“What is the difference between SSH and SSL?” you may wonder. and “Which is better: SSH or SSL?” The cafeteria in our office would be much busier if we were given a dime every time anyone posed this question to our customer service team. Although having some extra cash will be great, we can at least get our coffee on time. Before you pass judgement on me, let’s get to the point: SSH vs SSL (or SSL vs SSH, if you prefer).
It’s understandable that people are confused about the differences between SSH and SSL. SSH and SSL are completely different things, despite the fact that they both encrypt data from one endpoint to another and share two of the same letters in their names.
We’ll look at all of these security protocols in this blog post to help you understand what they are, why they’re used, and which one is best for you. We’ll also put an end to the whole “SSH vs SSL” debate. Let’s get this party started!
SSL: The Bedrock of Web Security
SSL (secure socket layer) is a security protocol for creating a secure connection between clients (web browsers) and web servers. In other words, SSL ensures that data sent between browsers and web servers is protected and cannot be intercepted or manipulated by an unauthorised party in the middle.
TLS (transport layer security) is a term that you may be unfamiliar with. TLS, on the other hand, is an improved variant of the SSL protocol. SSL versions 2.0 and 3.0 are no longer supported and have been replaced by improved TLS versions (TLS 1.2 & 1.3). The word “SSL” is used because it has been around for a longer time and is more common. In general, both words are used interchangeably since they both shield users from man-in-the-middle (MiTM) attacks.
An SSL/TLS certificate is used to apply the SSL/TLS protocol, which operates on port 443, to the web server. This certificate should be mounted on the web server so that safe connections with clients can be established.
Functions of SSL/TLS
As we’ve seen, SSL/TLS protects our data when it’s in transit across the internet, ensuring that it’s safe from malicious actors. This is accomplished by SSL/TLS certificates performing two vital functions: data encryption and authentication.
Every day, billions of people transmit confidential information over the internet. Passwords, credit card numbers, social security numbers, personal images, and business documents are all examples. It is difficult to have the internet world without protecting this data.
This is where SSL/TLS enters the image. All data exchanged between SSL-enabled servers and web browsers is encrypted with SSL/TLS certificates. This encryption is achieved by the use of strong encryption algorithms that are almost impossible to break.
Encryption is useful for data security, but it’s useless if we’re communicating with a rogue server or a malicious client. This is where the authentication process kicks in, and the server’s identity verification becomes a critical part of the security equation. The browser must first confirm the identity of the website in question before an encrypted link can be created through the secure SSL/TLS protocol. This is accomplished in part by validating the site’s SSL/TLS certificate.
Based on public key cryptography, an SSL/TLS certificate may only be issued after a person’s or organization’s identity has been confirmed by a trusted third-party certificate authority (CA).
How SSL/TLS Works
Two encryption keys are used in public key encryption, also known as asymmetric encryption: a public key and a private key. Both keys are distinct and come in pairs, despite the fact that they are mathematically connected. That is why they are referred to as a “primary pair.”
The public key, as the name suggests, is open to the general public. On the other side, the private key is expected to be kept safe on the web server. The data is encrypted using the public key, and decrypted using the private key. The private key is included in the SSL/TLS certificate issued by a certificate authority, which serves as the foundation for the public key infrastructure (PKI).
An SSL/TLS certificate consists of a collection of files that must be installed on your computer. However, the reason it’s called a “certificate” is that it serves as proof of identity. When you request an SSL certificate for your website, the certificate authority verifies your identity (depending on the type of SSL certificate) and only issues the certificate after you successfully complete the vetting process.
If you want to grant an SSL certificate in your company’s name, the CA will check your company’s legitimacy against the CA/Browser Forum’s requirements. Then and only then can you receive an SSL certificate.
Uses of SSL/TLS in Data Security
An SSL certificate is used to:
- Protect online credit card/banking transactions;
- Protect user credentials and any sensitive information transmitted online;
- Protect the connection between email clients and email servers;
- Protect the transfer of files over HTTPS and FTP(s) services;
- Protect hosting control panels; and
- Protect intranet-based traffic.
