10 gigabit ethernet - hsn
TRANSCRIPT
10 10 Gigabit EthernetGigabit Ethernet
Sungsoo Kang
Network Technology DivisionETRI
2ETRI Proprietary
차차 례례
Background & reviewFrom 10Mb/s to 1 Gb/s Ethernet
10GbEBackground & activityTechnical detail
10GbE prospective
3ETRI Proprietary
Ethernet history Ethernet history -- originoriginALOHA
Based on contention of broadcast (air) channelPure ALOHASlotted ALOHA
Pack
et PacketPack
etPacket
4ETRI Proprietary
Pure ALOHA collisionPure ALOHA collision
Extremely inefficient, since the worst-case period of vulnerability is the time to transmit two frames.
Collides withthe start ofthe shaded
frame
Collides withthe end ofthe shaded
frame
Vulnerabletimet0 + 3tt0 + 2tt0 + tt0
t
5ETRI Proprietary
Robert Metcalf’s Idea – borrow ALOHA’s idea to LANWith adding collision detection by carrier sensing
Now, let see MAC protocol
• Invented by Metcalf at Xerox in 1973 and patented in 1976
• Xerox, Digital and Intel jointly made DIX.xx
• IEEE standard in 1989
Invention of EthernetInvention of Ethernet
of the first Ethernet designof the first Ethernet design
6ETRI Proprietary
Ethernet History: CSMA/CDEthernet History: CSMA/CD
Take Slotted ALOHA to the next level, use the slots as “contention periods”.
If no collision occurs before the end of the period, then complete transmission of the frame.
CSMA/CD can be in one of three states: contention, transmission, or idleVariable length of packet
FrameFrameFrame Frame
transmissionperiod
contentionperiod
idleperiod
contentionslots
time
t0
7ETRI Proprietary
Ethernet LAN Ethernet LAN 발전발전
1973
1980
1990
2000
2002
10 Mbps
100 Mbps
1,000 Mbps
10,000 Mbps
Xerox Ethernet2.94 Mbps
Ethernet10BASE5(80) : Thick Coaxial802.3a&b(85) : Thin Coaxial 802.3i(90) : UTP3(or better)802.3j(93) : Fiber
Fast Ethernet802.3u(95) : UTP3&5, Fiber 802.3y(97) : UTP3
Gigabit Ethernet802.3z(98) : Fiber, STP802.3ab(99) : UTP5
10Gigabit Ethernet802.3ae(02) : Fiber Only
Ethernet Standards Approval Timeline
1995
1998
FDX/
Flow
con
trol
,A
uto-
nego
tiatio
n
Car
rier 확장
,Pa
cket
bur
stin
g
FDX
only
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Change of Market DriversChange of Market Drivers
6000
5000
4000
3000
2000
1000
0
voice data97 98 99 00 02 03 04 05 06 0701 08
Global Voice / Data Crossover
Gbp
s
Source: A.D. Little Source: The Yankee Group
100
50
200019991998 2001 2002B
illio
ns o
f Dol
lars
150
200
0
Voice and Data Revenue Growth
voice data
Source: NGN Ventures 2000
9ETRI Proprietary
Circuit traffic : increase 8~10 % per yearPacket traffic : increase 200 % per yearHow do we efficiently collect traffic from Access and Metro Area Networks ??
10 Gig Ethernet might be best candidate
Issues Issues ……
10ETRI Proprietary
Gigabit BW vs. ASPGigabit BW vs. ASP
Ethernet이 SONET 보다 85%정도 저렴할 것으로 예상− 10Gigabit Ethernet : $950(2001), $485(2004)− OC-192 SONET : $7,653(2001), $3,143(2004)
ASP(Average Selling Price), Normalized to 1Gbps Service.
Ethernet SONET
Source : Dell’Oro Group
11ETRI Proprietary
What is 10Gig Ethernet?What is 10Gig Ethernet?
Most simple way to expand enterprise & service provider’s networkCan use already installed more than 300 million Ethernet switch portSupport all data serviceSupport not only LAN but also MAN, WANSimple, cheap and fast comparing to competitive technologiesMatch to MAN/WAN backbone speed(OC-192)Support all link without protocol conversion !!
