DES-ECB Encryption Strength

Attack Method	Known	Chosen	Storage Factor	Work Factor
Exhaustive precomputation	--	1	2^{^56}	1 (table lookup)
Exhaustive search	1	--	Negligible	2^{^55}
Linear cryptanalysis	2^{^43} (85%)	--	For texts	2^{^43}
Linear cryptanalysis	2^{^43} (10%)	--	For texts	2^{^50}
Differential cryptanalysis	--	2^{^47}	For texts	2^{^47}
Differential cryptanalysis	2^{^55}	--	For texts	2^{^55}

Ref: ICSA Guide to Cryptography, 1999; p. 210

Threat	Budget	Technology	Time to break 40-bit DES	Time to break 56-bit DES
Hacker	Tiny	Scavenged time	1 week	Infeasible
Small Business	$10K	FPGA	12 min	556 days
Corporation	$300K	FPGA or ASIC	24 sec	19 days
Big Corporation	$10M	FPGA or ASIC	.7sec	13 hours
Government	$300M	ASIC	.0002 sec	12 sec

FPGA = Field Programmable Gate Array
ASIC = Application Specific Circuits

Ref: ICSA Guide to Cryptography, 1999; p. 211

My Comments: I have yet to find any information that DES-CBC (with IV) has been breakable yet. There are still many government and financial organizations using this Encryption method and they will probably continue to do so until Triple DES has been proven safer. At present, government specifications state that equipment supporting Triple DES should be purchased so that whenever it is deemed stable, new equipment will not have to be purchased.

For those of you interested in knowing the differences between DES-EBC and DES-CBC (with IV), I suggest you purchase the book "ICSA Guide to Cryptography" albiet a little out-dated or newer published Encryption material. As DES-EBC and CBC (with IV) have been around for some time, the book does not have to be that up-to-date to find the differences.

If you think about it, anybody who is willing to pay $300,000 to $10,000,000 probably can find a quicker and cheaper way to get that information via other means.

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