02390451v1
	Capacity Planning of Fog Computing Infrastructures under Probabilistic Delay Guarantees Ioanna Stypsanelli , Olivier Brun , Samir Medjiah , Balakrishna Prabhu IEEE International Conference on Fog Computing (ICFC 2019), Jun 2019, Prague, Czech Republic Conference papers hal-02065179v1
	An algorithm for improved proportional-fair utility for vehicular users Thi Thuy Nga Nguyen , Olivier Brun , Balakrishna Prabhu The 25th International Conference on Analytical & Stochastic Modelling Techniques & Applications ASMTA-2019, Oct 2019, Moscow, Russia Conference papers hal-02376712v1
	Scheduling users in drive-thru Internet: a multi-armed bandit approach Thi Thuy Nga Nguyen , Urtzi Ayesta , Balakrishna Prabhu WiOpt 2019, International Federation for Information Processing (IFIP), Jun 2019, Avignon, France. ⟨10.23919/WiOPT47501.2019.9144139⟩ Conference papers hal-02112621v1
	Mean-field limit of the fixed-reward incentive mechanism in Delay Tolerant Networks Thi Thu Hang Nguyen , Olivier Brun , Balakrishna Prabhu 16th Symposium on Modeling and Optimization in Mobile, Ad Hoc and Wireless Networks (WiOpt 2018), May 2018, Shanghai, China. ⟨10.23919/WIOPT.2018.8362810⟩ Conference papers hal-02062180v1
	Optimisation conjointe de la métrologie active et du routage : une approche markovienne Maxime Mouchet , Sandrine Vaton , Olivier Brun , Pablo Belzarena , Isabel Amigo Rencontres Francophones sur la Conception de Protocoles, l’Évaluation de Performance et l’Expérimentation des Réseaux de Communication, May 2018, Roscoff, France Conference papers hal-01785870v1
	Low Power Radiolocation through Long Range Wide Area Networks: a performance study Nicola Accettura , Samir Medjiah , Balakrishna Prabhu , Thierry Monteil 2017 IEEE 13th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), Oct 2017, Rome, Italy. pp.1-8, ⟨10.1109/WiMOB.2017.8115799⟩ Conference papers hal-02063812v1
	Simulating scalable Long Range Wide Area Networks for very low power monitoring applications Nicola Accettura , Balakrishna Prabhu , Thierry Monteil The 22nd International Congress on Modelling and Simulation (MODSIM2017), Dec 2017, Hobart, Australia. pp.797-803 Conference papers hal-02063841v1
	Performance of a fixed reward incentive scheme for two-hop DTNs with competing relays Hang Thi Thu Nguyen , Olivier Brun , Balakrishna Prabhu The 11th Workshop on the Economics of Networks, Systems and Computation (NetEcon 2016), Jun 2016, Juan-les-Pins, France Conference papers hal-01365939v1
	Asymptotics of Insensitive Load Balancing and Blocking Phases Matthieu Jonckheere , Balakrishna Prabhu ACM SIGMETRICS / IFIP Performance 2016, Jun 2016, Antibes, France Conference papers hal-01299605v1
	A Game-theoretic Algorithm for Non-Linear Single-Path Routing Problems Josselin Vallet , Olivier Brun , Balakrishna Prabhu 7th International Network Optimisation Conference (INOC 2015), May 2015, Varsovie, Poland Conference papers hal-01245236v2
	A Fluid model based Heuristic for Optimal Speed-scaling in Bandwidth-sharing Networks Olivier Brun , Henda Ben Cheikh , Balakrishna Prabhu IFIP WG 7.3 Performance 2015 - The 33rd International Symposium on Computer Performance, Modeling, Measurements and Evaluation 2015, IFIP, Oct 2015, Sydney, Australia Conference papers hal-01094506v3
	Information dissemination processes in directed social networks Konstantin Avrachenkov , Koen de Turck , Dieter Fiems , Balakrishna Prabhu International Workshop on Modeling, Analysis and Management of Social Networks and their Applications (SOCNET 2014), Mar 2014, Bamberg, Germany. pp.35-43 Conference papers hal-00876873v1
	Modeling rewards and incentive mechanisms for Delay Tolerant Networks Olivier Brun , Rachid El-Azouzi , Balakrishna Prabhu , Tatiana Seregina 12th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks (WiOpt 2014), May 2014, Hammamet, Tunisia. pp.233 - 240, ⟨10.1109/WIOPT.2014.6850304⟩ Conference papers hal-01462314v1
	Predicting Response Times of Applications in Virtualized Environments Henda Ben Cheikh , Josu Doncel , Olivier Brun , Balakrishna Prabhu IEEE 3rd Symposium on Network Cloud Computing and Applications (NCCA 2014), Feb 2014, Rome, Italy. pp.83-90, ⟨10.1109/NCCA.2014.21⟩ Conference papers hal-02062289v1
	On the convergence of the best-response algorithm in routing games Olivier Brun , Balakrishna Prabhu , Tatiana Seregina 7th International Conference on Performance Evaluation Methodologies and Tools (ValueTools), Dec 2013, Turin, Italy. 27p Conference papers hal-00862298v1
	On the Efficiency of Non-Cooperative Load Balancing Josu Doncel , Balakrishna Prabhu , Olivier Brun , Urtzi Ayesta IFIP Networking 2013, May 2013, Brooklyn, United States. 15p Conference papers hal-00768339v1
	Analysis of an M/G/1 queue with customer impatience and adaptive arrival process Onno Boxma , Balakrishna Prabhu NetGCOOP 2011 : International conference on NETwork Games, COntrol and OPtimization, Telecom SudParis et Université Paris Descartes, Oct 2011, Paris, France Conference papers hal-00644866v1
	Spatio-temporal control for Dynamic Routing Games Manjesh Kumar Hanawal , Eitan Altman , Rachid El-Azouzi , Balakrishna Prabhu 2nd International ICST Conference, GAMENETS 2011, Apr 2011, Shanghai, China Conference papers hal-01299682v1

