Energy Efficient Ethernet: High-impact Strategies - What You Need to Know: Definitions, Adoptions, Impact, Benefits, Maturity, Vendors

Kevin Roebuck

Description

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Energy Efficient Ethernet is a set of enhancements to the twisted-pair and backplane Ethernet family of computer networking standards that will allow for less power consumption during periods of low data activity. The intention was to reduce power consumption by 50% or more, while retaining full compatibility with existing equipment. The Institute of Electrical and Electronics Engineers (IEEE), through the IEEE 802.3az task force developed the standard. The IEEE ratified the final standard in September 2010. Some companies introduced technology to reduce the power required for Ethernet before the standard was ratified, using the name Green Ethernet.

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In easy to read chapters, with extensive references and links to get you to know all there is to know about Energy Efficient Ethernet right away. A quick look inside: Energy Efficient Ethernet, IEEE 802, 100BaseVG, 3G MIMO, Audio Video Bridging, Comparison of 802.15.4 radio modules, Daintree Networks (company), IEEE 802.1D, IEEE 802.1X, IEEE 802.2, IEEE 802.3, IEEE 802.6, IEEE 802.7, IEEE 802.1, IEEE 802.10, IEEE 802.15, IEEE 802.15.4, IEEE 802.15.4a, IEEE 802.16, IEEE 802.18, IEEE 802.19, IEEE 802.1ad, IEEE 802.1AE, IEEE 802.1ag, IEEE 802.1ah-2008, IEEE 802.1aq, IEEE P802.1p, IEEE 802.1Q, Stream Reservation Protocol, Provider Backbone Bridge Traffic Engineering, 802.1s, 802.1w, IEEE 802.20, IEEE 802.21, IEEE 802.22, IEEE 802.3ba, IEEE 802.8, IEEE 802.9, List of deployed WiMAX networks, Local Multipoint Distribution Service, Many antennas, Microwave Bypass (company), MIMO, MiWi, Multiple Registration Protocol, Physical Layer Convergence Protocol, Priority-based flow control, PU2RC, Resilient Packet Ring, Spatial multiplexing, Supplicant (computer), Token bus network, Token ring, WiMAX, Zero-forcing precoding, ZigBee ...and Much, Much More!

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• Publié par: Emereo Publishing
• Date de parution: 24 octobre 2012
• Nombre de lectures: 0
• EAN13: 9781743380123
• Langue: English
• Poids de l'ouvrage: 9 Mo

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Contents

Articles Energy Efficient Ethernet IEEE 802 100BaseVG 3G MIMO Audio Video Bridging Comparison of 802.15.4 radio modules Daintree Networks (company) IEEE 802.1D IEEE 802.1X IEEE 802.2 IEEE 802.3 IEEE 802.6 IEEE 802.7 IEEE 802.1 IEEE 802.10 IEEE 802.15 IEEE 802.15.4 IEEE 802.15.4a IEEE 802.16 IEEE 802.18 IEEE 802.19 IEEE 802.1ad IEEE 802.1AE IEEE 802.1ag IEEE 802.1ah-2008 IEEE 802.1aq IEEE P802.1p IEEE 802.1Q Stream Reservation Protocol Provider Backbone Bridge Traffic Engineering 802.1s 802.1w IEEE 802.20 IEEE 802.21

1 3 5 6 10 19 29 31 31 37 39 41 41 41 45 46 49 54 56 60 60 61 65 66 69 70 87 88 91 91 93 103 112 115

IEEE 802.22 IEEE 802.3ba IEEE 802.8 IEEE 802.9 List of deployed WiMAX networks Local Multipoint Distribution Service Many antennas Microwave Bypass (company) MIMO MiWi Multiple Registration Protocol Physical Layer Convergence Protocol Priority-based flow control PU2RC Resilient Packet Ring Spatial multiplexing Supplicant (computer) Token bus network Token ring WiMAX Zero-forcing precoding ZigBee

