Network Stack Code Re-write (Possible motivations...?)

[RW]

On Sat, 20 Dec 2008 13:35:35 -0500
Martes G Wigglesworth <martes at mgwigglesworth.com> wrote:


> However, the intuitive list member response strikes again.
> 
> Thanks alot for you input.
> 
> I, as you, can't really figure out why they felt, years ago, that they
> needed to re-invent the wheel.


Bear in mind that such companies may have a range of products, that
range from something not unlike a pc with lots of interfaces up to
something with multiple levels of embedded processors each running their
own OSes. In the latter case you need a network stack that's
largely OS independent, so it can spread itself across the
(non-symmetric) processors. You may also need to be able to separate
fast-path, slow-path and control path for high performance.

Once you have done all that, you've left the native OS stacks unused,
leaving them available for the user interface or in some cases
communication between sub-systems. This separation is good on security
grounds too, it's preferable not to have network management "in-band".