As a business owner, you know how important it is to secure your data. In the process, you have probably come across some unfamiliar terms, like key cryptography, RSA, VPN and PKI.
And you may be asking yourself whether you need key cryptography in your business.
And the short answer is, yes you do – and you are probably using it already and don’t know it. For example, if you own a website, you very likely also have an SSL certificate to keep your site secure.
In this post, we will give you some insight into key cryptography, explain the differences between private and public keys as well as give you some examples or use cases in the hopes of demystifying this rather technical subject.
What is Key Cryptography?
Key cryptography is a form of digital security to lock away your sensitive data using encrypted keys or codes. This is called encryption and it is done using a string of random numbers or letters.
The idea is that you can only access this data by opening it (or decoding it) with the correct key. This is called decryption.
There are two different types of key encryption, private key (symmetric) encryption and public-key (asymmetric) encryption, briefly explained below.
Private Key Encryption
With Private Key or Symmetric Key encryption, you use the same key for coding and decoding data (encrypting and decrypting). The key must be kept secret and sharing the key can create risk.
Public Key Encryption
With public key or asymmetric encryption, you use separate keys to code and decode data.
With public key encryption, you can share the key with anyone because you keep your decryption key to yourself.
Together, these keys assist with ensuring the security of data that is exchanged.
A message that is encrypted with asymmetric encryption cannot be decoded without using a corresponding private key.
For more in-depth information about the differences between asymmetric and symmetric encryption, check out this post from Keyfactor.
Summary: Public Keys vs Private Keys
- Public Keys – Enable users to code a message to other people on the system. You can confirm the signature signed by a person’s private key.
- Private Keys – Enables you to decode a message that is secured by your public key. The message can be signed by you with your private key to notify recipients that the message can only be sent from you.
Private and Public Key Cryptography Use Cases
Basic Encryption
For basic encryption, like encrypting files on your PC’s hard drive, symmetric (private) key encryption would suffice.
Symmetric encryption only needs you to remember and maintain a single key and a single decryption step is all that is needed to decode the data in a readable format.
If you have a safe way of communicating a private key to multiple users, you can also utilize private key cryptography to share data across your network.
Any authorized users will then have access to concealed content, using the same key.
Correspondence via The Internet
Encryption is useful for keeping emails secure, however, you can face a dilemma when you are contacting someone new.
If a private encryption system is used, you must send the key, however, this might permit an outsider to get access to your email which will render the encryption useless.
Public key encryption is useful for permitting multiple users to exchange public keys. Because public keys cannot decrypt public key-encrypted messages, this means two users can converse utilizing encryption that is exclusive to their conversation.
This kind of transfer also plays a significant role with SSL, when your browser encrypts a private key utilizing the public key of your server. This way the system ensures no one can steal the key that is in transit.
Verification and Identification
Another benefit of public-key encryption is the system’s ability to act as identification. If you decrypt a familiar string of data using your private key and attach it to a message, any user who received the message can decrypt it using your public key.
This way, the encryption is like a fingerprint, because only your private key could be used for encrypting the data. Another strategy involves running the document via a hash function, basically a one-way cryptographic decryption that creates a unique result for every input.
By hashing your message and decrypting the hash utilizing your private key, you are not just proving your identity to the intended recipient, you are also ensuring that no one could tamper with the message, because the hash would be altered.
Digital Signatures
To make the most of public key encryption, you must give access to your public key. If you are sending private correspondence, merely appending the key to the message board signature or email may suffice, however, businesses that want to use public key encryption for transacting business must complete an extra step.
A digital signature offers a record of your business or server information and your public key for users to access, permitting your identity to be confirmed.
Services like these cost money, however, your certificate must be kept current to take full advantage of SSL and other procedures that encrypt data transfers.
Takeaway
Although it’s almost impossible to get away from key cryptography in any business in this day and age, fortunately, you don’t need to understand all the technical details.
It’s enough to know just this: –
Private and Public keys are essential for businesses to provide strong encryption and to keep their data secure. Their job is to prevent outsiders from getting access to sensitive business data, and worse, altering or changing it in any way.