TCP westwood

[Lawrence Stewart]

Hi Jerry,

On 02/01/10 09:49, Jerry Toung wrote:
> Hello list,
> my employer is asking me to implement westwood, this is most likely happen
> on 8.0.
>
> before I start, I'd like to know for what reason it hasn't been done in the
> main tree?
> is it that no one has had time, or it only work in a lab environment? may be
> too many changes in the stack
> and it's not trivial? etc...

IMHO, lack of a really compelling reason is a good start. Changing the 
TCP stack is fiddly and error prone work.

> Does any one out there has patch they can share?

I haven't come across a BSD licenced implementation in my travels, 
although FreeBSD already does a few different types of bandwidth 
estimation and limiting (which, in their current form at least, I'm 
personally not a fan of).

> would the project be interested in a patch if I do this?

I'm interested in and actively working on this area in FreeBSD. I 
already have a patch available that adds modular congestion control 
support to FreeBSD's TCP stack which would be a good starting point for 
you. I would also be supportive of importing a Westwood congestion 
control module into FreeBSD after you complete it.

Have a look at the project branches here:
http://svn.freebsd.org/base/projects/tcp_cc_{7.x,8.x,head}

Happy to discuss further when you're ready.

Cheers,
Lawrence