TCP's slow start phase is particularly inefficient over most wireless networks, especially high-latency, high-bandwidth paths such as satellite networks, often exiting too early or too late (after packet loss). To address this, the Slow start Exit At CHokepoint (SEARCH) algorithm is designed to improve exit decisions during slow start by analyzing delivery trends across sliding RTT-based windows. This paper presents a first implementation of SEARCH in the FreeBSD kernel using FreeBSD's modular congestion control framework. We evaluate our implementation on a testbed with an actual GEO satellite link with \textasciitilde 600 ms RTT and 150 Mb/s capacity. Preliminary results show that SEARCH exits slow start more effectively than HyStart and HyStart++, achieving higher throughput and better utilization.

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• Maryam Ataei Kachooei, Joshua Chung, Amber Cronin, Benjamin Peters, Feng Li, Jae Won Chung, and Mark Claypool. Implementation of the SEARCH Slow Start Algorithm in the Linux Kernel, In Proceedings of the 0x18 NetDev Conference, Santa Clara, California, USA, July 2024. Online at: http://www.cs.wpi.edu/~claypool/papers/search-netdev-24/

• Maryam Ataei Kachooei, Jae Chung, Feng Li, Benjamin Peters, Josh Chung, and Mark Claypool. Improving TCP Slow Start Performance in Wireless Networks with SEARCH, In Proceedings of the IEEE World of Wireless, Mobile and Multimedia Networks (WoWMoM), Perth, Australia, June 2024. Online at: https://web.cs.wpi.edu/~claypool/papers/search-wowmom-24/

• Amber Cronin, Maryam Ataei Kachooei, Jae Chung, Feng Li, Benjamin Peters, and Mark Claypool. Improving QUIC Slow Start Behavior in Wireless Networks with SEARCH, In Proceedings of the IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN), Boston, MA, USA, July 2024. Online at: https://web.cs.wpi.edu/~claypool/papers/quic-search-lanman-24/

• Maryam Ataei Kachooei, Jae Chung, Feng Li, Benjamin Peters, and Mark Claypool. SEARCH: Robust TCP Slow Start Performance over Satellite Networks, In Proceedings of the 48th IEEE Conference on Local Computer Networks (LCN), Daytona Beach, FL, USA, October 1-5, 2023. Online at: https://web.cs.wpi.edu/~claypool/papers/search-lcn-23/

• Maryam Ataei Kachooei, Pinhan Zhao, Feng Li, Jae Won Chung, and Mark Claypool. Fixing TCP Slow Start for Slow Fat Links, In Proceedings of the 0x16 NetDev Conference, Lisbon, Portugal, October 2022. Online at: http://www.cs.wpi.edu/~claypool/papers/tcp-best-netdev-22/

• Benjamin Peters, Pinhan Zhao, Jae Won Chung, and Mark Claypool. TCP HyStart Performance over a Satellite Network, In Proceedings of the 0x15 NetDev Conference, Virtual Conference, July 2021. Online at: http://www.cs.wpi.edu/~claypool/papers/tcp-hystart-netdev-21/