> In summary, the draft amends RFC 2461 to allow at most one router on
> a link to reply immediately to an RS instead of waiting a random
> amount of time between 0 and MAX_RA_DELAY_TIME. The router is
> allowed to reply to at most MAX_FAST_RAS since the last unsolicited
> multicast is sent. If this number is exceeded, the router rolls over
> to scheduling a multicast RA as soon as possible. This is intended
> to avoid DoS attacks on the router.

This presumably requires some per-link or per-router configuration?
I.e., how does the "one" router that is allowed respond more quickly
get picked? Given that, putting the words in a standards track doc
seems with regards to how a collection of routers behaves seems a bit
odd. I see that this document just says how this is configured is out
of scope for the document....

Stepping back for a minute. MAX_RA_DELAY_TIME is .5 seconds. A router
delays a random amount of time between 0 and .5 seconds before
responding. So, on average, .25 seconds. That's not a terribly long
delay. What exactly is the application that  can't deal with this kind
of a delay?

Then there is more to getting link connectivity than just finding a
router. You may have to generate an address, and then invoke DAD.  But
DAD (on an Ethernet) requires a 1 second delay. That's a much bigger
factor than the RS delay. Is this not also an issue?  I.e., what is so
critical about getting an immediate RS but that doesn't also have an
issue with some of the other ND/addrconf/DAD constants. Will
addressing the RS delay alone *really* solve the problem here, and if
not, shouldn't we be thinking about the more general problem and
working on finding a solution that deals with all the potential delay
spots?

Thomas
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