Overview:
Thawte® SSL Web Server Certificates secure confidential information exchanged online and confirm your site's identity to employees, business partners, and other users. When users click the Thawte® Trusted Site Seal or view certificate details, your organization name appears and shows that Thawte, a trusted certificate authority, has verified the site's identity. SSL Web Server Certificates include full organization authentication, the Thawte Trusted Site Seal, free reissues, and a 30-day money back guarantee.
How SSL Works
SSL is a reasonably straightforward protocol, despite the advanced math that makes it work.
Public and Private Keys
SSL uses public and private encryption keys. When a digital certificate is issued for a web server, that certificate contains two keys: one that is privately held by the web server ("private key"), and another that is made publicly available to anyone who requests it ("public key"). These two keys are asymmetric, which means:
- Data encrypted by the private key can only be decrypted by the public key
- Data encrypted by the public key can only be decrypted by the private key
For example, to ensure the privacy of communications, a web browser retrieves the server's public key. The browser then uses that key to encrypt the information to be transmitted, since only the web server holds the private key necessary to decrypt that information. Note that in practice the encryption process may also rely on randomly-generated, short-term session keys that are exchanged between the browser and server. This is because, in most cases, the browser does not possess its own digital certificate and key pair.
How is an SSL Session Created?
An SSL session begins when a web browser sends a request to a web server using the https:// protocol

The web server responds with its digital ID, which includes its public encryption key. The web browser verifies the digital ID, which may include an online check with the CA as well as a check of the certificate itself for validity dates and other details. Once verified, the browser generates a session key, encrypts the session key using the server's public key, and sends the package back to the server.
The server decrypts the session key by using the server's private encryption key, which only the server possesses. This ensures that only the browser and the server possess the session key, and they can use that shared key to encrypt further communications between them. Servers usually discard session keys after several minutes of inactivity.
Choosing a Certificate:
The right SSL certificate depends on the level of assurance your customers need and the minimum security level your organization requires.
Assurance and Authentication
Authentication means that a trusted third party (such as Thawte) has verified the identification information contained in your SSL certificate, assuring customers that your site is actually your site.
You are considering: SSL Web Server Certificates with full organization validation. Your domain name and validated organization name are included in certificate details and verification pages to assure users.
For the most assurance, SSL Web Server Certificates with EV turn the address bar green in high-security web browsers, showing that your organization has met the industry's highest standard of authentication. Extended Validation (EV) includes your domain name, organization, and location in certificate details and verification pages.
2More Assurance. 3Most Assurance.
Security and Encryption
Encryption is the "secret code" used to keep online communications private when a web browser and web server talk to each other.
You are considering: SSL Web Server Certificates with 128-bit or 256-bit encryption in the latest operating systems and web browsers. However, certain older browsers and operating systems only connect at 40-bit or 56-bit.
For strong encryption in the most browsers, SGC SuperCerts with server-gated cryptography (SGC) enable older browsers and operating systems to step up to 128-bit or 256-bit encryption.
2More encryption. 3Strong encryption.
If you need both Extended Validation and SGC, consider a VeriSign Secure Site Pro with EV SSL Certificate.