Stream Cipher:

A stream cipher encrypts in small units, often a bit or a byte at a time, but unlike a basic block cipher the output corresponding to a given input will depend on where in the message it occurs. The simplest type of stream cipher uses a complicated function, which retains state, to generate a psuedo-random sequence which is then combined with the input using a simple operation such as bytewise addition.

Symmetric Cryptography:

A symmetric cipher is one in which the same key is used for encryption and decryption. Therefore a secure method has to be found by which the sender and recipient can agree on the key. IDEA, RC4 are symmetric ciphers.

TLS:

TLS, standing for Transport Layer Security, is the latest version of SSL. It is an enhancement of SSL version 3.0, and is a proposed Internet Standard (see RFC2246).

Thawte:

Thawte is a South African company which acts as a certificate authority. On December 20, 1999, it was acquired by Verisign.

Triple DES:

Each block is encrypted three times using DES, using at least two different keys. There are variants which differ in whether two or three keys are used, and whether some of the steps are in decryption mode. In SSL, three separate keys are used, and the middle step is a decryption.

Verisign:

Verisign is the dominant certificate authority on the internet at the present time, though many of its certificates are signed as RSA Data Security. Early versions of Microsoft and Netscape browsers had RSA Data Security configured as the only trusted certificate authority, and this more or less mandated that people wishing to use certificates on the internet need to obtain them from Verisign, and use server software that had been accredited by Verisign. Current versions of the Microsoft & Netscape browsers have the facility for users to add new certificate authorities, and, as older versions of the browsers have been replaced, there has been an opportunity for new certificate authorities such as Thawte to emerge.

X.509:

An International Telecommunication Union recommendation for the format of certificates.