Aisha

POWER CONSUMPTION INTELECOMMUNICATION

NETWORKS:OVERVIEW AND REDUCTIONSTRATEGIES

January 4, 2014

GUIDED BY: PRESENTED BY:Mr.Lenin Joseph Aisha.SAsst. Professor Roll No.02Dept. of ECE M.Tech,ECESBCEW SBCEW 1 / 29

CONTENTS

• Introduction

• Why do we care about energy efficiency?

• Network Architectures

• Access Network Architecture

• Analysis of Optical and DSL technologies

• Customer Premises Equipment

• Core network architecture

• Quantification of power consumption

• Optimization of power consumption

• Conclusion

2 / 29

PREFACE

OBJECTIVES

• To give an idea about energy efficiency in communicationnetworks.

• To examine different network’s power consumption.

• To discuss power quantification and optimization methods invarious networks.

APPROACH

• Discussion on various network architectures and its powerconsumption.

• Effects of power consumption on energy efficiency.

• Quantification and optimization of power consumption.

• Conclusion

3 / 29

INTRODUCTION

• Every emerging technology is mainly evaluated on its carbonfootprint.

• Information and Communication Technology (ICT) isaccountable for 2-4 % of worldwide carbon emissions.

• One sixth of these emissions is contributed bytelecommunication networks.

Figure 1: Electricity consumption per year by various fields

4 / 29

INTRODUCTION(CONTD...)

• ICT is being regarded as a solution with the potential toeliminate about 15 % of the global carbon footprint.

• Sleep mode, component optimization and power managementare the already suggested power saving strategies.

• Different network architectures, its design parameters definingpower consumption, methods for quantification and thereduction techniques are discussed here.

5 / 29

WHY DO WE CARE ABOUT ENERGY EFFICIENCY?

• From a simple transistor to environment, thermal energy isincreasing.

• ICT alone is responsible of a percentage which vary from 2 −4% of the world power consumption.

• Pressure to reduce network power consumption while stillgrowing network capacity and functionality.

• Scalability• Power density in racks of communication equipments is

reaching practical limits.• Makes cost-efficient scaling of telecommunication networks

difficult.

6 / 29

NETWORK ARCHITECTURES

• ACCESS NETWORKS• CORE NETWORKS

• Access Networks can be again classified as:• FIXED LINE ACCESS NETWORKS• WIRELESS ACCESS NETWORKS

Figure 2: Network Overview

7 / 29

ACCESS NETWORK ARCHITECTURE

Fixed line access networks

• Users are connected through physical wires.

• 3 main types of technologies are in use :-

• DSL(Digital Subscriber Line)-Asymmetric DSL , Very high bitrate DSL

• Coax cable technology-uses Data Over Cable ServiceInterface Specification Standard.

• Optical technology-point- point , active star or PassiveOptical Network (PON).

• Cable access networks are constructed with an opticalbackhaul-HFC

• Optical access networks can be terminated with VDSLnode-FTTB ,FTTC , FTTx

8 / 29

ANALYSIS OF OPTICAL AND DSL TECHNOLOGIES

• Traffic in access network is bursty and highly variable.

• Power consumption per subscriber is considered as a metric.

ADSL

• Downstream speeds: 8 Mbps(ADSL) to 24 Mbps(ADSL2+)

• Upstream speed : 1 Mbps

• Maximum range : 1.5 km to 5.5 km

• Range allows large user aggregation-hence power consumptionis negligible

VDSL

• Uses an extended frequency spectrum compared to ADSL.

• Aggregation is closer to the user- so significant powerconsumption.

9 / 29

ANALYSIS OF OPTICAL AND DSLTECHNOLOGIES(contd...)

Optical fiber technology

• Allows both high bit rates( upto 10Gbps) and range(10-20km).

• P2P connections are used in backhaul network to aggregatelarge traffic.

• In active star and PON ,bit rate capacity is distributed overlarge number of users.

10 / 29

WIRELESS ACCESS NETWORKS

• Different technologies provides different access bit rates to theuser.

• 3 main emerging wireless technologies are:-

• WiMAX( Worldwide Interoperability for MicrowaveAccess)-IEEE802.16 std.

• HSPA (High- Speed Packet Access)-successor of UMTS

• LTE (Long Term Evolution)-4G technology

• The factor under consideration for determining power in awireless access network is the area covered by the basestations.

• The covered area is related to the input power of the basestation antenna and the bit rate.

11 / 29

CUSTOMER PREMISES EQUIPMENT

• At the customer premises, access networks will be connectedto the customer premises equipment.

• For fixed line networks it will be a home gateway.

• For wireless networks, it can be any equipment-like mobilephone,home gateway, wireless network interface card in acomputer etc.

• Hence wireless technologies are generally called as mobilestations.

12 / 29

CORE NETWORK ARCHITECTURE

• Current core networks are mix of several layers like IP-over-ATM - over- SDH.

Figure 3: Core network architecture

13 / 29

QUANTIFICATION OF POWER CONSUMPTION

FIXED LINE ACCESS NETWORKS

• Each subscriber has a dedicated connection.

• ADSL equipment consumes 1-2W/sub and VDSL consumes3-5W/sub.

• Optical network consumes 10-20W/port which can be furtherreduced if GPON is used.

• OLT-Optical Line Terminal-using for connection consumes0.2-0.8W/sub.

• VDSL DSLAM with 16 connections use only 0.01-0.05W/sub.