References Article Sources and Contributors Image Sources, Licenses and Contributors

Article Licenses License

117 120 121 121 121 134 135 136 137 144 146 148 148 149 156 157 159 160 161 166 179 181

190 193

195

Energy Efficient Ethernet

Energy Efficient Ethernet

Energy Efficient Ethernetis a set of enhancements to the twisted-pair and backplane Ethernet family of computer networking standards that will allow for less power consumption during periods of low data activity. The intention was to reduce power consumption by 50% or more, while [1] retaining full compatibility with existing equipment. The Institute of Electrical and Electronics Engineers (IEEE), through theIEEE 802.3az task force developed the standard. The IEEE ratified the final standard in [2] September 2010. Some companies introduced technology to reduce the power required for Ethernet before the standard was ratified, using the nameGreen Ethernet.

Logo of the study group and standard task force

Potential savings In 2005, all the network interface controllers in the United States (in computers, switches, and routers) used an [3] estimated 5.3 terawatt-hours of electricity. According to a researcher at the Lawrence Berkeley Laboratory, Energy [4] Efficient Ethernet could save an estimated US$450 million a year in energy costs in the U.S. Most of the savings [4] from homes ($200 million), and offices ($170 million), and the remaining $80 million from data centers. The first study group had its call for interest in November 2006, and the official standards task force was authorized in May [5] 2007.

Concepts The power reduction is accomplished in a few ways. In 100 Mbit/s, 1 gigabit and 10 Gbit/s speed data links energy is used to keep the physical layer transmitters on all the time. If they could be put into "sleep" mode when no data is [4] being sent that energy could be saved. By sending a low-power-idle (LPI) indication signal for a specified time the transmit chips in the system can be turned off. LPI is sent periodically to refresh the sleep mode. When there is data to transmit a normal idle signal is sent to wake the transmit system up before data is due to be sent. The data link is considered to be always operational, as the receive signal ciruit remains active even when the transmit path is in sleep mode. In addition, a new lower power mode was added to Ethernet over twisted pair, which reduces power supplies [6] required for each interface.

Green Ethernet Green Ethernet was a marketing term for Ethernet power-saving technology in 2007 and 2008.

Compared to IEEE Standard 802.3az [7] Some energy efficient switch integrated circuits were developed before the IEEE 802.3az standard was finalized. [8]

Green Ethernet technology was a superset of the 802.3az standard. In addition to the link load power savings of Energy Efficient Ethernet, Green Ethernet works in one of two ways. First, it detects link status, allowing each port on the switch to power down into a standby or‘sleep’mode when a connected device, such as a computer, is not active. Second, it detects cable length and adjusts the power accordingly. Previous standard switches provide enough [9] power to send a signal up to 100 meters (330 ft). However, this is often unnecessary, especially in the home where 5 to 10 meters (16 to 33 ft) of cabling are typical between rooms.

1

Energy Efficient Ethernet

Green Ethernet also encompasses the use of more efficient circuitry in Ethernet chips, and the use of "off-load [8] engines" on Ethernet interface cards intended for network servers.

Routers [10] In April 2008, the term was used for switches, and in July 2008, introduced into wireless routers. A Wireless LAN scheduler using Wireless N Gigabit routers automatically determines when Wi-Fi radio signals are turned on and off to further reduce energy consumption.

Power savings Green Ethernet was first employed on home products. However, low port counts mean that significant cost savings are not going to be made using this technology only in the home. Turning off existing devices when they are idle is [11] likely to provide a more immediate saving. Projected power savings of up to 45 - 80 percent were estimated using [12] [13] Green Ethernet switches, translating into a longer product life due to reduced heat dissipation.