	Actes du 11ème Atelier en Évaluation de Performances Urtzi Ayesta , Balakrishna Prabhu , Ina Maria Maaike Verloop Urtzi AYESTA; Balakrishna J. PRABHU; Ina Maria VERLOOP. 11ème Atelier en Évaluation de Performances (2016), Mar 2016, Toulouse, France. , 2016 Proceedings hal-01292528v1

	Special volume on selected papers from the second ECQT conference (ECQT 2016), Toulouse, France Urtzi Ayesta , Balakrishna Prabhu Ayesta, Urtzi; Prabhu, Balakrishna. , 119, 53 p., 2018, Performance Evaluation, ISSN: 0166-5316. ⟨10.1016/j.peva.2017.12.001⟩ Books hal-03120286v1
	EUROPEAN CONFERENCE ON QUEUEING THEORY 2016 Urtzi Ayesta , Marko Boon , Balakrishna Prabhu , Rhonda Righter , Ina Maria Maaike Verloop , 72p, 2016 Books hal-01368218v1

	A Mixed Strategy for a Competitive Game in Delay Tolerant Networks Thi Thu Hang Nguyen , Olivier Brun , Balakrishna Prabhu Computer Performance Engineering - 15th European Workshop, EPEW 2018, Paris, France, October 29-30, 2018, Proceedings, pp.190-204, 2018, ⟨10.1007/978-3-030-02227-3_13⟩ Book sections hal-02062162v1
	Analysis of a RED Queue: A Singular Perturbation Approach Eitan Altman , Konstantin Avrachenkov , Balakrishna Prabhu Demetres D. Kouvatsos. Traffic and Performance Engineering for Heterogeneous Networks, 1, River Publishers, pp.371-397, 2009, 9788792329165. ⟨10.1201/9781003339878-22⟩ Book sections hal-03831912v1

	Partial Server Pooling in Delay Systems V. Hari Rohit , Akshay Mete , D. Manjunath , Jayakrishnan Nair , Balakrishna Prabhu 2024 Preprints, Working Papers, ... hal-04443590v1
	Ubiquitous multi-gateway LoRa networks: models and performance evaluation Nicola Accettura , Balakrishna Prabhu 2024 Preprints, Working Papers, ... hal-02914373v2
	Prediction-based Coflow Scheduling Olivier Brun , Balakrishna Prabhu , Oumayma Haddaji 2023 Preprints, Working Papers, ... hal-04231370v1
	A Threshold Type Policy of a DTN Node Under Fixed Reward Incentive Mechanisms Tatiana Seregina , Olivier Brun , Balakrishna Prabhu 2018 Preprints, Working Papers, ... hal-01708410v1
	Responding to traffic surges: Stochastic networks under time-space-priority scalings Matthieu Feuillet , Matthieu Jonckheere , Balakrishna Prabhu 2011 Preprints, Working Papers, ... hal-00559494v1
	Price of Anarchy in Non-Cooperative Load Balancing Urtzi Ayesta , Olivier Brun , Balakrishna Prabhu 2009 Preprints, Working Papers, ... hal-00416123v1

	Deliverable D1 - Technical Report NF-PERSEUS 2023 Charbel Abdel Nour , Cédric Adjih , Karine Amis , Xavier Begaud , Matthieu Crussière CEA - Commissariat à l'énergie atomique et aux énergies alternatives. 2024, pp.1-86 Reports cea-04564147v1
	On the Equilibria of Resource-Sharing Games Josu Doncel , Urtzi Ayesta , Olivier Brun , Balakrishna Prabhu 2013 Reports hal-00910195v1
	Control of Buffer and Energy of a Wireless Device: Closed and Open Loop Approaches V. S. Borkar , A. A. Kherani , Balakrishna Prabhu [Research Report] RR-5414, INRIA. 2006, pp.24 Reports inria-00070592v1
	Uplink dynamic discrete power control in cellular networks Eitan Altman , Konstantin Avrachenkov , Gregory Miller , Balakrishna Prabhu [Research Report] RR-5818, INRIA. 2006, pp.31 Reports inria-00070207v2
	Performance Analysis and Stochastic Stability of Congestion Control Protocols Eitan Altman , Konstantin Avrachenkov , Arzad A. Kherani , Balakrishna Prabhu [Research Report] RR-5262, Inria Sophia Antipolis; INRIA. 2004, pp.56 Reports inria-00070736v1
	Fairness in MIMD Congestion Control Algorithms Eitan Altman , Konstantin Avrachenkov , Balakrishna Prabhu [Research Report] RR-5312, INRIA. 2004, pp.29 Reports inria-00070688v1

