SFP+ DAC Cable

- Nov 11, 2019-

10G SFP+ DAC cable 

SFP (Small form-factor Pluggables) is an updated version of GBIC(Gigabit Interface Converter). Its volume is reduced by half compared with GBIC module, and its function is basically consistent with GBIC, realizing the function of converting Gigabit electrical signal into optical signal. The 10G module experienced the development from 300Pin, XENPAK, X2 and XFP, and finally realized the transmission of 10G signal with the same size as SFP, which is SFP+. SFP+, with its advantages of miniaturization and low cost, met the equipment's demand for high-density optical modules. Since the standard was introduced in 2002, it has replaced XFP and become the mainstream of 10G market in 2010. SFP is regulated by the protocol MSA jointly formulated by many manufacturers, and the protocol followed by SFP+ is IEEE 802.3ae, sff-8431 and sff-8432.




For card interconnection between cable components (including interface module on both ends) called Direct connection cable-Direct Attach Cables (DAC). DAC cable assembly is mainly used in 10 g Ethernet switch stack connection, TOR interconnection switch and server, fibre channel device interconnection, InfiniBand equipment interconnection and interconnection between the server/storage devices.

SFP+ DAC is also known as 10GSFP+ copper, 10gbase-cr or SFP+, 10gbase-cx1, or 10GbE copper SFP cable. Direct connection, using passive biaxial cable assemblies, and direct connection to the SFP+ module. SFP+ direct connection has a fixed length cable, usually 3,5 or 7 meters in length, using small size cable and small size SFP+ module, with the advantages of low power, low cost and low delay.

SFP+ DAC direct connection cable

In the past, server manufacturers were basically free to use the built-in RJ45 port on the motherboard. Now 10G ports are expensive, and pluggable port modules are a significant cost barrier. Currently, there are three kinds of 10G Ethernet data center mainstream server network CARDS: 10G base-cr SFP+ network CARDS. This optical network card needs to be connected with 10G SFP+ DAC(Direct Attach Cable). There are also 10G base-t copper network CARDS and 10G base-sr optical network CARDS. According to the current state of technology development, compared with the overall cost and power consumption, the cost of optical link is about 1.3 times of that of copper link. The 10gbase-t copper network card USES the RJ45 interface. Currently, the mass sold network CARDS on the market have relatively high power consumption. At present, many users are still waiting and waiting, expecting that the power of 10G base-t can be greatly reduced.

The new trend of data center architecture is mentioned in the appendix of tia942-a-1 draft standard, which is compatible with the more flat large-layer network architecture (Fabric). Traditional HDA has and EDA integration, USES the TOR architecture is one of the direction of the virtual data center, access layer switches are placed on each cabinet above, reduce wiring between each cabinet and column head ark, but each rack server density increased, the server and the increased Numbers of the interconnect access switches, distance shortened, delay also greatly narrowed, under this architecture, 10 g SFP + DAC direct way to reflect the advantage of cost and low power consumption, and for passive DAC straight wire 7 meters distance limit would no longer be a problem.