Defining 10GBASE-S over OM4media (Engineered Link)

Steve Swanson, Corning

Adrian Amezcua, Draka

Supporters

• John Abbott, Corning• Gerard Kuyt, Draka• James Lott, VIS Systems• Paul Kolesar, Commscope• Sharon Lutz, USConec• Rick Pimpinella, Panduit• Valerie Maguire, Siemon• Robert Lingle, OFS • Paul Vanderlaan, Nexans

CISCO proposal

Corning-Draka proposal

4700 2 to 400 4700 2 to 500 (1)

• Define an Engineered Link in Table 52-6

• (1) Links longer than 400m are considered engineered links. The cable attenuation and connector allocation needs to be less than that specified in IS 11801. In addition, the maximum spectral width of the VCSEL is a subset of that specified in this standard. For example, with a cable attenuation of 3.0 dB/km, a connector allocation of 1.0 dB and a maximum spectral width of 0.30nm, a 500m link length is supported.

VCSEL characteristics

-3.8 -2.8

CISCO proposal considers worst case sources

500m reach is possible with a subset of sources.

Reducing cable and connectorization loss

BW (MHz.km)

Wavelength (nm)

OMA (dBm) Uw (nm)

Margin@400m (dB)

-3.9 0.25 1.8-3.8 0.3 1.6-3.5 0.35 1.6-3.2 0.4 1.4-2.8 0.45 1.1

4400 840

BW (MHz.km)

Wavelength (nm)

OMA (dBm) Uw (nm)

Margin@400m (dB)

-3.9 0.25 2.5-3.8 0.3 2.4-3.5 0.35 2.3-3.2 0.4 2.1-2.8 0.45 1.8

4400 840

CISCO proposal 3.5dB/km cable attenuation, 1.5dB connector loss.

By reducing the cable attenuation to 3.0dB/km and connector loss to 1.0dB, the margin increases 0.70dB. This extra margin can be used to extend the reach

10GbE reach on OM3 & OM4

• System margin calculations based on IEEE spreadsheet model show that chromatic dispersion ultimately limits the reach of 10GbE on OM4

7

00

0

0

0.5

0.5

0.5

1 1

1

1

1.51.5

1.5

2 22

22.5

2.52.53 3

33

3.5 3.53.5

4 4 4 4

spectral width RMS [nm]

dist

ance

[m

]

0.1 0.2 0.3 0.4 0.5 0.6

50

100

150

200

250

300

350

400

450

500

550

System Marginswith OM3

Connector loss = 1.5dBFiber Attenuation = 3.5dB/kmEMB = 2,000MHz-km

0

0

0.5

0.5

1

1

1.5

1.5

2

2

2

2.5

2.5

2.5

3

3

3

3.5

3.5

3.5

4

4

4

4.5 4.54.5

spectral width RMS [nm]

dist

ance

[m

]

0.1 0.2 0.3 0.4 0.5 0.6

100

200

300

400

500

Connector loss = 1.0dBFiber Attenuation = 3.0dB/kmEMB = 4,700MHz-km

System Marginswith OM4

System Budget with narrow sources (1)

• These calculations are based on central wavelength at 840nm (worst case scenario). The central wavelength of most sources is close to 850nm and at this wavelength the BW of the fiber is >4700MHz.km.

System Margin (Uc=840nm, Uw = 0.30 nm, 4400 MHz.km)

-2

-1

0

1

2

3

4

5

0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65

length (km)

Sys

mte

m M

arg

in (

dB

)3.5dB/km, 1.5 dB

3.0dB/km, 1.0 dB

Reach up to 500m is feasible

System Margin (Uw = 0.30 nm, Cable loss 3.0dB/km, connector loss 1.0 dB)

-2

-1

0

1

2

3

4

5

0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65

length (km)

Sys

mte

m M

arg

in (

dB

)

Uc=840nm,BW=4400MHz.km

Uc=850nm,BW=4700MHz.km

System Budget with narrow sources (2)

BW (MHz.km)

Wavelength (nm)

OMA (dBm) Uw (nm) Margin @500m (dB)

4400 840 -3.8 0.3 0.924700 850 -3.8 0.3 1.32