  Over the past years, TCP has gone through numerous updates to provide
performance enhancement under diverse network conditions. However, with respect
to losses, little can be achieved with legacy TCP detection and recovery
mechanisms. Both fast retransmission and retransmission timeout take at least
one extra round trip time to perform, and this might significantly impact
performance of latency-sensitive applications, especially in lossy or high
delay networks. While forward error correction (FEC) is not a new initiative in
this direction, the majority of the approaches consider FEC inside the
application. In this paper, we design and implement a framework, where FEC is
integrated within TCP. Our main goal with this design choice is to enable
latency sensitive applications over TCP in high delay and lossy networks, but
remaining application agnostic. We further incorporate this design into
multipath TCP (MPTCP), where we focus particularly on heterogeneous settings,
considering the fact that TCP recovery mechanisms further escalate head-of-line
blocking in multipath. We evaluate the performance of the proposed framework
and show that such a framework can bring significant benefits compared to
legacy TCP and MPTCP for latency-sensitive real application traffic, such as
video streaming and web services.