SSH: A Method to Secure Remote Communication
Safe shell (SSH) is a cryptographic protocol that enables network services to be encrypted over an unsecured network. SSH is often used to secure remote logins from one device to another. It accomplishes this by ensuring the protection and dignity of the two endpoints. It’s a far more robust alternative to unreliable protocols like FTP.
SSH is a godsend in today’s world, where remote working is becoming the norm. DNS spoofing, IP source routing, data manipulation, data sniffing during transmission, IP address spoofing, and so on are all covered.
SSH, which operates on port 22, is used to execute commands remotely by communicating with the running shell of another device. SSH was designed for UNIX-based machines, but it is now simple to implement on Windows.
Functions of SSH
One of the reasons why people get into the “SSH vs SSL” (or “SSL vs SSH”) argument is that both protocols perform almost identical functions, although at different locations. SSH has two key features, similar to SSL: encryption and authentication.
Encryption: Although traditional login methods such as Telnet, rlogin, and FTP do not provide protection, SSH provides a safe alternative by encrypting data. SSH, like SSL, is a client-server protocol that encrypts all data sent between two endpoints.
Authentication is one of the most important features to have in any login form. Do you want some unauthorised individual to have access to your organization’s systems? By employing strong authentication via identity verification, SSH removes this risk.
How SSH Works
Another explanation why people get confused about SSH and SSL is that they all work in the same way. SSH, like SSL/TLS, uses public key cryptography (also known as asymmetric encryption).
As you would expect, this approach also employs the use of a cryptographic key pair, consisting of a public and private key. As a result, one private key would be associated with only one public key, and vice versa. These keys are often referred to as “SSH keys.”
The server is supposed to keep the public key, while the client demanding remote access is supposed to keep the private key. When a user requests remote access, the server verifies the private key and only then grants remote access to that user.
Uses of SSH in Network Security
SSH is commonly used for the following purposes:
Providing users and automated processes with safe remote access; allowing collaborative and automated file transfers; and issuing remote commands.
SSH vs SSL: The Difference
SSL and SSH, as we’ve shown, are not only identical in terms of their names, but also in terms of their roles and how they work. However, there is a one-letter difference between them, which accounts for two distinct distinctions.
The application is the first distinction between SSL and SSH. SSL is primarily used to build a secure link between a website and its visitors, while SSH is used to develop secure remote connections on insecure networks.
The second distinction between SSL and SSH is the way they both function. Although both SSH and SSL use public key cryptography, SSL also uses public key infrastructure. It entails the use of digital certificates and, as a result, requires the use of CAs. SSH, on the other hand, uses only the key exchange and does not use digital certificates. To put it another way, an entity that wants to use SSH doesn’t need to go to a certificate authority. It has the ability to create its own key pairs and distribute them to the required users.
SSL vs SSH: A Side-by-Side Comparison
|Stands for “secure socket layer.”||Stands for “secure shell.”|
|SSL is a security protocol.||SSH is a network cryptographic network protocol.|
|Runs on port 443.||Runs on port 22.|
|Used primarily to establish secure connections between web servers and clients (web browsers).||Typically used for secure communication with a remote computer.|
|Authentication is done by employing an X.509 digital certificate (SSL/TLS certificate).||Authentication is done by a three-step process: server verification, session key generation, and client authentication.|
|SSL works based on SSL/TLS certificates.||SSH works based on network tunnels.|
|Primarily used to protect against man-in-the-middle (MiTM) attacks and identity theft.||Protects against DNS spoofing, IP source routing, data manipulation, data sniffing during transmission, Spoofing of IP addresses, etc.|
Conclusion on the SSH vs SSL Debate
By now, you’ve probably realised that there can’t be a true comparison of “SSL vs SSH” because they’re completely different, no matter how close they seem. It is not possible to use one at the cost of the other. It’s likely that you’ll need SSL, SSH, or both. It all depends on what you’re trying to defend yourself from or achieve. One thing is certain: they are both good practises, and you can use them whenever possible.