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

George Herbert george.herbert at
Fri Nov 1 22:36:25 UTC 2013

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

> * mikal at (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<>
> "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 at

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