Minimizing latency and maximizing reliability of internet connections is an increasingly important feature for modern interactive applications. This applies especially to streaming services and remote control applications where reliable real-time response is essential.

As of today almost all transport protocols utilize the same mechanisms for offering reliable connectivity namely ARQ (retransmissions). While bandwidth optimal ARQ sacrifices latency in order to provide the ARQ mechanism enough time to fix any occurring packet loss.

As an alternative to ARQ, protocols can utilize a technique called ECC (Erasure Correcting Codes). Using ECC protocols can generate repair packets capable of recovering lost packets - reducing or eliminating the need for ARQ. While ECC can operate at the lowest possible latency the cost in this case is bandwidth. For ECC to work the amount of repair packets must exceed the amount of lost packets - since this can be hard to accurately predict often times a large safety margin has to be added. In effect causing a substantial increase in the bandwidth consumption.

The basic goal of Raft (reliable adaptive FEC transport) is to utilize the properties of ECC (Erasure Correcting Codes) to offer a solution where the combination of ECC and ARQ enables reliable communication without exceeding the latency requirements of the application while minimizing the bandwidth needed to handle packet loss.