12ETRI Proprietary
802.3802.3ae. schedule & plausible scenarioae. schedule & plausible scenario
1999 2000 2001 2002
HSSGformed
PARdraft
PARapproved
802.3aeformed
WGballot
Firstdraft
LMSGballot standard
Dra
ft 1
Dra
ft 2
Dra
ft 3
Dra
ft 4
Dra
ft 5
10 GbE Standard draft near complete.Vendors build pre-standardproducts based on draft
Commodity10 GbETransceiversHit the market
Commodity10 GbE Solutions
in market
2003
Committee is waiting for enough prototypes
13ETRI Proprietary
IEEE P802.3ae ObjectivesIEEE P802.3ae Objectives
Preserve 802.3 Ethernet frame formatPreserve 802.3 min/max frame sizeFull duplex operation onlyFiber cabling only10.0 Gbps at MAC-PHY interfaceLAN PHY data rate of 10 GbpsWAN PHY data rate of ~9.29 Gbps
14ETRI Proprietary
10GBASE-W is subset of 10GBASE-R
10GBASE-X− 10GBASE-LX4
10GBASE-R− 10GBASE-SR− 10GBASE-LR− 10GbASE-ER
10GBAE-W− 10GBASE-SW− 10GBASE-LW− 10GBASE-EW
1010Gig Ethernet Reference ModelGig Ethernet Reference Model
LLC-LOGICAL LINK CONTROL
MAC CONTROL (OPTIONAL)
MAC-MEDIA ACCESS CONTROL
RECONCILIATION
64B/66B PCS
WIS
PMA
PMD
64B/66B PCS
PMA
PMD
8B/10B PCS
PMA
PMD
XGMIIXGMIIXGMII
MEDIUMMEDIUM MEDIUM
MDIMDIMDI
10BASE-W 10BASE-X10BASE-R
PHYSICAL
DATA LINK
NETWORK
TRANSPORT
SESSION
PRESENTATION
APPLICATION
OSI
Ref.
model
Higher layers
MDI = Medium Dependent Interface PMD = Physical Medium Dependent
PCS = Physical Coding Sub-layer WIS = WAN Interface Sub-layer
PHY = Physical Layer Device XGMII = 10 Gigabit Media Independent Interface
PMA = Physical Medium Attachment
PHYPHY
15ETRI Proprietary
802.3802.3ae/z/ab Distance Chartae/z/ab Distance Chart
Campusbackbones
Buildingbackbones
Wiringcloset
1000BaseCXCopper
9 µm SMF
50 µm / 62.5 µm MMF
50 µm MMF
62.5 µm MMF
4 pairUTP 5
1000BaseLX~ 1300 nm
1000BaseSX~ 850 nm
1000BaseT1999 (802.3ab)
25 m 275 m 550 m 5 km
GbE
300 m65 m
MAN / WAN
> 40 km
62.5 µm MMF, WWDM
50 µm MMF, serial
1310 nm
850 nm
9 µm SMF, serial
9 µm SMF, serial & WWDM
1550 nm
1310 nm
> 10 km
10 G
bE
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Nomenclature Nomenclature && Clause(2)Clause(2)
Nomenclature
clause
48
8b/10bPCS &PMA
10GBASE-SR
10GBASE-SW
10GBASE-LX4
10GBASE-LR
10GBASE-LW
10GBASE-ER
10GBASE-EW
49
64b/66bPCS
50
WIS
51
SerialPMA
54
1310 nmWWDMPMA
850 nmserialPMA
52
1310 nmserialPMA
1550 nmserialPMA
Ref: IEEE Draft P802.3ae/D 2.3, March 2001
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10 10 Gig Ethernet PHYGig Ethernet PHY
PMA – Physical Media AttachmentSerialization/Deserialization(SerDes)Octet delineation[SONET framing][Scrambling function for SONET frame (x7 + x6
+ 1)]PCS – Physical Coding Sublayer
MAC packet delineation & Header control64B/66B CodingScrambling function for data (x43 + 1)
PMD – Physical Media Dependent interfaces
OpticsClock Recovery
MAC
PHY
PMD
PMA
PCS
18ETRI Proprietary
1010GBASEGBASE--XX
Ethernet Packet + min . IPG
8b
10b
8b/10bencoder
SERDES
8b
10b
8b/10bencoder
SERDES
8b
10b
8b/10bencoder
SERDES
8b
10b
8b/10bencoder
SERDESPMA
8b/10b PCS
MAC 10 Gbps
XGMII
10 Gbps
12.5 Gbps,4 @ 3.125 Gbps
12.5 Gbps,4 @ 3.125 Gbps
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Ethernet Packet + min . IPG
SERDESPMA
64b/66b PCS
