Public Key Infrastructure (Digital Cert)

Public Key Infrastructure (PKI) allows users to information securely over an insecure network.  This can be done through the use of public key (known to all) and private key (will not be transferred over the network) (Brayton, Finneman, Turajski, & Wiltsey, 2006). PKI provides digital certificate that can identify an individual or an organization. In some cases, revocation of certification will be necessary (Brayton, Finneman, Turajski, & Wiltsey, 2006).

Previous cryptography involves the use of single key to encrypt and decrypt the data (symmetric cryptography). However such method is not as secure because if the key is intercepted by unauthorized user, the message can be decrypted by them (Brayton, Finneman, Turajski, & Wiltsey, 2006). Hence PKI is such more preferred. It is because it provides an additional layer of protection to prevent unauthorized user from decrypting the message upon intercepting the key (Khan, n.d.). PKI is also known as the asymmetric cryptography.

The following image will be showing the details about digital certificate:

Figure 1 (Digital Certificate showing the public key)

It must comprise certain component In order for PKI to work. This includes:

• Certificate Authority, one that issue and verify the authenticity of the digital certificate. This certificate will include or provide information about public key (Brayton, Finneman, Turajski, & Wiltsey, 2006).
• Registration Authority, one that verify the authenticity of the certificate authority before issuing digital certificate to individual or organization that requests it (Brayton, Finneman, Turajski, & Wiltsey, 2006).

There are two ways to send data across the network, either ensuring high confidentiality or high integrity. In order to ensure high confidentiality of the message, the sender will be encrypting the message using the receiver’s public key. The receiver will then be decrypting the data using his/her private key (Temasek Polytechinc, 2012).

To ensure high integrity of the message, the sender will be encrypting the message using his/her private key. The receiver will then be decrypting the data using the sender public key (Temasek Polytechinc, 2012).

Reference

Brayton, J., Finneman, A., Turajski, N., & Wiltsey, S. (2006, October). PKI (public key infrastructure). Retrieved May 25, 2012, from SearchSecurity: http://searchsecurity.techtarget.com/definition/PKI

Khan, S. (n.d.). What Is PKI? Retrieved May 25, 2012, from eHow: http://www.ehow.com/about_6693189_pki_.html

Temasek Polytechinc. (2012, May 25). Cryptography. Singapore, Singapore, Singapore.