Re: [tlug] Unix's 40th Birthday

[Curt Sampson <cjs@example.com>]

On 2009-08-21 11:38 +0900 (Fri), Edward Middleton wrote:

> Curt Sampson wrote:
> > Edward Middleton wrote:
> >   
> > ... I see nothing on their web site that indicates they don't take a
> > conventional approach, and considerable evidence that they do...
> >
> > Their EOS may be based on Linux, but it sounds as if it's a mere control
> > system for the hardware and software that does the real work.
> 
> Well I guess it depends what you call a conventional approach.

What they are doing is exactly the conventional approach to this, vis:

> Processing is in user space.  Protocol operation, management function,
> and device management, including hardware device drivers, run in user
> address space.
> 1. http://www.aristanetworks.com/en/EOSWhitepaper.pdf

Note that this is exactly what Cisco achieved when they put QNX underneath
IOS (see http://en.wikipedia.org/wiki/Cisco_IOS#Architecture). In fact, it
appears that EOS could just as easily be based on QNX (or any other POSIX
OS) as Linux.

So my main point here was that it's rather bogus to claim that Linux
has much to do with moving packets around when the packets never get
near the kernel TCP/IP stack (if this kernel even has one!), the kernel
routing table knows nothing about the routing table the router is using
(again, if the kernel even has a routing table), kernel device drivers
never touch the hardware, and all the work is done by programs running
in userland that are written by someone else.

You might as well say that, because I used a Linux box to telnet into my
Cisco to configure it, Linux is "running my network."

cjs
-- 
Curt Sampson       <cjs@example.com>        +81 90 7737 2974
           Functional programming in all senses of the word:
                   http://www.starling-software.com