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Certificate Authority (CA)
Encryption decryption, Digital signature provider in India, Certificate Authority (CA), SSL, Secure Transaction
What is Certificate Authority?
In cryptography, a certificate authority or certification authority (CA) is an entity which issues digital certificates for use by other parties. It is an example of a trusted third party. CAs are characteristic of many public key infrastructure (PKI) schemes.
There are many commercial CAs that charge for their services. Institutions and governments may have their own CAs, and there are also free CAs.
A CA issues digital certificates which contain a public key
and the identity of the owner. The CA also attests that the
public key contained in the certificate belongs to the
person, organization, server or other entity noted in the
certificate. A CA's obligation in such schemes is to verify
an applicant's credentials, so that users and relying
parties can trust the information in the CA's certificates.
If the user trusts the CA and can verify the CA's signature,
then they can also verify that a certain public key does
indeed belong to whoever is identified in the certificate.
If the CA can be subverted, then the security of the entire
system is lost.
Suppose an attacker, Mallory (to use the Alice and Bob
convention), manages to get a CA to issue a false
certificate tying Alice to the wrong public key; the
corresponding private key is known to Mallory. If Bob
subsequently obtains and uses Alice's public key in this
(bogus) certificate, the security of his communications to
her could be compromised by Mallory - since Bob's messages
could be decrypted by Mallory, or he could be tricked into
accepting forged signatures from Alice.
What is a Digital Signature Certificate?
Digital Signature Certificates (DSC) are the digital
equivalent (that is electronic format) of physical or paper
certificates. Examples of physical certificates are drivers'
licenses, passports or membership cards. Certificates serve
as proof of identity of an individual for a certain purpose;
for example, a driver's license identifies someone who can
legally drive in a particular country. Likewise, a digital
certificate can be presented electronically to prove your
identity, to access information or services on the Internet
or to sign certain documents digitally.
World wide largest service providers
Worldwide, the certificate authority business is fragmented,
with national or regional providers dominating their home
market. This is because many uses of digital certificates,
such as for legally binding digital signatures, are linked
to local law, regulations, and accreditation schemes for
certificate authorities.
However, the market for SSL certificates (used for website
security) supports a number of multinational companies. A
2007 market share report from Security Space as of September
of that year determined that VeriSign and its acquisitions
(which include Thawte and more recently Geotrust) have a
57.6% share of the certificate authority market, followed by
Comodo (8.3%), GoDaddy (6.4%), DigiCert (2.8%), Network
Solutions (1.3%), and Entrust (1.1%).
Indian service
providers
Certification Agencies are appointed by the office of the
Controller of Certification Agencies (CCA) under the
provisions of IT Act, 2000. There are a total of seven
Certification Agencies authorised by the CCA to issue the
Digital Signature Certificates (DSCs). The details of these
Certification Agencies are available on the portal of the
Ministry www.mca.gov.in
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