Tag Archives: 10G SFP+

Comparison of 10GBASE-T and 10G SFP+ Transceiver

With the growing need of higher capacity network connectivity, 10G network transmission is becoming increasingly popular. 10G SFP+ optical transceiver and 10GBASE-T copper transceiver are the two main options of 10G network. It becomes a challenge to choose the appropriate 10G connectivity for every IT worker. This article will compare 10GBASE-T with 10G SFP+ transceiver from the perspectives of power, latency, cost and interoperability. And try to give you some suggestions to choose between them.

Brief Introduction of 10GBASE-T and 10G SFP+ Transceiver Module

10GBASE-T transceiver module and SFP+ optical transceiver are two of the most widely used 10G network connectivity.

10GBASE-T Copper Transceiver

Applied initially in the data center and the horizontal cabling system, 10GBASE-T transceiver module is a new 10GE PHY using the existing MAC (Media Access Controller). It preserves the 802.3/Ethernet frame format at the MAC Client service interface. 10GBase-T works at 100 meters for Cat6a cable and up to 50 meters for Cat6 cable. It offers flexibility, low cost transmission media, and is backward-compatible with existing 1GbE networks.

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10G SFP+ Optical Transceiver

10G SFP+ transceiver is an enhanced version of the SFP transceiver that supports data rates up to 16 Gbit/s. It supports 8 Gbit/s Fibre Channel, 10 Gigabit Ethernet and Optical Transport Network standard OTU2. SFP+ optical transceiver’s connector is duplex LC, and it operates on LC fiber patch cables. SFP+ transceiver is classified in different types, such as SR, LR, ER and ZR. They need to be used with appropriate fiber patch cable, like SR used with multimode fiber patch cable for short distance transmission, while LR, ER and ZR used with single mode fiber patch cable for relatively long links.

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10GBASE-T vs SFP+ Transceiver

After the brief introduction of the two transceiver modules, we will compare them from following perspectives.

Power and Latency

Recent advancements greatly lowered the power consumption of 10GBASE-T server and switch ports. Early versions of 10GBASE-T switches needed up to 12 Watts per port, switch vendors now offer a range of 1.5 to 4 Watts per port depending on distance. In spite of the reduced power consumption of 10GBASE-T transceiver, 10G SFP+ interface uses less power—typically less than 1 Watt per port.

With simplified electronics, 10G SFP+ transceiver also has lower latency—typically about 0.3 microseconds per link. 10GBASE-T transceiver latency is about 2.6 microseconds per link due to more complex encoding schemes within the equipment.

With lower power consumption and lower latency, 10G SFP+ optical transceiver is well suited for large high-speed data centers.

Cost and Interoperability

10GBASE-T switches has been available since 2008, the shipment of 10GBASE-T transceiver module has been increasing over the past years. This proliferation helps to drive down the cost of 10GBASE-T technology. With 10GBASE-T technology’s wide application, the use of 10G SFP+ transceiver module means additional cost for the servers equipped with 10GBASE-T NIC card. Comparing one of the latest 10G SFP+ and 10GBASE-T switches, the cost of 10GBASE-T transceiver ranges from 20% to 40% less.

10GBASE-T copper transceiver also has the advantage of being interoperable for using the familiar RJ45 connector and providing backwards compatibility with legacy networks. So it can be deployed in existing 1GbE switch infrastructures in data centers, enabling IT to keep costs down while offering an easy migration path to 10GbE. While 10GSFP+ optical transceiver are limited with little or no backwards compatibility.

Make an Informed Decision

When you choose between 10GSFP+ optical transceiver and 10GBASE-T copper transceiver, consider your needs carefully. If lower power consumption and lower latency are significant, 10GSFP+ transceiver might be the better choice for you. If lower cost and better Interoperability are important, 10GBASE-T transceiver might be more suitable for you. FS provides an extensive selection of 10GBASE-T, 10G SFP+ transceiver and transceiver module of other data rate, such as 1G, 25G, 40G, 100G and so on. For more details about FS 10GBASE-T transceiver module and 10G SFP+ optical transceiver, please contact us at sales@fs.com.

10GBASE-T vs SFP+ vs SFP+ Cable, Which to Choose for 10GbE Network?

