SDWAN - Packet Loss Forward Error Correction (FEC)

[Rami Ibrahim]

Hi Guys,

Can anyone clarifies what FEC exactly does?

 In SD-WAN book they said there is a FEC block (consist of four data packets) the router performs Xor operation on them and send the result in 5th packet called parity packet to the receiver, and based on what packets missed by the receiver the sender will be able to reconstructs the lost packet without the need of a transmission.

 So, they mean FEC block is a group of every 4 packets flowing normally in data plane? or special new packets?

 I am a little bit confused.

Thank you.

Romeo,

[ekhabaro]

FEC is just one extra system generated packet containing hash for the group of 4 packets. It is being forwarded in the data plane to gether with data packets as usual.