- 1. Presentationon DigitalSignatures!
2.
- How Encryption and Digital Signatures Work
- Digital signature overview
- Definition of digital signature
- Advantages and Disadvantages
3.
- Encryption is the conversion of data into a form, called
aciphertext .
- The use of encryption/decryption is as old as the art of
communication.
- Encryption/decryption is especially important
inwirelesscommunications.
- Encryption/decryption is a good idea when carrying out any kind
of sensitive transaction .
- such as a credit-card purchase online, or the discussion of a
company secret between different departments in the
organization.
4.
- -Private key means that each computer has a secret key (code)
that it can use to encrypt a packet of information before it is
sent over the network to the other computer.
- Private key requires that you know which computers will talk to
each other and install the key on each one.
5. Private key encryption is essentially the same as a secret
code that the two computers must each know in order to decode the
information. The code would provide the key to decoding the
message.Think of it like this. You create a coded message to send
to a friend where each letter is substituted by the letter that is
second from it. So "A" becomes "C" and "B" becomes "D". You have
already told a trusted friend that the code is "Shift by 2". Your
friend gets the message and decodes it. Anyone else who sees the
message will only see nonsense . 6.
- - Public key encryption uses a combination of a private key and
a public key. The private key is known only to your computer while
the public key is given by your computer to any computer that wants
to communicate securely with it. To decode an encrypted message, a
computer must use the public key provided by the originating
computer and it's own private key.
7. The key is based on a hash value. This is a value that is
computed from a base input number using a hashing algorithm. The
important thing about a hash value is that it is nearly impossible
to derive the original input number without knowing the data used
to create the hash value. Here's a simple example:Input number
Hashing algorithm Hash value 10667 Input # x 143 1525381 8.
- How Encryption and Digital Signatures Work
- This is a very basic introduction to encryption and digital
signatures.
- It explains how they work and gives some examples of how they
are used. Encryption scrambles or modifies a message or document so
it cannot be read and understood, except by the intended recipient.
A key is necessary to reverse the scrambling or modification, to
make the message readable.
- Encryption is used for secrecy in communication.
9. Digital signatures are used to verify that a message or
document was authored by a certain person, and that it was not
altered or modified by anyone else. Encryption and digital
signatures can be used together, or separately a message may be
encrypted, but not digitally signed (only people with the key can
read it, but the reader cannot be certain who actually wrote it)
10.
- a message may be digitally signed, but not encrypted (everyone
can tell who wrote it, and everyone can read it)
- a message may be encrypted first, then digitally signed (only
someone with the key can read it, but anyone can tell who wrote
it)
- a message may be digitally signed first, then encrypted (only
someone with the key can read it, and only that same reader can be
sure who sent the document)
11.
- Encryption depends on modifying or scrambling messages so a key
is necessary to understand the message.
- As an example, suppose we take a message and change each letter
of the alphabet by substituting a later letter.
- If the key is 1, then choose the next letter: A becomes B, B
becomes C, C becomes D, and so on.
- If the key is 2, then choose the letter two letters later: A
becomes C, B becomes D, C becomes E, and so on.
12. For other keys, use the key to skip the specified number of
letters. If the original message is CATS HAVE FUR then the
encrypted version depends on the key as follows: (key = 1) DBUT
IBWF GVS (key = 2) ECVU JCXG HWT (key = 3) FDWV KDYH IXU ...and so
forth 13.
- Digital Signatures Overview
- Sign the document in another fashion.
- This is referred to as a digital signature .
- Digital signatures are ways of providing the legal proof
necessary to confirm a document as being authentic.
- Who those who are not familiar with digital signatures, the
question remains:
- --What is a digital signature ?
- --How is it implemented ?
14.
- What is a digital signature?
- A digital signature is an electronic signature.
- A digital signature is a term used for marking or signing an
electronic document by a process meant to be analogous to paper
signatures.
- A digital signature is an electronic construct that purports to
replace in an electronic world what is called wet or ink signatures
in the paper world.
- A digital signature is basically a way to ensure that an
electronic document (e-mail, spreadsheet, text file, etc.) is
authentic. Authentic means that you know who created the document
and you know that it has not been altered in any way since that
person created it.
15.
- Use of digital signature?
- The purpose of a digital signature is the same as your
handwritten signature.
- A digital signature uses digital keys (public-key
cryptology).
- A digital signature attaches the identity of the signer to the
document and records a binding commitment to the document.
16. To use digital signature software requires some initial
setup: you will need a signing certificate.Digital signatures can
help you save time and paper-handling costs. Example: If in your
business you commonly sign documents or need to verify the
authenticity of documents. 17.