References

[1] Sean Michael Kerner (July 17, 2009). "Energy Efficient Ethernet hits standards milestone—InternetNews:The Blog—Sean Michael Kerner" (http://blog.internetnews.com/skerner/2009/07/energy-efficient-ethernet-hits.html).Internetnews blog. . Retrieved July 5, 2011. [2] "IEEE ratifies new 8023az standard to reduce network energy footprint" (http:/ /www.lightwaveonline.com/education/news/ IEEE-ratifies-new-8023az-standard-to-reduce-network-energy-footprint--104392129. html).Lightwaveonline.com. October 5, 2010. . Retrieved July 5, 2011. [3] Prachi Patel-Predd (May 2008). "Energy-Efficient Ethernet" (http:/ /spectrum.ieee.org/computing/networks/energyefficient-ethernet). IEEE SpectrumEnergy-Efficient Ethernet: Ethernet connections waste lots of watts. It need not be so(Spectrum.ieee.org). . Retrieved July 5, 2011. [4] Rick Merritt (May 8, 2008). "Energy-efficient Ethernet standard gains traction" (http:/ /www.eetimes.com/electronics-news/4076984/ Energy-efficient-Ethernet-standard-gains-traction/).EE Times. . Retrieved July 5, 2011. [5] "IEEE 802.3 Energy Efficient Ethernet Study Group" (http:/ /www.ieee802.org/3/eee_study/index.html). September 21, 2007. . Retrieved July 5, 2011. [6] "IEEE 802.3az: Energy Efficient Ethernet in the Works" (http:/ /www.goodcleantech.com/2008/09/ieee_8023az_energy_efficient_e.php). GoodCleanTech blog. Ziff Davis. September 4, 2008. . Retrieved July 5, 2011. [7] "Top OEMs 'Go Green' With Broadcom's 65nm SMB Switch Family" (http:/ /www.broadcom.com/press/release.php?id=s387906) (Press release). Broadcom Corporation. June 3, 2009. . Retrieved July 5, 2011. "'The reduced power consumption offered by these single-chip switch solutions results in an energy saving device with reduced operating costs.' said Jacky Chang, Senior Director at D-Link. 'As part of our D-Link Green™initiative, we aim to give consumers ecologically friendly choices. By combining Broadcom's switch solutions with our green technology, we have been able to develop our second generation of Green Ethernet switches that provide competitive solutions with enhanced power saving benefits for all of our customers, from home users to enterprise.'" [8] Nicholas Ilyadis (April 1, 2010). "Broadcom Energy Efficiency Initiatives" (http:/ /www.calit2.uci.edu/uploads/Media/Text/ Ilyadis_BRCM_EEN_Update_UCI Workshop April 1 2010. pdf) (PDF). Broadcom. . Retrieved July 5, 2011. [9] "Ethernet 100BaseTX and 10BaseT Cables: Guidelines and specifications" (http:/ /www.cisco.com/en/US/products/hw/routers/ps133/ products_tech_note09186a00801f5d9e.shtml#limits).Cisco 10000 Series Routers. Cisco Systems. August 1, 2006. Specifications and Connection Limits for 100-Mbps Transmission. . Retrieved August 29, 2010. [10] "D-Link First Company to Offer Green Wi-Fi Home Networking" (http:/ /www.dlinkgreen.com/press.asp?pressrelease_id=3).News release(D-Link). July 28, 2008. . Retrieved July 5, 2011. [11] Tom Higins (April 23, 2008). "How Much Can D-Link's "Green Ethernet" Switch Save You?" (http:/ /www.smallnetbuilder.com/lanwan/ lanwan-features/30407-how-much-can-d-links-qgreen-ethernetq-switch-save-you).Small Net Builder blog. . Retrieved July 5, 2011. [12] "D-Link First Company to Offer 'Green Ethernet™/' Technology for Network Connectivity, Embrace Energy-Saving Initiatives" (http:/ www.dlinkgreen.com/press.asp?pressrelease_id=6). D-Link. October 24, 2007. . Retrieved July 5, 2011. "For example, when connected and subsequently powered down, the DGS-2208 multi-port desktop switch can realize up to 80 percent savings in power usage*, and the other D-Link 'Green Ethernet' switches can save up to 45 percent in power usage." [13] Brad Kenney (April 11, 2008). "Green Ethernet" (http:/ /www.industryweek.com/articles/green_ethernet_16103.aspx).IndustryWeek. . Retrieved July 5, 2011.

