Re: [Spud] PCP vs. SPUD

Eliot Lear <lear@cisco.com> Thu, 26 March 2015 19:31 UTC

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Date: Thu, 26 Mar 2015 14:31:15 -0500
From: Eliot Lear <lear@cisco.com>
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To: Aaron Falk <aaron.falk@gmail.com>
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Subject: Re: [Spud] PCP vs. SPUD
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On 3/26/15 2:07 PM, Aaron Falk wrote:
> HI Eliot-
>
> I don't understand your response.  Could you expand on it a little? 
> Are you saying they both solve the problem but SPUD is more efficient?

There are potential efficiency tradeoffs, depending on whether the
results of the work lead to additional packet overhead or not (we cannot
yet say what that tradeoff is).  PCP requires setup but there is no
packet overhead.  The reason that SPUD doesn't require setup is that it
is implicit and observable in the same way TCP is, and the intentions
are clear to everyone.  That has been a good way to protect hosts from
some forms of attack, such as DOS/DDOS.

Eliot