Low-latency applications drive an increasing number of modern applications. Latency depends on factors such as link layer technologies and how higher-layer protocols cope with transmission errors and packet losses. Most transport protocols rely exclusively on retransmissions to cope with losses with minimal overhead but potentially large tail latency. This paper leverages network coding to propose the high-speed robust tunnel (HIRT), providing timely packet delivery to any application independently of the transport protocol. A network code recovers lost data without requiring time-consuming retransmissions by adding redundancy packets, thereby slightly increasing the bandwidth usage to reduce the tail latency. Our algorithm dynamically adapts the rate of redundancy packets by measuring the network loss patterns. We implement HIRT using IPv6 Segment Routing (SRv6). We suggest an efficient software implementation and demonstrate on CloudLab that our solution can protect traffic at high speeds ($>50 \text{Gbps}$) on standard servers even when facing severe packet losses in the network. We evaluate HIRT with HTTP over TCP/QUIC, and file system benchmarks over a real network with losses, Starlink. HIRT reduces the tail latency of short HTTP requests by$2 \times$and the mean request completion time of longer requests by up to$20 \%$. HIRT also decreases the tail latency of NFS requests by up to$20 \%$.

Researchers often face the lack of data on large operational networks to understand how they are used, how they behave, and sometimes how they fail. This data is crucial to drive the evolution of Internet protocols and develop techniques such as traffic engineering, DDoS detection and mitigation. Companies that have access to measurements from operational networks and services leverage this data to improve the availability, speed, and resilience of their Internet services. Unfortunately, the availability of large datasets, especially collected regularly over a long period of time, is a daunting task that remains scarce in the literature.

The Transmission Control Protocol (TCP) is one of the key Internet protocols. It is used by a broad range of applications. TCP was designed when there was typically a single path between a client and a server. Today’s networks provide higher path diversity, yet TCP still only uses the single path selected by the network layer. This limits the ability of TCP to react to events such as interdomain failures or highly congested peering links. We propose the TCP Path Changer (TPC), a set of eBPF programs that are incorporated into the Linux TCP/IP stack to make it more agile. To illustrate the benefits of our approach, we first demonstrate that TPC can quickly reroute an ongoing TCP connection around a failure. We then show that TPC can also monitor the round-trip-time of active TCP connections and automatically reroute them if it becomes too high. Our evaluation of TPC in emulated networks evidences the significant performance benefits of a path-aware transport protocol.