	Markov chains and decision processes for congestion avoidance and power control Balakrishna Prabhu Networking and Internet Architecture [cs.NI]. Université Nice Sophia Antipolis, 2005. English. ⟨NNT : ⟩ Theses tel-00328111v1

Balakrishna Prabhu

Publications

Weighted Scheduling of Time-Sensitive Coflows

Markovian queues with Poisson control

A learning-based scheme for channel allocation to vehicular users in wireless networks

Using channel predictions for improved proportional-fair utility for vehicular users

Queueing models with service speed adaptations at arrival instants of an external observer

Load-balancing for Multi-skilled Servers with Bernoulli Routing

Macroscopic modelling and analysis of flows during rush-hour congestion

Scheduling in a single-server with state-dependent service rates

Travel times, rational queueing and the macroscopic fundamental diagram of traffic flow

Performance of a fixed reward incentive scheme for two-hop DTNs with competing relays

Sharing Within Limits: Partial Resource Pooling in Loss Systems

Joint Minimization of Monitoring Cost and Delay in Overlay Networks: Optimal Policies with a Markovian Approach

On the Design of a Reward-Based Incentive Mechanism for Delay Tolerant Networks

A Penalized Best-Response Algorithm for Non-Linear Single-Path Routing Problems

Worst-case Analysis of Non-Cooperative Load Balancing

A Resource-Sharing Game with Applications to Cloud-Computing

Is the Price of Anarchy the Right Measure for Load-Balancing Games?

Bandwidth sharing networks with multiscale traffic

Load Balancing in Processor Sharing Systems

Data Summarization for Federated Learning

DCoflow: Deadline-Aware Scheduling Algorithm for Coflows in Datacenter Networks

Partial resource pooling in loss systems with two players

TREMA: A traffic-aware energy efficient MAC protocol to adapt the LoRaWAN capacity

Performance Evaluation of Some Adaptive Task Allocation Algorithms for Fog Networks

Reducing Service Migrations in Fog Infrastructures by Optimizing Node Location

Learning resource allocation algorithms for cellular networks

A Markovian approach for improving end-to-end data rates in the Internet

Macroscopic modelling and analysis of rush-hour congestion

Scalable Monitoring Heuristics for Improving Network Latency

Joint downlink power control and channel allocation based on a partial view of future channel conditions

Partial Server Pooling in Redundancy Systems

Capacity Planning of Fog Computing Infrastructures under Probabilistic Delay Guarantees

An algorithm for improved proportional-fair utility for vehicular users

Scheduling users in drive-thru Internet: a multi-armed bandit approach

Mean-field limit of the fixed-reward incentive mechanism in Delay Tolerant Networks

Optimisation conjointe de la métrologie active et du routage : une approche markovienne

Low Power Radiolocation through Long Range Wide Area Networks: a performance study

Simulating scalable Long Range Wide Area Networks for very low power monitoring applications

Performance of a fixed reward incentive scheme for two-hop DTNs with competing relays

Asymptotics of Insensitive Load Balancing and Blocking Phases

A Game-theoretic Algorithm for Non-Linear Single-Path Routing Problems

A Fluid model based Heuristic for Optimal Speed-scaling in Bandwidth-sharing Networks

Information dissemination processes in directed social networks

Modeling rewards and incentive mechanisms for Delay Tolerant Networks

Predicting Response Times of Applications in Virtualized Environments

On the convergence of the best-response algorithm in routing games

On the Efficiency of Non-Cooperative Load Balancing

Analysis of an M/G/1 queue with customer impatience and adaptive arrival process

Spatio-temporal control for Dynamic Routing Games

Actes du 11ème Atelier en Évaluation de Performances

Special volume on selected papers from the second ECQT conference (ECQT 2016), Toulouse, France

EUROPEAN CONFERENCE ON QUEUEING THEORY 2016

A Mixed Strategy for a Competitive Game in Delay Tolerant Networks

Analysis of a RED Queue: A Singular Perturbation Approach

Partial Server Pooling in Delay Systems

Ubiquitous multi-gateway LoRa networks: models and performance evaluation

Prediction-based Coflow Scheduling

A Threshold Type Policy of a DTN Node Under Fixed Reward Incentive Mechanisms

Responding to traffic surges: Stochastic networks under time-space-priority scalings

Price of Anarchy in Non-Cooperative Load Balancing

Deliverable D1 - Technical Report NF-PERSEUS 2023

On the Equilibria of Resource-Sharing Games

Control of Buffer and Energy of a Wireless Device: Closed and Open Loop Approaches

Uplink dynamic discrete power control in cellular networks

Performance Analysis and Stochastic Stability of Congestion Control Protocols

Fairness in MIMD Congestion Control Algorithms

Markov chains and decision processes for congestion avoidance and power control