100GbE_Overview_white_paper(2)

With approved objectives and PAR, the IEEE 802.3ba Task Force was formed in December of 2007. The task force has been meeting regularly to discuss technology proposals that are nearing finalization (expected in early 2010).

The approved task force objectives were:

Exclusive support full-duplex operation

Preserve the 802.3 Ethernet frame format using the 802.3 MAC

Preserve the current 802.3 standard minimum and maximum frame sizes

Support bit error rates better than or equal to 10-12 at the MAC/PLS service interface Provide appropriate support for optical transport networks (OTN)

Support a MAC data rate of 100 Gbps, with physical layer specifications that support operation over:

At least 40 km on SMF fiber

At least 10 km on SMF fiber

At least 100 m on OM3 MMF

At least 10 m over a copper cable assembliesThe High Speed Study Group reached the conclusions that both 100 GbE and 40 GbE solutions should be pursued.

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100GE以太网技术介绍

In May 2009, Ixia demonstrated the world’s first 100 Gb/s test module with a CFP interface.

6 Support a MAC data rate of 40 Gbps, with physical layer specifications that support opera-tion over: At least 10 km on single-mode fiber (SMF) fiber At least 100 m on OM3 multi-mode (MMF) fiber At least 10 m over a copper cable assemblies At least 1 m over a backplaneIn June 2008, at the NXTcomm’08 trade show, Ixia demonstrated the operation and testing of a 100 Gbps link based on the current state of their standardization efforts. In October 2008, Ixia unveiled a 100 Gbps Development Accelerator System for sale and demonstrated a 40 Gbps proof-of-concept system. In May 2009, Ixia demonstrated the world’s first 100 Gbps test module with a CFP interface.Higher.Speed.TechnologyUse.of.Existing.FiberOne of the task force’s recommendations was to use existing fiber connectors. In particular, the most common fiber cable types should be accommodated: 100 m multi-mode fiber (MMF) using a 850 nm wavelength, 10 km single-mode fiber (SMF) using 1310 and 1550 wavelengths, and 40 km single-mode fiber (SMF) using 1310 and 1550 wavelengths Advances in wavelength-division multiplexing (WDM) and dense-WDM (DWDM) enabled the use of multiple simultaneous wavelengths on individual fibers, each capable of 10 Gbps traffic. Today’s optical transport networks uses DWDM to implement ITU-T recommendation G.709, which defines ODU4 for use with 100 Gbps and ODU3 with 40 Gbps. Work is progressing toward higher bandwidth per wavelength and fiber. Industry pundits see near-term bundles of various combinations that will handle 100 Gbps information flows, including: 10 wavelengths of 10 Gbps 4 wavelengths of 25 Gbps 5 wavelengths of 20 GbpsNot.reinventing.the.wheelThe 802.3ba task force’s guidelines include leaving the majority of 802.3 standards in place. Figure 4 is a typical Ethernet architecture as it applies to 40 and 100 Gbps.

100GE以太网技术介绍

The 802.3ba task force’s guidelines include leaving the majority of 802.3 standards in place.

Figure 4. 40/100 Gbps Ethernet Architecture

No changes will be made to the medium access control (MAC) layer beyond increasing the data rates to 40 and 100 Gbps. This means that other characteristics, including frame format, mini-mum/maximum frame sizes, and full-duplex only operation remain the same.

The reconciliation sublayer (RS) maps the MAC’s serial bitstream into its respective 40 and 100 Gbps media independent interfaces. These interfaces are being developed based on the earlier XGMII (10 Gbps) interface: CGMII (100 Gbps) and XLGMII (40 Gbps). These interfaces in the architecture along with the components that use these interfaces are being standardized through multiple multi-source agreements (MSAs) between industry component vendors , such as the CFP MSA (see the transceiver section below).

The remaining sublayers serve to serialize the data received through the MII and present it to the copper or optical medium. The physical coding sublayer (PCS) provides coding, including scram-bling and control block encoding. 64/66b coding, as used in 10GBASE-R, is the choice for these higher speeds. The optional FEC sublayer performs encoding for forward error correction. The physical medium attachment (PMA) sublayer serializes the coded data as required by the medium. The physical medium dependent (PMD) sublayer is responsible for signaling of the serial stream to the medium through the media dependent interface (MDI).

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100GE以太网技术介绍

Pluggable transceiver modules compliant to the CFP MSA are an option for 40 and 100G Gbps interfaces.

8Transceiver.OptionsAs the IEEE moves forward in finalizing the 40 Gbps and 100 Gbps standard P802.3ba, many wonder which transceiver type will win out as the final industry higher speed Ethernet connec-tor. With the recent formation of a new multi-source agreement (MSA) between several of the top transceiver manufacturers (Avago, Finisar, Opnext, and Sumitomo), it appears that hot-pluggable optical CFP transceivers are the clear front runner.Both the OIF and the ITU-T are working on standardizing SDH/OTN telecom interfaces for long-haul transmission of 100 Gbps. The CFP MSA defines a hot-pluggable optical transceiver form factor to enable 40 and 100 Gbps applications. Pluggable CFP transceivers will support the ultra-high bandwidth requirements of data communications and telecommunication networks that form the backbone of the internet.Pluggable transceiver modules compliant to the CFP MSA are an option for 40 and 100 Gbps interfaces. The CFP MSA is defining the specifications required to support multiple applications using the same form factor. These applications include various protocols (such as 40 Gbps, 100 Gbps, OC-768/STM-256, OTU3), media types (multimode and single mode fiber optics), and link distances …… 此处隐藏：5933字，全部文档内容请下载后查看。喜欢就下载吧 ……