Re: WCCP - cache only , no proxy

At 15:31 18/04/00, Henrik Nordstrom wrote:
> > while it wouldn't be impossible to do this, and take the hit of maintaining
> > all that per-flow state information in a switching device (can you say:
> > "doesn't scale"?), it would break spectacularly if you had assymetric
> > routing or redundant paths that traffic can take back to the end-user.
>
>So does WCCP, or any other redirection techniques.

actually, no.
there are other products in the marketplace which _do_ masquerade as the
client ip address when talking to web-servers.

i'm merely pointing out that it was a conscious design decision NOT to go
down this path.

>If the traffic flow
>not always passes by the redirection point then you are screwed.

yes.
this is one of the benefits of WCCPv2:
  - you can run a single WCCP service-group on up to 32 routers/switches
    communicating with up to 32 caches.
  - due to the nature on it running in a router/switch, you can typically
    perform the interception, even if traffic is not traversing a
[fast|gigabit]
    ethernet.

>In the long run "transparent" proxying is a dead end. Other means of
>directing the users to the caches must be found. WCCP and other
>redirection techniques should only be seen as a bandaid until these
>other means are found and ready for deployment.

perhaps.
here in the real world, the technique works, has been proven to scale and
is better than the alternatives.

cheers,

lincoln.
NB. i'll take this discussion off-list if you wish, lest this sound too
commercial.

--
   Lincoln Dale           Content Switching
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