[c-nsp] ARP strangeness

[Gert Doering]

Hi,

On Wed, Jan 19, 2011 at 01:47:20AM -0600, Frank Bulk - iName.com wrote:
> You're correct - without broadcast support, re-population initiated from the
> 7609 is impossible.  Once it's expired, the FTTH access gear's design, which
> blocks broadcast traffic, makes it impossible for the CPE to respond to the
> broadcast ARP.  The FTTH access gear never allows broadcast traffic to
> ingress from the 7609.  So the only thing that can re-populate the 7609's
> ARP cache is an ARP request by the CPE, *but* the CPE only does that after a
> DHCP exchange after power on, never again, even after a full DHCP exchange.

This sounds like a very very stupid design in the FTTH gear.

Imagine what happens if the 7609 needs to be rebooted - *all* customers
having to powercycle their CPEs?

(Also, the whole idea of "blocking broadcasts from the ISP side" is
bogus to start with - broadcasts from the CPE side are what needs to
be well-controlled and only distributed to the ISP PE...)

gert
-- 
USENET is *not* the non-clickable part of WWW!
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Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
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