2

Energy Efficient Ethernet

External links a IEEE P802.3az Energy Efficient Ethernet Task Force (http://www.ieee802.org/3/az/index.html) "Green Ethernet" (http://web.archive.org/web/20090618035001/http://greenethernet.com/). Archived from the original (http://www.greenethernet.com) on June 18, 2009. Retrieved July 5, 2011. Blog for Energy Efficient Ethernet techniques and news analyses, circa 2009.

IEEE 802

IEEE 802refers to a family of IEEE standards dealing with local area networks and metropolitan area networks. More specifically, the IEEE 802 standards are restricted to networks carrying variable-size packets. (By contrast, in cell relay networks data is transmitted in short, uniformly sized units called cells. Isochronous networks, where data is transmitted as a steady stream of octets, or groups of octets, at regular time intervals, are also out of the scope of [1] this standard.) The number 802 was simply the next free number IEEE could assign, though“802”is sometimes associated with the date the first meeting was held—February 1980.

The services and protocols specified in IEEE 802 map to the lower two layers (Data Link and Physical) of the seven-layer OSI networking reference model. In fact, IEEE 802 splits the OSI Data Link Layer into two sub-layers named Logical Link Control (LLC) and Media Access Control (MAC), so that the layers can be listed like this:

Data link layer

a LLC Sublayer a MAC Sublayer Physical layer

The IEEE 802 family of standards is maintained by the IEEE 802 LAN/MAN Standards Committee (LMSC). The most widely used standards are for the Ethernet family, Token Ring, Wireless LAN, Bridging and Virtual Bridged LANs. An individual Working Group provides the focus for each area.

Working groups

Name

IEEE 802.1

IEEE 802.2

IEEE 802.3

IEEE 802.4

IEEE 802.5

IEEE 802.6

IEEE 802.7

IEEE 802.8

IEEE 802.9

IEEE 802.10

Description

Bridging (networking) and Network Management

LLC

Ethernet

Token bus

Defines the MAC layer for a Token Ring

MANs

Broadband LAN using Coaxial Cable

Fiber Optic TAG

Integrated Services LAN

Interoperable LAN Security

IEEE 802.11 a/b/g/n Wireless LAN (WLAN) & Mesh (Wi-Fi certification)

IEEE 802.12

IEEE 802.13

IEEE 802.14

100BaseVG

unused

Cable modems

Note

inactive

disbanded

inactive

disbanded

disbanded

disbanded

disbanded

disbanded

disbanded

disbanded

3

IEEE 802

IEEE 802.15

IEEE 802.15.1

IEEE 802.15.2

IEEE 802.15.3

IEEE 802.15.4

IEEE 802.15.5

IEEE 802.16

IEEE 802.16.1

IEEE 802.17

IEEE 802.18

IEEE 802.19

IEEE 802.20

IEEE 802.21

IEEE 802.22

IEEE 802.23

Wireless PAN

Bluetooth certification

IEEE 802.15 and IEEE 802.11 coexistence

High-Rate wireless PAN

Low-Rate wireless PAN (e.g., ZigBee, WirelessHART, MiWi, etc.)

