QSFP+ Cable—Is It Much Better Than SFP+ Cable?
QSFP+ (Quad Small Form-Factor Pluggable) is an extension of the established I/O interface system SFP+ and was developed for 40 Gb/s Ethernet and 40 Gb/s Infiniband QDR applications. There are QSFP+ cable and SFP+ cable according to these two modules. People might wonder that whether QSFP+ cable is better than SFP+ cable? This passage will provide you a clear answer.
First, the QSFP+ cable is specified for use with the 40GBASE-CR4/SR4, can be copper direct attached cable (DAC) or optical module, while SFP cable with SFP+ connector, is designed to work with equipment with 10G SFP+ interface. QSFP+ cable is obviously four times faster than SFP+ cable in transmission speed as 40G QSFP+ cable is the full duplex 4 channel 850nm parallel active optical cable and its transmission data rate is up to 10.3Gbit/s per channel. The 40G QSFP+ cable is widely used in 40G Ethernet, QDR InfiniBand and data center.
Then, as the 40G QSFP+ cable features QSFP+ connectors on both ends, eliminating the need for expensive QSFP+ transceiver. 40G QSFP+ cable is more cost-effective compared with 10G SFP cable, which is more economical for customers. Taking QSFP+ AOC and SFP+ AOC as an example, QSFP+ AOC is an assembly of 4 full-duplex lanes, where each lane is capable of transmitting data at rates up to 10Gb/s, providing an aggregated rate of 40Gb/s. However, the SFP+ AOC delivers a single bi-directional channel operating at up to 10.3125 Gbps while using a subtle 240mW (typical) of energy per end and the average prize is nearly 20 dollars.
Last but not least, we all know that 40G QSFP+ cables and 10G SFP+ cables are the two main DAC cables on the market. 40G QSFP+ cable is designed for high-density applications that integrate 4 InfiniBand channels at 10 Gbps per lane in order to maximize performance. 40G QSFP+ Cable assemblies are high speed, low latency, twinaxial copper cables. The cable offers a highly cost-effective way to establish a 40-Gigabit link between QSFP+ ports of QSFP+ switches within racks and across adjacent racks. Yet the 10G SFP+ cables provide high performance in 10 Gigabit Ethernet network applications, using an enhanced SFP+ connector to send 10Gbps data through one paired transmitters and receivers over a thin twinax cable. Therefore 40G QSFP+ cable is advanced and more suitable for the fast-developed technology.
In a word, 40G QSFP+ cable is high speed, low latency, twinaxial copper cable used for high speed network backbones, enterprise network switching and network storage. This makes it an optimal solution for handling high bandwidth transmission within short distances such as within a rack or between racks inside energy-efficient data centers while 10G SFP+ can’t reach that.