PKZIP (PKWARE)

How to set up and use PKZIP for secure data transmission

Once you’ve downloaded PKZIP from PKWARE (www.pkware.com) and installed it on your PC, set it up as follows:

Tools > Options > Security (icon) > Encryption (tab) >

●     Select Encrypt files (checkbox)

●     Method: select Strong: Password

●     Algorithm: select AES (256-bit)

●     Set Min password length to 16 or greater

       (the number represents the quantity of characters for the password)

You can now send highly confidential files over the Internet.

The best thing to do for lengthy passwords is to use a paraphrase. Here is an example of a paraphrase.

This paraphrase has more than 48 symbols (characters), yet it is very easy to remember:

The little red ridding hood got out of the woods

See if some hacker can figure this one out – this one has 48 symbols out of a 52 different symbols set (lower and uppercase Latin letters); in other words, 52⁴⁸ possible combinations. The time required to decode this password is 2.334 x 10⁸² years - at a rate of 1 million passwords per second.

How can I estimate how much time it would take to use brute-force to crack passwords of a certain length?

Quite simply, knowing the set of symbols used in making the password (if you take only lower-case Latin letters - then 26, if digits, too - then 36 - see the table below), raise that number to the power of the password length and you will get the number of all possible variants for brute-force. Then you should divide this number by the brute-force rate. If you use n computers, this number should by also be divided by n.

Character set	Number of symbols in the set	3-symbol passwords		6-symbol passwords		8-symbol-passwords		12-symbol passwords
		Quantity	Time	Quantity	Time	Quantity	Time	Quantity	Time
Lower-case Latin letters	26	17,576	0,02 sec	308,915,776	5 min	208,827,064,576	58 hrs	95,428,956,661,682,176	3000 years
Lower case Latin letters and digits	36	46,656	0,04 sec	2,176,782,336	36 min	2,821,109,907,456	32 days	4,738,381,338,321,616,896	150,000 years
Lower- and upper-case Latin letters and digits	62	238,328	0,2 sec	56,800,235,584	15 hrs	2,183,40,105,584,896	7 years	3,226,266,762,397,899,821,056	100 million years
Lower- and upper-case Latin letters, digits and special symbols	94	830,584	1 sec	689,869,781,056	8 days	6,095,689,385,410,816	193 years	475,920,314,814,253,376,475,136	more than the Earth exists

Table - Quantity and time for brute-force on one computer, at a rate of 1 million passwords per second.