"Packet Shapers"

Lincoln Dale ltd at interlink.com.au
Fri Jul 31 12:25:10 UTC 1998

In message <005501bdbc4f$2e8665c0$0540d6d1 at oreo.eng.bellsouth.net>, "Christian Kuhtz" writes:
>> shaper->router?  Now add in a transparent proxy.  Ugh.  Look for a
>> vendor that will include a transparent proxy capability in their box.  I
>The methods discussed so far are certainly not scalable for large service
>providers.  Btw: DS-3, IMHO, does not count as real true broadband.  T1's

i guess its a matter of where you deploy them within your network.

certainly, i wouldn't see deployment of transparent proxy boxes in the middle
of a large backbone working particularly well -- both in terms of scaling
issues, but perhaps more as a political issue

(as recently shown by the testostorone-charged-thread in this list not-so-
long-ago when digex put a netapp netcache transparently on some customers --
presumably via some vendors' L4 switch).

where they _do_ win, however, is at the access-router-edge of your network.

there are currently things that some vendors' boxes can do, that can't be
done (yet) in IOS.  .. and for some of them, they are scaling beyond a
DS3 already.

for one vendor's gear (alteon), for transparent proxying, i took it up to
2 x DS3's without it skipping a beat.  i stopped there, as it is academic
in this country (australia) to be going beyond that, for a pool of dialup
customers of the largest dialup isp and the only cablemodem offering.

i guess the point being that limitations were hit in the actual proxy-cache-
boxes well before limitations were hit in layer-4 switch functionality.
(biggest factor being: (total-transaction-time x trans-per-sec) > max-fd's).



(nb, yes, cisco do have WCCP - however, with it effectively being a
proprietary protocol, and whilst some of the functionality is possible in
policy-based-routing, you lose out big time when your cache isn't functioning
and the router is still (blindly) feeding it all the http-flows).

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