However, this does not mean that asymmetric keys are better. Since asymmetric keys are bigger than symmetric keys, data that is encrypted asymmetrically is tougher to crack than data that is symmetrically encrypted. SSL Certificates do not dictate what key size is used. Whether a 128-bit or 256-bit key is used depends on the encryption capabilities of both the server and the client software. As you can imagine, a ‘brute force’ attack (in which an attacker tries every possible key until they find the right one) would take quite a bit of time to break a 128-bit key. Symmetric key sizes are typically 128 or 256 bits-the larger the key size, the harder the key is to crack.

Both the sender and the receiver need the same key to communicate. Symmetric encryption (or pre-shared key encryption) uses a single key to both encrypt and decrypt data. To put it into perspective, it would take an average computer more than 14 billion years to crack a 2048-bit certificate. Though larger keys can be created, the increased computational burden is so significant that keys larger than 2048 bits are rarely used. 2048-bit keys have enough unique encryption codes that we won’t write out the number here (it’s 617 digits). However, keys smaller than 2048 bits are no longer considered safe to use. The most common asymmetric encryption algorithm is RSA however, we will discuss algorithms later in this article.Īsymmetric keys are typically 1024 or 2048 bits. This way only the intended receiver can decrypt the message. However, decryption keys (private keys) are secret. Anyone can use the encryption key (public key) to encrypt a message. Asymmetric EncryptionĪsymmetric encryption (or public-key cryptography) uses a separate key for encryption and decryption. It also covers different types of algorithms that are used to create these keys-including the mathematical equations that make them virtually impossible to crack. It covers asymmetric and symmetric keys and how they work together to create an SSL-encrypted connection. This article explains the technology at work behind the scenes of SSL encryption. To establish this secure connection, the browser and the server need an SSL Certificate.īut how is this accomplished? How is data encrypted so that no one-including the world’s biggest super computers-can crack it? It allows sensitive information such as credit card numbers, social security numbers, and login credentials to be transmitted securely.

SSL (Secure Sockets Layer) is a standard security technology for establishing an encrypted link between a server and a client-typically a web server (website) and a browser or a mail server and a mail client (e.g., Outlook).

How does ssl work