The past few years have witnessed the extensive adoption of 10Gbps connectivity at data center equipment. The expansion of 10GbE is supposed to satisfy the increasing demand for higher-performance servers, storage and interconnects. Since 10G network generally provides both optical and copper options, here comes the challenge for every IT technician: how to select the appropriate 10GbE cabling solution? And could it be able to support data center deployments and trends concerning current situation and the future? This article addresses the tradeoffs between the effective choices in copper connectivity 10GBASE-T and SFP+.
With the increase in server consolidation through virtualization in the data center, the resulting data demand has exceeded traditional 1Gb/s throughput capabilities. Gigabit Ethernet connections can handle the bandwidth requirements of a single physical server, but they are inadequate to support virtualized server-consolidation scenarios, or multiple traffic types during peak periods. Today these virtualized servers are typically configured with multiple 1Gb/s ports in order to keep up with the I/O demands. Moving to 10GbE overcomes these 1Gb/s bandwidth limitations by providing more bandwidth and simplifies the network infrastructure by consolidating multiple gigabit ports into a single 10GbE connection.
Let’s take a minute to review the pros and cons of SFP+ and 10GBase-T (IEE 802.3an-2006) so you can make an informed decision and select the solution that best fits your need.
Advancements allow switch manufacturers to significantly lower power consumption on 10GBASE-T server and switch ports. A range of 10GBASE-T switches with 1.5 to 4 W per port are available on the market depending on distance.
However, the SFP+ interface that has been widely deployed for 10 gigabit ToR switches continues to use less power, typically less than 1 W per port. It also offers better latency—typically about 0.3 microseconds per link. 10GBASE-T latency is about 2.6 microseconds per link due to more complex encoding schemes within the equipment.
Featuring lower power consumption and lower latency, SFP+ is well suited for large high-speed supercomputing applications where latency is a critical factor and where high port counts can add up to significant power savings.
The cost of 10GBASE-T technology has been driven down in the past years. And with 10GBASE-T rapidly becoming the de factor LOM technology, the use of SFP+ means an additional cost of adapters for the servers. In comparing one of the latest SFP+ and 10GBASE-T ToR switches, the cost of 10GBASE-T ranges from 20% to 40% less.
10GBASE-T also has the advantage of being an interoperable, standards-based technology that uses the familiar RJ45 connector. It provides backwards compatibility with legacy networks. While SFP+ solutions are limited with little or no backwards compatibility.
10GBASE-T can offer more design flexibility using a structured cabling approach for longer distances up to 100 meters, as well as shorter ToR switch-server connections using category 6A patch cords. A structured cabling approach means that Category 6A cables can be field terminated on patch panels to any length for clean, slack-free cable management. However, SFP+ DAC offers less than 10m distance, and they are factory terminated and must be purchased in pre-determined lengths.
When faced with choosing between SFP+ and 10GBASE-T for 10GbE cabling, carefully consider your needs. If power consumption and lower latency are critical, SFP+ might be the solution for you. If cost, flexibility and scalability are more important, you’ll likely want to consider 10GBASE-T. Regardless of which solution is for you, it’s important to remember that high quality cabling from reputable manufacturers will help ensure performance and reliability—especially since ToR switch-server connections are touched frequently in moves, adds and changes. FS.COM offers both SFP+ Direct Attached Cables for SFP+ and category 6A patch cords for 10GBASE-T—and the experts to help you choose.