I have to build a 5GbE link with a SFP+. Can i use the one that is rated for 8Gbps? And what kind of NIC should I use on host PC?

1 Answer 1


Both 5 Gbps and 8 Gbps are non-standard ethernet speeds, and you won't find those speeds on SFP+s. In fact, you will not find 8 Gbps ethernet at all. If you are using fiber, you will get 10 Gbps, but you must make sure of the fiber and length, which must match the SPF+, which must also match the SFP+ on the other end. Some copper SFP+s can also do 1 Gbps (possibly 100 Mbps and 10 Mbps), besides 10 Gbps.

Some switches from members of the NBASE-T Alliance have ports which can do 2.5 or 5 Gbps, besides the standard 10 or 100 Mbps, and 1 or 10 Gbps.

It is unlikely that you will find a host NIC that can do either 5 or 8 Gbps. There are server NICs which can do 10 Gbps.

  • That's bad news... So i will need a switch to get 5GbE and the 10GbE link to the host? Jun 18, 2016 at 8:04
  • If you need 5 Gbps, then you should just get 10 Gbps gear. That will let you run up to 10 Gbps. I don't understand the need to limit it to 5 Gbps. You could always do policing to limit a 10 Gbps connection to 5 Gbps.
    – Ron Maupin
    Jun 18, 2016 at 8:06
  • I have hardware with 6.6Gbps transceivers. Going to 10Gbps costs to much for the system and requires development cycle that i am not sure i can afford. Jun 18, 2016 at 8:08
  • There are no ethernet 6.6 Gbps transceivers. You have something else.
    – Ron Maupin
    Jun 18, 2016 at 8:08
  • It's a generic transceiver. I use Zynq7030. It can be configured to ethernet or anything else. Jun 18, 2016 at 8:10

Not the answer you're looking for? Browse other questions tagged or ask your own question.