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Earlier versions of Fedora has different loadable kernel modules which includes diffrent congestion control algorithms etc at (/lib/modules/"kernel-name"/kernel/ipv4).These are present in the form of .ko files like tcp_veno.ko , tcp_westwood.ko . But when i started using fedora 17 i found out that these modules are not present at the given location and i want to use different congestion control algorithms.Please suggest me a way for using those algorithms in fedora 17. ??

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edit: It appears you need to install the kernel-modules-extra package, which contains the congestion control algorithms.

Leaving the rest, which applies in general, regardless of distro:

They may be built-in, instead of compiled as modules. You can check which congestion control algorithms your kernel knows about:

$ cat /proc/sys/net/ipv4/tcp_available_congestion_control 
cubic reno

There is also tcp_allowed_congestion_control (which ones non-privileged processes are allowed to request) and tcp_congestion_control (the default). Documentation is in ip-sysctl.txt.

If Fedora has not built them, you'll need to build a custom kernel.

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You are the hero that SE needs, but not the one that it deserves. – Bratchley Mar 26 '13 at 20:24
Doesn't seem to be the case. I had already kernel-modules and kernel-modules-extra installed, but even though the /boot/config-* reports that most TCP congestion algo are compiled as a module, only tcp_dctcp is available as a module. So I can only choose between cubic, reno (kernel builtin) and dctcp (after loading the module). Other algorithms are unavailable... – Huygens Sep 16 '15 at 20:28

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