Mesh networking for WPAN

Broadband Wireless Access (WiMAX certification)

Local Multipoint Distribution Service

Resilient packet ring

Radio Regulatory TAG

Coexistence TAG

Mobile Broadband Wireless Access

Media Independent Handoff

Wireless Regional Area Network

Emergency Services Working Group

New (March, 2010)

References a IEEE Std 802-1990: IEEE Standards for Local and Metropolitan Networks: Overview and Architecture New York:1990

[1] http://www.ieee802.org/IEEE-802-LMSC-Overview-and-Guide-01.pdf

External links

802 Committee website (http://www.ieee802.org/) IEEE 802 Standards (http://standards.ieee.org/getieee802)

4

100BaseVG

100BaseVG

100BaseVGis a 100 Mbit/s Ethernet standard specified to run over four pairs of category 3 UTP wires (known as voice grade, hence the "VG"). It is also called100VG-AnyLANbecause it was defined to carry both Ethernet and token ring frame types. 100BaseVG was originally proposed by Hewlett-Packard, ratified by the ISO in 1995 and was practically extinct by 1998. 100BaseVG started in the IEEE 802.3 committee as Fast Ethernet. One faction wanted to keep CSMA/CD in order to keep it pure Ethernet, even though the collision domain problem limited the distances to one tenth that of 10BASE-T. Another faction wanted to change to a polling architecture from the hub (they called it "Demand Priority Protocol") in order to maintain the 10baseT distances, and also to make it a deterministic protocol. The first faction argued that, since IEEE 802.3 was the Ethernet committee, it was not the place to develop a different protocol. Thus, theIEEE 802.12committee was formed and standardized 100BaseVG.

100VG-AnyLAN vs. Fast Ethernet

Multiplexing Instead of following the Fast Ethernet standard for twisted pair cabling by using only 2 pairs of wires, 100VG-AnyLAN used all four pairs in either Category 3 or Category 5 twisted pair cable. The design goals were to avoid the radio frequency radiation emitted at the higher frequencies required by Fast Ethernet and to leverage existing wiring installations of Category 3 cabling that most organizations had recently installed to support 10 megabit twisted-pair Ethernet. This had the additional advantage of being less susceptible to external sources of RF interference such as other network cables, fluorescent lights, and high power lines. They multiplexed the signal across all 8 wires thereby lowering the frequency and making it more robust. This presented a problem with early installations that borrowed one unused twisted pair for telephone traffic but those installations were uncommon.

Deterministic When Ethernet became Fast Ethernet, it continued to use the Carrier Sense Multiple Access With Collision Detection (CSMA/CD) mechanism to manage traffic on the network cable. 100VG took advantage of the token passing concept that made ARCNET and Token Ring popular in order to provide consistent performance no matter how large the network became. It removed the token passing responsibility from the wiring and network nodes and placed it internal to the 100VG-AnyLAN hubs. These hubs contained the rotating token that never left the hub itself. When a node wanted to transmit data, it would raise a bit on its hub port connection that indicating to the hub that it was ready. As the token passed by a ready hub port, it would then open up traffic to that node. Because the token stayed within the hub, it did not have to traverse long cables going to every node as in ARCNET and Token Ring therefore becoming faster than those other deterministic networking standards and being less susceptible to cabling problems, network card failures, and line interference. Real-life load testing showed 100VG-AnyLAN reaching 95% of its theoretical network speed instead of about 45% as in Fast Ethernet when using hubs. Fast Ethernet switches were not commonplace at first because of high cost and limited availability so, initially, 100VG had a significant performance advantage.

5

5 MHz/20 MHz

Generation

6

3G evolution

IA technology enables client terminals which have either multiple antennas or self-tracking directional antenna to communicate each other with as high signal-to-interference-and-noise ratio (SINR) as possible. Assume that there are a source terminal, a destination terminal and some candidate interference terminals. Differently from conventional approaches, an advanced IA based terminal will perform spatial precoding (spatial beamforming and/or spatial coding) not only to enhance the signal power at the destination terminal but also to diminish the interferening

Single-stream beamforming

Examples

IA in ad-hoc networking

20~100 MHz

Lower interference

2012~2015

Ambient intelligence coding

IMT-Advanced

Beyond IMT-Adv

Future

HSPA/HSPA+/LTE

14/42/65~250Mbit/s

Spatial diversity coding

Spatial coding (SC)

Spatial multiplexing coding

Spatial cancellation coding

Deployment

Summary of 3G MIMO The table summarizes the history of 3G MIMO techniques candidated for 3G standards. Although the table additionally contains the future part but the contents are not clearly filled out since the future is not precisely predictable.

