Generally, two encryption procedures are used: symmetric and asymmetric encryption. Each procedure has its advantages and disadvantages.

 

Symmetric

Symmetric encryption uses one key for encryption. The communication partner needs to comprise of the same key for decryption. This means, however, that a separate key must be used for every communication partner. The challenge here is the secure exchange and administration of the keys if a great number communication partners exists.
This type of encryption is not very computing-intensive and therefore fast and resource-friendly.

 

Asymmetric

Asymmetric encryption uses a key pair consisting of a public key and a private (or secret) key. The public key can be compared to a padlock and the private key to the matching key. Thus, the sender of an encrypted document only needs to know the recipient's "public key". Only the recipient will be able to decrypt the document again with the matching "private key".

This means that the "public key" can be given to any communication partner without further security measures and may be used several times.
However, this procedure is extremely computing-intensive and is therefore slow and consumes a great deal of resources.

 

Hybrid

The hybrid procedure benefits from the advantages of both symmetric and asymmetric encryption. Here, the document to be encrypted is encrypted quickly and in a resources-friendly manner with symmetrical encryption using a session key which is only used once. The symmetric session key is exchanged by means of asymmetric encryption. Due to these advantages, this procedure for document encryption has become the most popular and is used in the standard procedures S/MIME (X.509) and OpenPGP.

 

Incoming emails encrypted using this standard procedure are decrypted in an automated manner by the SEPPmail Secure E-Mail Gateway. This ensures that process remains completely transparent for the email recipient. The recipient receives the email in their mailbox in an unencrypted state and can read it without any additional effort, as has been the case so far.

 

To guarantee the authenticity of the sender and thus the integrity of the email content in addition to the confidentiality of an email ensured through its encryption, these are often additionally provided with electronic signatures. These are based on the asymmetric encryption procedure, which can naturally also be handled by the hybrid technologies.

 

An explanatory video for the encryption technologies can be found at our YouTube channel.