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Harald Koenig koenig@tat.physik.uni-tuebingen.de
Thu Jul 22 05:58:03 1999


On Jul 22, Peter Black wrote:

> 	Scp has to encrypt (and conpress depending if you asked it to) the file
> before sending it down the line. Although the time spent to encrypt the
> data should be minimal as compared to compression.

using a K6/2-400 with ssh-1.2.26 and ~50+ MByte gziped data from buffer cache 
I get the following transfer rates:

				sec / ~50MB	MB / sec

	rsh			  3.87		13.56

	ssh -c none		  8.55 		 6.14
	ssh -c arcfour		 17.12		 3.06
	ssh -c blowfish		 21.25		 2.47
	ssh -c idea (default)	 38.02		 1.38
	ssh -c des		 37.46 		 1.40
	ssh -c 3des		 91.14		 0.57

	ssh -C -c none		 64.16 		 0.82

as you can see, compression doesn't take much more time than encryption
with e.g. IDEA (default) or DES, and 3DES even is quite slower.


Harald
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