Technology Spatial precoding of intelligent antenna includes spatial beamforming and spatial coding. In wireless communications, spatial precoding has been developing for high reliability, high rate and lower interference as shown in the following table.

3G MIMO

Method

References This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.

100BaseVG

3G MIMOdescribes MIMO techniques which have been considered as 3G standard techniques. MIMO, as the state of the art ofIntelligent antenna (IA), improves the performance of radio systems by embedding electronics intelligence into the spatial processing unit. Spatial processing includes spatial precoding at the transmitter and spatial postcoding at the receiver, which are dual each other from information signal processing theoretic point of view. Intelligent antenna is technology which represents smart antenna, multiple antenna (MIMO), self-tracking directional antenna, cooperative virtual antenna and so on.

Spatial diversity

384kbit/s

5 MHz

Standard

Total rate

2003/4

2005~6/2007~8/2009~10

Bandwidth

High reliability (High quality)

3G

Requirement Paradigm

WCDMA

Multi-stream beamforming

Interference nulling beamforming

SC: DPC, SB: MU-BF

Spatial multiplexing

High rate (High capacity)

High intelligence

>10Gbit/s

SC: BLAST coding, SB: SVD

Ambient intelligence beamforming

Such as cooperative MIMO

SC: Alamouti coding, SB: TxAA

>100 MHz

Spatial beamforming (SB)

Ambient intelligence

1Gbit/s

Spatial cancellation

Beyond 3G

2015~2020

3G MIMO

power at interference terminals. As a human does, the advanced IA terminal is given to know that occurring high interference to other terminals will eventually degrade the performance of the associated wireless network.

Comparisons

Intelligent antenna (IA) vs. Cognitive radio (CR) However, it requires intelligent multiple or cooperative antenna array. On the contrary, cognitive radio (CR) allows user terminals to sense the other service usage of spectrum beans to share the spectrum among users, which is so, cognitive spectrum sharing technology. The following table compares the different points between two approach for future wireless systems: Intelligent antenna (IA) vs. Cognitive radio (CR).

Point

Interference processing

Key cost

Solution

Application

Applied theory

Summary

Intelligence antenna (IA)

Cancellation by spatial pre/post-coding

Multiple or cooperative antenna arrays

Intelligent spatial beamforming/coding tech

Ambient Spatial Reuse

Dirty paper and Wyner-Ziv coding (DP-WZ coding)

Intelligent spectrum reuse technology

Cognitive radio (CR)

Avoidance by spectrum sensing

Spectrum sensing and multi-band RF

Cognitive spectrum management tech

Open Spectrum Sharing

Software radio and cognition

Cognitive spectrum sharing technology

Fundamental concepts and theories aIntelligenceis a property of mind that includes many related abilities. aCooperationis the practice of social elements working in common, instead of working individually. aCognitioncan be interpreted as understanding and responding to the world. aAmbient intelligence (AmI)refers to artificial environments that responses to the movement of people, the paradigm of which builds upon Ubiquitous computing. aWireless ubiquitous computing (WUC)is post-desktop computing where information processing is integrated into anytime and anywhere human activities. aGame theoryis a mathematical theory that studies the strategic interaction between players, which are usually organized into a friend group and an enemy group.

Principal Issues of Research The following items list the issues of the multiple antenna research aims to improve the performance of radio communications. a Intelligent antenna a Smart antenna a Multiple-input multiple-output (MIMO) a Beamforming a Diversity combining a Diversity scheme a Space–time code a Spatial multiplexing a Space-division multiple access (SDMA) a Advanced MIMO communications a Multi-user MIMO a Precoding

7