MAC 10 Gbps
XGMII or XAUI
10 Gbps
10.3 Gbps
10.3 Gbps
XSBI
64 bit scrambler
64bSync. Bits (2)
1010GBASEGBASE--RR
64b 64b 64b 64b64b 64b
20ETRI Proprietary
PMA
64b/66b PCS
MAC 10 Gbps
XGMII or XAUI9.29 Gbps
9.58 Gbps
9.95 Gbps
XSBI
Extra IPG
Extra IPG dumpedExtra IPG dumped
simplified SONET framersimplified SONET framerWIS 9.95 Gbps
1010GBASEGBASE--W(1)W(1)
Ethernet Packet + min . IPG
SERDES
64 bit scrambler
64b 64b 64b 64b64b 64b
64bSync. Bits (2)
21ETRI Proprietary
RSOH
MSOH
Transport
Overhead
(STS-192c) Envelope Capacity
IDLE packetPCS data stream
Path Overheadcolumn
WIS Frame = STS-192c Frame
9 ro
ws
576 octets 17280 octets
(STS-192c) SPE
116704 octets
1664063
9 ro
ws
Payload Capacity
IDLE packet
IDLE
IDLE
Fixedstuff
1010GBASEGBASE--W(2)W(2)WIS is to allow to 10GBASE-W equipment to generate Ethernet data streams that may be mapped directly to STS-192c or VC-4-64c streams at the PHY levels, without requiring MAC or higher-layer processing.
STS-192c = Synchronous Transport Signal level 192, c=concatenatedSPE=Synchronous Payload Envelope
22ETRI Proprietary
Structure of SONET OverheadStructure of SONET Overhead
pointer
MSOH
RSOH
POH
J1
B3
C2
G1
F2
H4
Z3
Z4
Z5
E1 F1
D1 D2
B2 K1
S1 M1
J0A1 A2 Z0A1 A1 A2A2
B1 ∆ ∆ ∆ X X
∆ ∆ ∆ D3
H1 H1 H1 H2 H2 H2 H3 H3 H3
B2 B2 K2
D6D5D4
D9D8D7
D12D11D10
E2 ∆∆
Z0A1 …
∆ …
∆ …
B2 …
H1 …
D4
D7
D10
A2 …
∆ …
∆ …
…
H2 …
D5
D8
D11
Z0 …
∆ …
∆ …
…
H3 …
D5
D8
D11
321 193 385 576
23ETRI Proprietary
WIS for SONET OHWIS for SONET OH
Only minimum SOH process for OC-192c interfacePointer process (H1-H2, H3)Automatic protection (K1,K2)Framing & regenerator (A1, A2, J0, Z0)Error check, Mux error monitor & remote error indicator (B1, B2, M1, S1)Others : un-supported (DCC, order wire, sync. etc.)
Only 1349 octets are defined in WIStotal:5184 octets Overhead(SOH, LOH) are defined in SONET
Also minimum POH process for OC-192c interfaceSTS path signal label (C2)STS path trace (J1)Others : un-supported (H4, F2, Z3, … etc.)
24ETRI Proprietary
1010GBASEGBASE--W is SONET FriendlyW is SONET Friendly
SONET friendly does NOT mean SONET compliant…
SONET frame (bits) are SONET compliantNo layer 2 bridging requiredOverhead will be interoperable with existing equipment
Does NOT meet SONET jitter requirementsmatch the ITU Grid
Does NEED a PHYSICAL layer conversion
25ETRI Proprietary
Hardware implementation issueHardware implementation issue
XGMII is interface between MAC and PHYShort reach interface: XGMII is ~ 7 cmNeed to extend reach for many 10GbE port
Reconciliation sublayer PHY
Station management
XGMII = 10 Gigabit Media Independent Interface
36
1
XGMII signals
(serial 2 wire interface)
TXC (transmit clock)
TXD (32 data bits, 4 control bits)
RXC (receive clock)
RXD (32 data bits, 4 control bits)
MDIO
MDC
36
1
1
1
26ETRI Proprietary
Extending reach for implementationExtending reach for implementation
LLC-Logical Link Control
MEDIUM
Physical Medium Dependent (PMD)
Physical Coding Sublayer (PCS)
Physical Medium Attachment (PMA)
MAC Control (Optional)
XGMII
XAUIXGXS
XGXS
Reconciliation
Media Access Control (MAC)
XGMII
PHYSICAL
DATA LINK
NETWORK
TRANSPORT
SESSION
PRESENTATION
APPLICATION
OSI
Ref.
