400GE – Not Just More and Faster, FEC’n Different
One of the first popular industrial bands, a German group called KMFDM, saw some traction with the catchy tune, “More and Faster” – in the late 80’s. While probably not their intent and regardless of what you might think of Teutonic industrial bands, “More and Faster” captured the story of the evolution of Ethernet for most of its history. It wasn’t about fundamental change, it was about speeds and feeds.
This changed with the advent of 200GE and 400GE where physics has started to rear its ugly head. Not the first time that the industry has faced such challenges, with Moore’s Law being declared dead a number of times. In this case the extreme speeds of the 400GE electrical interfaces result in a fundamentally noisy environment with the best way out being to introduce error correction, in this case FEC.
FEC, or Forward Error Correction, is a way of sending error free communications over noisy or unreliable channels. This is done by including redundancy in the message itself in the form of ECC – Error Correcting Code. While this increases the overall size of the message, it reduces or eliminates the need for re-transmits and leaves us in a better position overall with regards to speed, performance and accuracy.
Want to get a better grasp of the inner workings of FEC in 400GE? Grab our free poster! Want to learn even more? We have a white paper on 400 GE including FEC and Other Good Stuff.