Twinax cable is a type of cable similar to coaxial cable. The difference is that there are two inner conductors other than on in coaxial cable. This kind of cable is commonly used for very short range high speed differential signaling applications. There are basically two types of twinax cable for 10G Ethernet: SFP+ active and SFP+ passive twinac cable.
Currently there is a copper 10 Gigabit Ethernet cables which comes in either an active or passive Twinax cable assembly and connects directly into an SFP+ housing. SFP+ cable is a twinax cable with SFP+ connector at each end. An active twinax cable has active electronic components in the SFP+ housing to improve the 10 Gig Ethernet signals quality. A SFP+ passive twinax cable is just a direct attach cable and contains no active components to boost signal.
SFP+ Passive Direct Attach Twinax cable is suitable for very short distances. They are rated for a range up to 5m and provide a good working solution at a great cost. When the distance between connection points exceed 5m. It is highly recommended to use active cable to ensure signals are transmit all the way through. 5m as the boundary is not absolute, as it may vary from vendor to vendor. For example, FS.COM 10G SFP+ passive twinax cable can be the optimum solution for 10G Ethernet reaches up to 12M.
Except the transmission length, there is indeed no visual difference between SFP+ active and passive twinax copper cable. SFP+ connectors are the same and the cable jackets are also identical. Most manufactures including FS.COM will have some sort of marking on the cable connector head which will identify the cable as active or passive. But it is also not simply to tell by just looking at it.
The major applications of SFP+ twinax cable are working with network hardware with SFP+ slot. FS.COM SFP+ cables can be compatible with major brands such as Cisco, HPL, Juniper, Extreme, H3C etc. This type of connection is able to transmit at 10 Gigabit/second full duplex speeds over 12 meter distances. What’s more, this setup also offers 15 to 25 times lower transceiver latency than current 10GBASE-T Cat6/CAT6a/Cat7 cabling systems.