modelOptional XGMIIeXtender
PHY
Higher Layer
27ETRI Proprietary
InterfacesInterfaces
XGMII (10G Media Independent I/F)4 byte-wide lanes with 1 control bit per lane
XAUI (10G Attachment Unit I/F)Extends XGMII reach (3” vs. 20”)4 differential lanes at 3.125 Gbps
XSBI (10G Sixteen-Bit Interface)Based on the OIF SFI-4 interface16 differential signals at 622-645 Mbps
28ETRI Proprietary
XAUIXAUI
XAUI : 10 Gigabit eXtended Attachment Unit InterfaceXGXS : XGMII eXtender SublayerIncreased reach
XGMII is ~ 7 cmXAUI is ~ 50 cm
Lower connection countXGMII is 74 wires (2 sets of 32 data, 4 control & 1 clock)XAUI is 16 wires (2 sets of 4 differential pairs)
3.125 Gbaud, 8B/10B encoded over 50cm FR-4 PCB tracesCDR-based, 4-lane serial, self-timed interfaceMay be implemented in CMOS, BiCMOS, SiGeDirect mapping of RS/XGMII data to/from PCS
http:// grouper.ieee.org/groups/802/3/ae/public/may00/taborek_2_0500.pdf
29ETRI Proprietary
XGXS functionXGXS function
8B/10B transmission codeColumn stripping across 4 independent serial lanes
Identified as lane 0, lane 1, lane 2, lane 3Perform XAUI lane and interface(lane) synchronizationPerform lane-to-lane deskewProvide packet delimitersPerform error control to prevent error propagation
30ETRI Proprietary
Issues on Optical moduleIssues on Optical module
10 GbE PMD and distances
300 meter, 850 nm – VCSEL
2 Km, 1310 nm – Fabry-Perot laser, singlemode
10 Km, 1310 nm – DFB laser or VCSEL, singlemode
40 Km, 1310 nm – DFB laser, cooled, singlemode
40 Km, 1550 nm – DFB laser, singlemode
Source: Business Communication Review, April,2000
31ETRI Proprietary
Two type of LASERTwo type of LASER
SIOAlGaAsGaAs MQWAlGaAs
p-n junction boxbase oftransistorcan
Mounting postLaser beamoutput
Semiconductorsample(GaAs)
fine wirecontact
Conventional LD
Gainregion
Oxidelayer
current
Top layer(99.9% reflective)
Bottom layer(99.9% reflective)
Laser cavity(length)
VCSEL
32ETRI Proprietary
Prospective on VSCELProspective on VSCEL
Comparison with Edge-emit LDVertical : longitudinal structureCircular : elliptical coupling efficiency 80% : 10%Low threshold currents (typically less than 1 mA)Very stable over temperature performanceYield improvement
On wafer : after wafer & individually
Trends850 nm commercially available now1310 nm just announced ~ 10 Km with range1550 nm by end of 2001, be announced
33ETRI Proprietary
Optical Fibers
Interface +Tx/Rx
Electronics
XGP Transceiver
4Lanes
FromUpper
Layer IC
ToUpper
Layer IC
O/E
4Lanes
..
..
..
..
..
..
Interface +Tx/Rx
Electronics
XGP Transceiver
4Lanes
ToUpper
Layer IC
FromUpper
Layer IC
O/E
4Lanes
..
..
..
..
..
