Refer:
TCP congestion control – Wiki ↗
Linux Kernel – IPv4 Stack /net/ipv4 ↗
TCP CUBIC: Binary Increase Congestion control for TCP – /net/ipv4/tcp_cubic.c ↗
TCP-HYBLA Congestion control algorithm – /net/ipv4/tcp_hybla.c ↗
TCP Illinois congestion control – /net/ipv4/tcp_illinois.c ↗
TCP Westwood+: end-to-end bandwidth estimation for TCP – /net/ipv4/tcp_westwood.c ↗
TCP Vegas congestion control – /net/ipv4/tcp_vegas.c ↗
TCP Veno congestion control – /net/ipv4/tcp_veno.c ↗
H-TCP congestion control: TCP for high-speed and long-distance networks – /net/ipv4/tcp_htcp.c ↗
Also refer the Kernel Architecture difference between a standard Linux System vs Android OS, discussed in this video: