Generally, 10GBASE-T ports with RJ-45 connectors have been adopted by most server NIC (Network Interface Card) and storage appliance units and on the other side of the link, ToR (top-of-rack) switches have SFP+. So when we expand or upgrade our data center networks, what would be the most efficient way to make SFP+ to RJ45 connection? There is no doubt, the answer is a 10G copper SFP solution
What Is SFP+ to RJ45 Connectivity Solution?
The SFP+ to RJ45 solution is to use an SFP+ 10G RJ45 transceiver as an adapter for the SFP+ port and then connect a Cat6/7 cable from the server/storage side to the RJ45 connector of the SFP+ transceiver. It is a much cheaper solution than replacing a new RJ45 to SFP+ switch, and more flexible and less lossy than RJ45 to SFP+ media converters.
4 Factors to Consider When Choosing SFP+ to RJ45 Solution
There are four key points to consider: data rate, categories of twisted-pair cable, latency, and power consumption for data centers.
Data Rates
With continued network expansion and upgrades in data centers from 100BASE-T to 1000BASE-T, 2.5GBASE-T, 5GBASE-T, and 10GBASE-T Ethernet. The 10GBASE-T (IEEE 802.3ae) Ethernet standard is now the most widely used communication standard in data centers. The SFP+ to RJ45 solution provides auto-negotiated backward compatibility with previous generation NBase-T networks for seamless migration to 10GbE.
Categories of Twisted-Pair Cable
Twisted-pair cables consist of two conductors of a single circuit twisted together, which reduce the effects of EMI and mutual interference between pairs and improve electromagnetic compatibility. Nowadays the cables are shielded with aluminum foil to increase protection against crosstalk on neighboring lines. There are Cat5e, Cat6, Cat6a, Cat7, Cat8 Ethernet cables that can be used in your network solution. And this 10Gb copper SFP+ solution can be paired with Cat6a/Cat7 or Better for a transmission distance of 80m.
Latency
We all know that the lower the latency of your network, the better the connected devices can communicate. So latency is critical to network performance. For example, the latency of SFP+ to RJ45 solution is 2.6ms generally. The increase in latency is due to the additional line coding overhead in legacy IEEE 802.3an, where mathematical tasks are being performed to ensure error correction for all packets sent. 2.6 ms per hop is acceptable while keeping the number of hops to a minimum.
Power Consumption
For data center network professionals, the power consumption of active devices is very important. After all, every watt consumed by a device means that two additional watts are needed to cool the data center. Take 3Coptics SFP+ copper solution as an example, its power consumption is 2.5W or less, and the longer the length, the lower the power consumption of the 10GBase-T modules.
SFP+ to RJ45 Solution: Pros and Cons
Pros
Support backward compatibility with the adoption of common RJ45 connectors and network expansion for a lower cost.
A more cost-effective solution than replacing 10G SFP+ switches with 10GBASE-T RJ45 switches; A stabler solution than 10G SFP+ to RJ45 media converters.
Support multiple data rates and is easy to operate and manage.
Cons
Higher power consumption compared to optical connections (especially when multiple units are used in the switch).
Increased heat compared to optical connections (when using multiple units in the switch).
Increased latency (especially when connecting multiple jump points).
