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Re: latest Snowden docs show NSA intercepts all Google and Yahoo DC-to-DC traffic


From: George Herbert <george.herbert () gmail com>
Date: Fri, 1 Nov 2013 15:36:25 -0700

On Fri, Nov 1, 2013 at 3:26 PM, Niels Bakker <niels=nanog () bakker net> wrote:

* mikal () stillhq com (Michael Still) [Fri 01 Nov 2013, 05:27 CET]:

 Its about the CPU cost of the crypto. I was once told the number of CPUs
required to do SSL on web search (which I have now forgotten) and it was a
bigger number than you'd expect -- certainly hundreds.


False: 
https://www.imperialviolet.**org/2010/06/25/overclocking-**ssl.html<https://www.imperialviolet.org/2010/06/25/overclocking-ssl.html>

"On our production frontend machines, SSL/TLS accounts for less than 1% of
the CPU load, less than 10KB of memory per connection and less than 2% of
network overhead. Many people believe that SSL takes a lot of CPU time and
we hope the above numbers (public for the first time) will help to dispel
that."


That was *front end* SSL/TLS - not internal / back end SSL/TLS.

One could assert that the per-activity SSL/TLS overhead might be the same
for internal services accessed to answer a front-end request, but that's
not necessarily true.  The code/request ratios and external/internal
SSL/TLS startup costs are going to vary wildly from service to service.


-- 
-george william herbert
george.herbert () gmail com


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