Soft Real-Time Applications with Varying Bit Rates (VBR)

In this section we present the results of our MPEG video analysis. The following tables give the % overhead that decryption introduces in a MPEG video application as compared to MPEG decoding.

PSYCHO

Machine	Decoding Time	Decryption Time	Overhead
	(TD Secs)	(TE Secs)	%
UltraSparc	44.55	1.89	3.81
Pentium III	39.72	1.61	4.06
PentiumPro	61.0	3.59	5.88

WALL

Machine	Decoding Time	Decryption Time	Overhead
	(TD Secs)	(TE Secs)	%
UltraSparc	17.23	0.51	2.97
Pentium III	13.68	0.45	3.29
PentiumPro	27.32	1.04	3.80

HIGHLANDER

Machine	Decoding Time	Decryption Time	Overhead
	(TD Secs)	(TE Secs)	%
UltraSparc	12.38	0.64	5.19
Pentium III	9.49	0.56	5.85
PentiumPro	19.97	1.27	6.36

From the above set of tables we can see that decryption adds an overhead of roughly 3-7% to MPEG decoding. This indicates that encryption can be easily incorporated into a MPEG video application at acceptable overheads.