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Re: What price security?

>  Uri Blumenthal writes:
>  > Depends on what you're doing, of course. Five years ago I used 3DES
>  > for telnet, and - surprise - never noticed the speed loss. Now try
>  > real-time video-conferencing and tell me if you notice any 
>  > performance degradation.
>Perry Metzger writes:
>  Remember, 3DES implementations can churn out far higher than ethernet
>  bandwidth data rates on modern processors. In a year or two this will
>  be even less of an issue.
These comments don't mesh for me. you can't both be right. 

If the RT conferencing is being done on the internet-at large, then
end-to-end delay and congestion is going to make it be WELL under an ethernet
in speed and quality. If Perrys comments about 3DES being able to flood
and ethernet is true, then then even for real-time conferencing, 3DES added
delay will be lost in noise for a number of people eg trans-continental or
>15 hop separated parties.

I think the answer is that 3DES can sustain datarate for applications up to
ethernet speed, but delay effects *may* be visible for parties whose normal
end-end delay is under some value which is a crossoverpoint: if the normal
network loading encompasses that delay with sufficient variance, then you
won't notice the difference much, apart from issues relating to loss recovery
for a streaming cipher.

Is that it?

George Michaelson         |  connect.com.au pty/ltd
Email: ggm@connect.com.au |  c/o AAPT,
Phone: +61 7 3834 9976    |  level 8, the Riverside Centre,
  Fax: +61 7 3834 9908    |  123 Eagle St, Brisbane QLD 4000

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