• Power Usage Effectiveness (PUE) - typically a factor of 2

14 / 29

QUANTIFICATION OF POWER CONSUMPTION(contd...)

WIRELESS ACCESS NETWORKS

• Highest power consumer is the base station.

• Power per subscriber is dependant on the subscriber density inthe area covered by the base station.

• For comparison a bit rate / active user is taken as 3Mbps forall technologies.

• WiMAX - Lowest- 2.9kW/BS - Range of 340 m• LTE - Highest - 3.7kW/BS - Range of 470 m• HSPA - Intermediate - 3.7kW/BS - Range of 240 m

• If subscriber density is considered as 300users/sq.km in urbanand sub urban areas:

• LTE-18W/Subs• WiMAX-27W/Subs• HSPA-68W/Subs

15 / 29

QUANTIFICATION OF POWERCONSUMPTION(contd...)

CUSTOMER PREMISES EQUIPMENT

• The home gateway consumes about 5-10 W for fixed linetechnologies.

• Home gateways for optical networks also have larger energyconsumption compared to its DSL counterparts.

• In wireless networks, the power consumption of mobile stationsis much lower since these are designed for mobile applications.

CORE NETWORKS

• 90% of power consumption is concentrated in the nodes.

• WDM links via optical amplifiers make up only 10% of powerconsumption.

16 / 29


Figure 4: Generalized core network power consumption distribution

• Layer 1 and 2-provides framing, physical connection to aspecific network(ATM. SONET , Ethernet or SDH) etc.

• Currently the power consumption in core networks is lesscompared to access networks.

17 / 29


Figure 5: Properties of different access network technologies

18 / 29


Figure 6: Power consumption/subscriber of different network technologies

19 / 29

POWER CONSUMPTION OPTIMIZATION

• SWITCHING OFF COMPONENTS

• REDUCING LOAD

• OPTIMIZING POWER CONSUMPTION OF THEREMAINING COMPONENTS

20 / 29

POWER CONSUMPTION OPTIMIZATION (contd...)

SWITCHING OFF COMPONENTS

• Switch off elements when demand is lower.

• Dynamic topology optimization -used in core networks

• Dynamic Bandwidth Allocation -used in fixed line accessnetworks.

• Hybrid hierarchical base station deployment -used inwireless access networks.

• Optimization of power in home gateway is important.

• These are individual devices that needs to be activated onlywhen the user is active.

21 / 29


REDUCING LOAD

• Adaptive link rate (ALR) -Used in access networks.

• Link rates are adapted on the basis of factors such as meanpacket delay and packet loss based on a handshakemechanism.

• An ethernet link with ALR can operate at a lower data ratefor over 80 percent of the time, yielding significant energysavings with only a very small increase in packet delay

• The algorithms for adaptive link rate use large packet bufferswhich require hardware that needs to be powered.

22 / 29


REDUCING LOAD

• A non bypass scenario: all the traffics in a node will beprocessed by the IP router

• Optical bypass - used in core networks.

• As IP routers consumes the most power,optical bypassing is apromising option to decrease power consumption.

• Optical bypasses uses the same infrastructure as the originalopaque network hence no additional capacity is added to thenetwork.

23 / 29


Table 1: Reduction of total PC for different traffic loads using opticalbypass - standby PC: 0.81678 MW

Network load(E) PC with 0 bypass with 10 bypasses reduction

140 1.2751 1.18696 6.91

280 1.7457 1.57327 9.88

420 2.2793 2.00099 12.21

560 2.7719 2.46233 13.17

24 / 29


OPTIMIZING THE POWER CONSUMPTION OFREMAINING COMPONENTS

• Increasing the ranges of base stations using MIMO - inwireless access networks.

• Optical packet switching and Optical burst switching -Used in core networks.

• A hybrid approach in which optical switches using electronicbuffering is a more feasible low-power approach for the future.

• For continent - sized core networks , increasing themaximum optical path length can reduce powerconsumption.

25 / 29

CONCLUSION

• The number of internet users is fast increasing hence thepower consumption also.

• Saving power in telecommunication networks is becoming animportant challenge.

• For reducing power; switching off components , reducing theloads on the networks and optimizing the power consumptionof the network elements can be adopted.

• In fixed line access networks power consumption optimizationis focused on the technology shift towards full opticalnetworks.

• In wireless access networks many optimizations can still beimplemented.

• In core networks the power consumption is relatively low.

26 / 29

REFERENCES

• [1].Vereecken, W.; Van Heddeghem, W.; Deruyck, M.; Puype,B.; Lannoo, B.; Joseph, W.; Colle, D.; Martens, L.;Demeester, P., ”Power consumption in telecommunicationnetworks: overview and reduction strategies,”Communications Magazine, IEEE , vol.49, no.6, pp.62-69,June 2011

• [2].S. Aleksic, Analysis of Power Consumption in FutureHigh-Capacity Network Nodes, IEEE/OSA J. Opt.Commun.and Net., vol. 1, no. 3, Aug. 2009, pp. 24558.

• [3].K. Christensen and B. Nordman, Reducing the EnergyConsumption of Networked Devices, IEEE 802.3 tutorial,2005.

• [4]. M. Gupta and S. Singh, Greening of the Internet,SIGCOMM03: Proc. 2003 Conf. Apps.,Technologies,Architectures, and Protocols for ComputerCommun.,New York, NY, USA: ACM, 2003, pp. 1926.

27 / 29

QUERIES?????

28 / 29

THANK YOU!!

29 / 29