
Q: How secure is the encryption used by SSL?
A: It would take significantly longer than the age of the universe
to crack a 128-bit key.
SSL uses public-key encryption to exchange a session key between
the client and server; this session key is used to encrypt the http
transaction (both request and response). Each transaction uses a
different session key so that even if someone did manage to decrypt
a transaction, that would not mean that they would have found the
server's secret key; if they wanted to decrypt another transaction,
they'd need to spend as much time and effort on the second transaction
as they did on the first. Of course, they would have first have
to have figured out some method of intercepting the transaction
data in the first place, which is in itself extremely difficult.
It would be significantly easier to tap your phone, or to intercept
your mail to acquire your credit card number than to somehow intercept
and decode Internet Data.
Servers and browsers do encryption ranging from a 40-bit secret
key to a 128-bit secret key, that is to say '2 to the 40th power'
or '2 to the 128th power'. Many people have heard that 40-bit is
insecure and that you need 128-bit to keep your credit card info
safe. They feel that using a 40-bit key is insecure because it's
vulnerable to a "brute force" attack (basically trying
each of the 2^40 possible keys until you find the one that decrypts
the message). This was in fact demonstrated when a French researcher
used a network of fast workstations to crack a 40-bit encrypted
message in a little over a week. Of course, even this 'vulnerability'
is not really applicable to applications like an online credit card
transaction, since the transaction is completed in a few moments.
If a network of fast computers takes a week to crack a 40-bit key,
you'd be completed your transaction and long gone before the hacker
even got started.
Of course, using a 128-bit key eliminates any problem at all because
there are 2^128 instead of 2^40 possible keys. Using the same method
(a networked of fast workstations) to crack a message encrypted
with such a key would take significantly longer than the age of
the universe using conventional technology. Remember that 128-bit
is not just 'three times' as powerful as 40-bit encryption. 2^128
is 'two times two, times two, times two...' with 128 two's. That
is two, doubled on itself 128 times. 2^40 is already a HUGE number,
about a trillion (that's a million, million!). Therefor 2^128 is
that number (a trillion), doubled over and over on itself another
88 times. Again, it would take significantly longer than the age
of the universe to crack a 128-bit key.
Key Size
Possible Key Combinations
2-bit 2^2 2x2 = 4
3-bit 2^3 2x2x2 = 8
4-bit 2^4 2x2x2x2 = 16
5-bit 2^5 2x2x2x2x2 = 32
6-bit 2^6 2x2x2x2x2x2 = 64
7-bit 2^7 2x2x2x2x2x2x2 = 128
8-bit 2^8 2x2x2x2x2x2x2x2 = 256
9-bit 2^9 2x2x2x2x2x2x2x2x2 = 512
10-bit 2^10 2x2x2x2x2x2x2x2x2x2 = 1024
11-bit 2^11 2x2x2x2x2x2x2x2x2x2... = 2048
12-bit 2^12 2x2x2x2x2x2x2x2x2x2... = 4096
16-bit 2^16 2x2x2x2x2x2x2x2x2x2... = 65536
24-bit 2^24 2x2x2x2x2x2x2x2x2x2... = 16.7 million
30-bit 2^30 2x2x2x2x2x2x2x2x2x2... = 1 billion (1,073,741,800)
40-bit 2^40 2x2x2x2x2x2x2x2x2x2... = 1 trillion (1,097,728,000,000)
56-bit 2^56 2x2x2x2x2x2x2x2x2x2.... = 72 thousand quadrillion (71,892,000,000,000,000)
128-bit 2^128 2 multiplied by 2
128 times over. = 339,000,000,000,000,000,000,000,000,000,000,000
(give or take a couple trillion...)
Doing the math, you can see that using the same method that was
used to break 40-bit encryption in a week, it would take about 72
million weeks (about 1.4 million years) to even break '56-bit medium'
encryption and significantly longer than the age of the universe
to crack a 128-bit key. Of course the argument is that computers
will keep getting faster, about doubling in power every 18 months.
That is true, but even when computers are a million times faster
than they are now (about 20 years from now if they double in speed
every year), it would then still take about 6 thousand, trillion
years, which is about a million times longer than the Earth has
been around. Plus, simply upgrading to 129-bit encryption would
take twice as long, and 130-bit would take twice as long again.
As you can see, it's far easier for the encryption to keep well
ahead of the technology in this case. Simply put, 128-bit encryption
is totally secure.
Q: How do I know if encryption is enabled or not?
A: Your Browser (Netscape or Internet Explorer) will tell you.
In Netscape versions 3.X and earlier you can tell what kind of encryption
is in use for a particular document by looking at the "document"
information" screen accessible from the file menu. The little
key in the lower left-hand corner of the Netscape window also indicates
this information. A solid key with three teeth means 128-bit encryption,
a solid key with two teeth means 40-bit encryption, and a broken
key means no encryption. Even if your browser supports 128-bit encryption,
it may use 40-bit encryption when talking to other servers or to
servers outside the U.S. and Canada. In Netscape versions 4.X and
higher, click on the "Security" button to determine whether
the current page is encrypted, and, if so, what level of encryption
is in use.
In Microsoft Internet Explorer, a solid padlock will appear on
the bottom right of the screen when encryption is in use. To determine
whether 40-bit or 128-bit encryption is in effect, open the document
information page using File->Properties. This will indicate whether
"weak" or "strong" encryption is in use.
Q: What about warnings or errors about the Secure Certificate?
A: Your personal Security settings will determine what warnings
you see.
Depending on how your security settings are setup in your Browser,
you may also see information about our Certificate when you enter
the secure directories. This information will usually include the
Dates that the Certificate is valid for, the site name that the
Certificate has been issued to, and the Certificate Authority (or
'CA') that issued the Certificate. You can also usually view the
Certificate to see information about the various parties, including
Inet2000 and our CA.
The most common warning is that you have not previously chosen
to Trust the authority. This is a normal warning if you haven't
already purchased anything online from a Merchant who's certificate
was issued by a Certificate Authority that you haven't told your
browser to trust from now on. Of course, you may well have no errors,
warnings or information screens at all - again, largely depending
on the way you've got your security settings set in your Browser.
In any case, the encryption level and the security is the same
whether you've got your settings low (don't warn me about anything)
or very high (warn and inform me about everything). Either way,
your data is still encrypted and still secure.
Q: What happens when the Credit Card is actually processed.
A: The transaction is totally secure.
At Saveonboating.com, the security of your personal information
is paramount. All Credit Card Transactions are completed using a
128 Bit SSL Encrypted Secure Transaction. As we transmit the information
to the Bank's Secure SSL Server, they require a 128-bit transaction
and will not process a transaction without one. Even though 40 or
56 Bit transactions are very secure, our Bank's insistence on 128
Bit SSL means that there is never any chance of your information
every being intercepted or decoded. Again, your security is of paramount
importance for us.
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