..
transceiver
Connector plugCage assembly
Bezel
Connector Receptacle
XGP MSA GroupXGP MSA Group
Muti Source Agreement(MSA)SFP(Small Form-Factor Pluggable)
14 Participating Transceiver CompaniesTarget IEEE 802.3ae, other 10Giga standardSupport 4 lane electrical interfacewww.xgpmsa.org
34ETRI Proprietary
GbEGbE: Typical Implementation: Typical Implementation
Logical Link Control
Physical Medium Dependent
Physical Coding SublayerPhysical Medium Attachment
MAC Control (Opt)
(XG)MII
Reconciliation SublayerMedia Access Control
Media
802.3 Layer Model
MDI
35ETRI Proprietary
Typical Gigabit Optical Typical Gigabit Optical XCVRsXCVRs
1x9 GBIC
SFF
SFPPluggable
Pin in Hole
36ETRI Proprietary
Early 10 Gigabit Optical XCVRSEarly 10 Gigabit Optical XCVRS
XGXSFTRX
XENPACK
37ETRI Proprietary
Summary of 10 Gigabit EthernetSummary of 10 Gigabit Ethernet
MACIt’s just Ethernet
Maintains 802.3 Frame Format and SizeFull Duplex operation only
PHYLAN PHY uses simple encoding mechanisms to transmit data on dark fiber & dark wavelengthsWAN PHY adds a SONET framing sublayer to enable transmission of Ethernet on SONET transport infrastructure
PMDSupport distances from 65m on installed MMF to 40km on SMF
No copper solution proposed
38ETRI Proprietary
10 10 GbE in the LANGbE in the LAN
10 GbE in service providerdata centers & enterprise LANsSwitch to switchSwitch to serverData centersBetween buildingsServer
Farm
10GbE
Data Center
Campus ACampus B
10GbE
10GbE10GbE
InternetExtranet
10 GbE SMF
10 GbE MMF100 to 300 m
2 to 40 Km2 to 40 Km2 to 40 Km
39ETRI Proprietary
Location B
Location A
10GbE
10GbE
MetroMetro
Remote Servers
Location C
10GbE
10GbE
10GbE
10GbE
10 10 GbE in the MANGbE in the MAN
MetropolitanNetworks
Enterprises:Enables dark fiber to become a 10 Gbps fat pipe for metro networks
Service Providers: enables Gigabit services at costs less than T3 or OC-3
40ETRI Proprietary
10 10 GbE in the MAN over DWDMGbE in the MAN over DWDM
Enterprises:10 GbE enables serverless buildings,remote backup, disaster recovery
Service Providers: 10 GbE enables dark wavelengthGigabit services at costs less than T3 or OC-3MAN DWDM Optical
Network
Location B
Location A
10GbE
Remote Servers
Location C
10GbE
10GbE
DWDM mux
Distance: 100 kmDistance: 100 km
41ETRI Proprietary
Carrier DWDM device collocated with SP 10 GbE Switch
Core DWDM Core DWDM Optical NetworkOptical Network
10GbE
Service Provider Point of Presence
(PoP)CarrierCentral
Office (CO)
10GbEOpticalTransport
OpticalTransport
CarrierCentral
Office (CO)
Service Provider Point of Presence
(PoP)
10 10 GbE in the WANGbE in the WAN
Attachment to the optical cloud with WAN physical layerCompatibility with the installed base of SONET OC-192 Interface & link between SP to IXC network can be co-locatedNo need for protocol conversion, traffic remains IP/Ethernet
NationalBackbone
42ETRI Proprietary
Issues for 10GbEIssues for 10GbE
WAN interconnection
Market issue
Industry issue
What’s our next step ?