- What is needed to create a digital signature?
- You will need to get your personal signing certificate.
- Creating your certificate involves creating a public-private
digital key pair and a Certificate Authority.
- The process of creating your public-private key pair is easy
and quick.
- Thepublic key certificate creates proof of the identityof the
signer by using the services of a certificate authority.
- A certificate authority uses a variety of processes to
associate the particular public key with an individual.
- The combination of your public key and proof of identity result
in a public key certificate - also called a signer's
certificate.
18.
- How Digital Signature Works
- A digital signature is generated by your email software and
your private key, working together.
- Your message's signature generates according to standardsPGP,
so the receiver must also have that standard supported.
- The use of digital signatures usually involves two processes,
one performed by the signer and the other by the receiver of the
digital signature.
19.
- Digital Signature Creation:
- - uses a hash result derived from and unique to both the signed
message and a given private key.
- For the hash result to be secure, there must be only a
negligible possibility that the same digital signature could be
created by the combination of any other message or private
key.
20. The formula depends on two inputs: the sequence of
characters representing the electronic data to be signed, and a
secret number referred to as a signature's private key, associated
with the signing party and which only that party has access to. The
resulting computed value, representing the digital signature, is
then attached to the electronic data just as a paper signature
becomes a part of a paper document. 21.
- Digital Signature Verification -
- It is the process of checking the digital signature by the
reference to the original message and a given public key.
- Verifying also relies on a formula.
22. Here, the formula depends on three inputs: The sequence of
characters representing the supposedly originally signed electronic
data, the public key of the signing party, and the value
representing the supposedly authentic digital signature.The output
of the formula is a simple answer: yes or no. 'Yes' signifies that
the digital signature is indeed an authentic digital signature on
the presented electronic data, and it is associated with the party
linked to the public key being used. 23. 24.
- Legal Aspects of Digital Signatures
- The digital signature is what makes a document a legal.
- It is a representation of assuring the document meats all legal
and is authentic in its framework
- So the information in the document can be put into action.
- The actual digital signature provides the following:
25. Evidence: In order for the document to have power, the
originator has to prove he or she is the sole owner and executioner
of the document.This is what the digital signature does. It
provides the necessary evidence to those viewing the document that
it is real and the person signing it is real.Ceremony:Basically,
any time a document is signed it is based on a ceremony or
tradition of making the document legal.Without the signature, the
document would not be validated as authentic and legal.Providing a
digital signature proves that the signor is entering into a
commitment voluntarily 26. Approval :As is stated by law, when a
document must be made legal, it needs to be approved in order for
the information to be turned legal and acted on. By placing a
digital signature on the document makes it this way.This way the
document can be acted on in a legal way. Efficiency:One thing the
digital signature does is if saves time and money because the
signature turns the document instead a legal transaction.This way
no further inquiries are needed to verify or clarify the
information on the document, as being legit or not. 27. The Noble
County Surveyor's Office uses a digital signature system on their
publicly signed papers. This means your signature is securely
applied to a digital document. Its more secure than a pen and ink
signature, and it saves paper and time.
28.
- You are applying for a building permit - you stop by our office
and have a drainage check done (that is, we inspect your property
for any tiles or open drains that you will need to work
around).
- A document is generated on our computer that explains what was
found on your property, it tells the Building Department if/what
precautions need to be taken before you build.
- Before this document is printed it needs your signature. We
have a black box a digital signature pad that you will sign. As you
write the signature is being digitally burned into the
document.
- This is a very secure system. It is encrypted and date stamped
to help prove your signature
29.
- Authentication , identification of theperson that signs.
- No replacement , the signature was made by
- the person that signed using devices under
- Advantages and Disadvantages of DigitalSignatures
Integrity of data , every change will be detected;No repudiation
, because the author can not denied that he has written and sent;
30. TheAdvantagesof using digital signatures include:Imposter
prevention:By using digital signatures you are eliminating the
possibility of committing fraud by an imposter signing the
document. Since the digital signature cannot be altered, this makes
forging the signature impossible. Message integrity: By having a
digital signature you are in fact proving the document to be valid.
You are assuring the recipient that the document is free from
forgery or false information. 31.
- Using a digital signature satisfies some type of legal
requirement for the document in question. A digital signature takes
care of any formal legal aspect of executing the document.
- Thedisadvantagesof using digital signatures involve the primary
avenue for any business: money.
- This is because the business may have to spend more money than
usual to work with digital signatures including buying certificates
from certification authorities and getting the verification
software.
32. Q U E R I E s ? 33. Thank you& Signing off Silpa END