Slovakia
Performance
Development
Content
Strategy
AI and process automation

SSL (Secure Sockets Layer)

SSL (Secure Sockets Layer) is a standard security protocol technology creating an encrypted connection between a web server and a visitor's browser. This connection ensures that all data transferred between the user and the site (passwords, personal details, credit card numbers) stays private and protected against attack and unauthorised reading. The original SSL protocol has since been replaced by its more modern, more secure successor TLS (Transport Layer Security), although in everyday practice the term SSL is still used.

You can recognise a website secured with an SSL certificate by two main signs:

  1. A padlock icon in the browser's address bar.
  2. The HTTPS protocol (Hypertext Transfer Protocol Secure) instead of the original unsecured HTTP.

Without an SSL certificate, data is sent in plain text. That means any hacker on the same network (on public Wi-Fi, for instance) could eavesdrop on the communication and steal sensitive information. SSL uses asymmetric encryption with a public and a private key, which turns the information into an unreadable jumble of characters for any third party.

Advantages

  • Protecting sensitive data: it encrypts communication, protecting customers' login credentials, payment information and personal documents.
  • Building trust: sites with the padlock look professional and secure. Visitors are not afraid to buy on them.
  • SEO support (a ranking factor): Google has officially confirmed that HTTPS is one of the factors affecting position in search results. Secured sites have priority.
  • Authentication: an SSL certificate confirms you are sending information to the genuine server owned by that company and not to a fraudulent page.
  • Regulatory compliance (GDPR): for e-shops and sites collecting personal data, encrypting data in transit is one of the basic privacy protection requirements.

Disadvantages

  • Certification costs: although free certificates exist (Let's Encrypt), special certificates with a higher level of validation (OV and EV certificates) carry annual fees.
  • The need for administration: SSL certificates have a limited validity (usually 3 to 13 months) and have to be renewed regularly, otherwise the site becomes inaccessible.
  • A slight increase in latency: encrypting and decrypting data takes some computing time, which can lengthen page loading by milliseconds (on modern servers this is all but imperceptible).
  • Migration problems: moving from HTTP to HTTPS requires redirects (301) to be set up correctly, otherwise organic positions can temporarily drop.

Practical example

Imagine a customer in an internet café entering their card details on your e-shop.

  • Without SSL: a hacker connected to the same Wi-Fi can capture the card number and the CVV code with simple software, because the data travels through the air as unprotected text.
  • With SSL: the data is encrypted before sending into a format that looks something like “xY9!2Lp0z…”. Even if a hacker intercepts it, it is completely useless without the special private key held only by your server. Your e-shop is protected against abuse and the customer is safe.