The dramatic growth in data center requires the higher-performance servers, storage and interconnects. From initial 100M, 1G, 10G, to 40G and 100G, high speed Ethernet has never stopped developing. The standard for 10 Gigabit Ethernet (IEEE802.3ae) was ratified in 2002. In 10 Gigabit Ethernet, there are mainly three media: 10G SFP+ transceiver, SFP+ DAC cable and 10GBASE-T SFP transceiver. This post will discuss 10GBASE-T vs SFP+ vs SFP+ cable.

Media Options for 10GbE Network: 10GBASE-T vs SFP+ vs SFP+ Cable

10G SFP+

SFP+ (small form-factor pluggable plus) supports both fiber optic cables and DAC (direct attach cable). It delivers a wide variety of 10GbE Ethernet connectivity options for data center, enterprise wiring closet, and service provider transport applications. But it has the limitations that will prevent the media from moving to every server.

SFP+ Cable

SFP+ cable is designed for 10GbE access layer interconnection in data center. It includes direct attach copper cables and active optical cables. DAC is a lower cost alternative to fiber, but it can support limited transmission distance and it’s not backward-compatible with existing GbE switches. DAC requires the purchase of an adapter card and requires a new top of rack (ToR) switch topology. DAC is more expensive than structured copper channels, and cannot be field terminated.

10GBASE-T SFP

10GBase-T SFP enables 10GbE connections with unshielded or shielded twisted pair cables over distances up to 100 meters. 10GBase-T technology appears as SPF is not compatible with twisted pair cabling system typically used in data centers. With 10GBase-T SFP, the migration from 1GbE to 10GbE can be easily achieved.

10GBASE-T vs SFP+ vs SFP+ Cable

This part will dicuss 10GBASE-T vs SFP+ vs SFP+ Cable from the aspects of latency and power consumption:

Latency

Low latency becomes so important since the adoption of private cloud applications increases. It’s beneficial for ensuring fast response time and reducing CPU (center processing units) idle cycles so that improve data center efficiency.

As to 10GBASE-T SFP, the physical connection (PHY) standard uses block encoding to transport data across the cable without errors. The block encoding requires a block of data to be read into the transmitter PHY, a mathematical function run on the data before the encoded data are sent over the link. It happens the same on the receiver side. This standard specifies 2.6 microseconds for the transmit-receive pair, and the block size requires latency to be less than 2 microseconds. While 10G SFP applies simplified electronics without encoding, and common latency is around 300 nanoseconds per link.

You may think that two microseconds are not high. But what if a TOR infrastructure where traffic is passing 4 hops to reach the destination? 10.4-microsecond delay will be caused when using 10GBASE-T SFP. The following table tells details about the latency of SFP+ cable, 10G SFP and 10GABSE-T SFP for different number of links.

Number of Links SFP+ Cable Latency 10G SFP Latency 10GBASE-T SFP Latency
1 0.3 0.1 2.6
2 0.6 0.2 5.2
3 0.9 0.3 7.8
4 1.2 0.4 10.4
5 1.5 0.5 13.0
6 1.8 0.6 15.6

From the above table, it shows that the latency of 10GBASE-T SFP is the highest. As network links grow, the latency turns to be higher. It’s known that the lower latency, the faster the network speed. High latency in the data center infrastructure results in delays in CPU and application works, therefore limiting data center efficiency and increasing operational costs.

Power Consumption

Power consumption is also one of the important factors to be considered in data centers. Engineers are sensitive to power consumption and find a way to seek the lowest possible power consumption technologies. It’s said that every watt of power consumed, typically two additional watts are needed for cooling.

10GBase-T components today require anywhere from 2 to 5 watts per port at each end of the cable depending on the distance of the cable. But 10G SFP requires about 0.7 watt regardless of distance. The figure below compares the power consumption of three media options of 10GbE Ethernet.

10GBASE-T vs SFP+ vs SFP+ Cable

From this figure, suppose there are 10000 ports in the data center, 10G SFP can greatly save the power. On contrary, 10GBASE-T components consumes the most power. Thus, to save power in the data center, 10G SFP and SFP+ cable should better be selected when deploying thousands of cables in a data center.

Conclusion

From this article, 10G SFP+ and SFP+ cable solutions are better than 10GBASE-T SFP for 10G data center. But 10GbE is not the ultimate goal. Besides factors mentioned in this article, you should also select a cabling solution which can support not only current needs but also future data center deployments when you design 10GbE network. You can find various SFP+ modules and 40G QSFP+ from FS.COM.

Related article: How to Convert SFP+ to 10GBASE-T/RJ45?