Implementations/suggestions for Multihoming IPv6 for DSL sites

Luigi Iannone luigi at
Tue Apr 19 15:30:58 UTC 2011

On Apr 18, 2011, at 10:09 PM, Owen DeLong wrote:

> On Apr 18, 2011, at 12:18 PM, Jeff Wheeler wrote:
>> 2011/4/18 Lukasz Bromirski <lukasz at>:
>>> LISP scales better, because with introduction of *location*
>>> prefix, you're at the same time (or ideally you would)
>>> withdraw the original aggregate prefix. And as no matter how
>>> you count it, the number of *locations* will be somewhat
>>> limited vs number of *PI* address spaces that everyone wants
>> I strongly disagree with the assumption that the number of
>> locations/sites would remain static.  This is the basic issue that
>> many folks gloss over: dramatically decreasing the barrier-to-entry
>> for multi-homing or provider-independent addressing will, without
>> question, dramatically increase the number of multi-homed or
>> provider-independent sites.
> Done properly, a multi-homed end-site does not need to have
> its own locator ID, but, could, instead, use the locator IDs of
> all directly proximate Transit ASNs.

This is exactly what LISP suggests. Your locators are provided by your provider.


> I don't know if LISP particularly facilitates this, but, I think it
> would be possible generically in a Locator/ID based system.
>> LISP "solves" this problem by using the router's FIB as a
>> macro-flow-cache.  That's good except that a site with a large number
>> of outgoing macro-flows (either because it's a busy site, responding
>> to an external DoS attack, or actually originating a DoS attack from a
>> compromised host) will cripple that site's ITR.
> The closer you move the ITRs to the edge, the less of an issue this becomes.
> Owen

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