RT info:eu-repo/semantics/article T1 Improving multipath routing of TCP flows by network exploration A1 Álvarez Horcajo, Joaquín A1 López Pajares, Diego A1 Martinez Yelmo, Isaias A1 Carral Pelayo, Juan Antonio A1 Arco Rodríguez, José Manuel K1 Data networks K1 ECMP K1 Ethernet K1 Flow completion time K1 Load balance K1 Multipath K1 Network exploration K1 Throughput K1 TCP K1 Informática K1 Computer science AB Ethernet switched networks are widely used in enterprise and data center networks. However, they have some drawbacks, mainly that, to prevent loops, they cannot take advantage of multipath topologies to balance traffic. Several multipath routing proposals use link-state protocols and Equal Cost Multi-Path routing (ECMP) to distribute the load over multiple paths. But, these proposals are complex and prone to flow collisions that may degrade performance. This paper studies TCP-Path, a protocol that employs a different approach. It uses a distributed network exploration mechanism based on broadcasting the TCPSYN packet to identify and select the fastest available path to the destination host, on the fly. Our evaluation shows that it improves on ECMP by up to 70% in terms of throughput for elephant flows and by up to 60% in terms of flow completion time for mouse flows. Indeed, network exploration offers a better, yet simple alternative to ECMP-based solutions for multipath topologies. In addition, we also study TCP-Path for elephant flows (TFE), which restricts TCP-Path application to elephant flows to reduce the exploration broadcast overhead and the size of forwarding tables, thus improving its scalability. Although elephant flows represent a small fraction (about 5%) of total flows, they have a major impact on overall performance, as we show in our evaluation. TFE reduces both the overhead incurred during path setup and the size of the forwarding tables by a factor of almost 20. Moreover, it achieves results close to those obtained by TCPPath for elephant flows, especially when working with high loads, and yields significant improvements for all types of flow at medium and high load levels. PB IEEE SN 2169-3536 YR 2019 FD 2019-01-18 LK http://hdl.handle.net/10017/48087 UL http://hdl.handle.net/10017/48087 LA eng NO Comunidad de Madrid DS MINDS@UW RD 29-mar-2024