43ETRI Proprietary
‘‘PathPath’’, , ‘‘LineLine’’, , ‘‘SectionSection’’
Line TerminatingEquipment
(LTE)
Section Section
Line
Path(s)
Stratum Clock
Regenerator(STE)
LocalClock
LocalClock
Note: A Line can be longer than two Sections
Path TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)Path
TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)
Path TerminatingEquipment
(PTE)
Line TerminatingEquipment
(LTE)
44ETRI Proprietary
Layer Diagram of ELTELayer Diagram of ELTE
Layer 1 Path Relay
SONETPhysical Media Adaptation
SONETSection Termination
SONETLine Termination
802.3 Link Segment SONET OC-192c
Ethernet Line Terminating Equipment (ELTE)
The client-side link (private network) uses Ethernet optics and implements part of the WAN Interface Sublayer (terminates section and line overhead)
The system-side link (to public network) contains an OC-192c or OC-768 SONET LTE
A Layer-1 Path Relay transports the SPE from the client side to the system side and vice versa
Source: PMC-Sierra, T1X1.5,2001, May
802.3 WANPhysical Medium Attachment
802.3 WANPhysical Medium Dependent
PartialWAN Interface Sublayer
λ A λ B
802.3 MAC
64B/66BPhysical Coding Sublayer
WAN Interface Sublayer
802.3 WANPhysical Medium Attachment
802.3 WANPhysical Medium Dependent
Higher Layers
Reconciliation Sublayer
45ETRI Proprietary
Cost prediction onCost prediction on GbEGbE & 10GbE& 10GbE
동향 예측GbE 동향 예측
스위치: $1,400 (1999) $550 (2004)NIC : $ 570 (1999) $ 80 (2004)
10GbE 동향 예측
스위치: $2,800 (2000) $2,000 (2004)NIC : $3,000 (2001) $1,200 (2004)
출처: Linley Group, June 2001
46ETRI Proprietary
Trend on 10GbE industriesTrend on 10GbE industries
Chip set trend장미빛사진 ? (10GbE Transceiver가 Agere의경우 2003년대량출하시 WWDM XAUI가 $1000수준으로예상(uncooled DFB LD)
메트로응용을위한 10GEA 결성및 MEF, RPR표준화추세10GEA: 2001년1월결성, ETRI포함 111개회사/기관메트로이더넷포럼: 2001년10월결성, 60여개제조사및통신사업자IEEE802.17 결성, 2003.3 까지 RPR표준화목표
10GbE카드출시공고시스코: 비표준의 1550nm, 50Km 공고(CISCO12000시리즈용), $80,000/cardAvaya: 850nm/1310nm/1550nm($20,000 ~ $60,000)을 2002.01 출시공고Ethernet system itself is still not yet
10G급 NPU, Switch개발동향EZchip: 2000.10까지 $28M fundingXelerated: $12M funding (2001.10)Silicon Access: $85 M fundingIBM의경우, 자사의 10G급 switch fabric은 Ezchip과 interoperability
IEEE802.3ae동향:정식표준확정의지연예상(wait for enough prototype)Source: Network World High-speed LANs news letter, Aug., 2001, by Jeff Caruso
47ETRI Proprietary
Next, Next, 40GbE40GbE or or 100GbE100GbE ????
20062002
1998
1995
1990198310
100
1,000
10,000
100,000
1980 1985 1990 1995 2000 2005 2010
Meg
abits
per
sec
ond
10BASE-T
Fast Ethernet
Gigabit Ethernet
10 Gigabit Ethernet
Moore’s L
aw
10BASE-T
Fast Ethernet
Gigabit Ethernet
10 Gigabit Ethernet
48ETRI Proprietary
Next Speed Increase? Next Speed Increase?
50% of 802.3ae thinks next speed should be 40 GbE
People are already talking about combining 10 GbE Serial with 4 Color WDM to provide 40 GbEEthernet Utilizing 802.3ad (link aggregation)Or, does this mean OC-768-like?
But, 100 GbE is not unlikely (year 2006) ??
49ETRI Proprietary
referencesreferences
TextbookJ. Kadambi, et. al, “Gigabit ethernet”, prentice hall, 2000
Tanenbaun, “Computer Network”, 5th edition, 2000
윤종호, “고속 이더넷”, 1996, Ohm사
강철희외 3인 공역, “그림으로 보는 기가비트 이더넷,” 2000, 교보문고
Other useful articles …IEEE 802.3ae, http://rouper.ieee.org/groups/802/3/ae/index.html
10GEA White Papers, http://www.10gea.org
C.Simoneaux & J. Jewell, “MSA Group overview and status report”, IEEE 802.3ae interim meeting, Sept., 2000
H. Kaplan & B. Noseworthy, “The Ethernet: Evolution from 10 to 10,000 Mbps – How it all works!”, N+I 2000 Atlanta workshop
Optical Ethernet, http://www.optical-ethernet.com/optical/index.htm
IEEE 802.3, http://www.ieee802.org/3/efm/index.html