Ethernet Cables Primer Overview
Ethernet in today’s data centers consists of a family of multilane link types with various signal rates per lane (Table 3).
Table 3. Ethernet speeds
Name |
Lanes |
Signaling Rate per Lane (Gbps) |
Effective Bandwidth (Gbps) |
Connector |
Deployed |
|---|---|---|---|---|---|
GbE |
1 |
1 |
1 |
SFP, RJ45 |
|
10 GbE |
1 |
10 |
10 |
SFP+ |
2002 |
25 GbE |
1 |
25 |
25 |
SFP28 |
2016 |
40 GbE |
4 |
10 |
40 |
QSFP |
2010 |
50 GbE |
2 |
25 |
50 |
QSFP28 |
2016 |
50 GbE |
1 |
50 |
50 |
QSFP56 |
2016 |
100 GbE |
4 |
25 |
100 |
QSFP28 |
2010 |
200 GbE |
4 |
50 |
200 |
QSFP56 |
2018 |
Ethernet support of single-lane links provides a wider range of speeds than InfiniBand:
There are two versions of 50 GbE: a single lane at 50 Gbps, and dual lanes at 25 Gbps. This document will refer to the latter as “50 GbE (2x25).”
There are two versions of 100 GbE: using four lanes at 25 Gbps, and dual lanes of 50 Gbps; the latter will be referred to as “100 GbE (2x50).”