RAT or Remote Access Trojan is malware that provides back door access for hackers to control the target computer. The hacker can then use the compromised machine to distribute to other vulnerable users and create a botnet. RAT users can potentially access sensitive information, delete file systems and further distribute malware.
A Registrar is an organisation in charge of selling domain names. SSL247® is a Registrar
A Registry is a term often used to talk about registry operator. It is the organisation in charge of a domain name extension. To become a registry, you must sign an agreement with the ICANN.
Registration Authority (RA)
Some CAs delegate their authentication to a Registration Authority (RA). CAs delegate their responsibility for the identification and authentication of an applicant for a SSL certificate - which is how CA Comodo was manipulated into issuing fraudulent certificates. SSL247® has always been against the RA model, as we believe the responsibility of vetting/authentication should be the sole responsibility of the CA.
A certificate authority can issue multiple certificates in the form of a tree structure. A root certificate is the top-most certificate of the tree, the private key of which is used to "sign" other certificates. All certificates immediately below the root certificate inherit the trustworthiness of the root certificate. Certificates further down the tree also depend on the trustworthiness of the intermediates. In order for your certificate to work across as many devices and platforms as possible, you will need to install intermediate certificates as well as your own certificate. (Full, easy to follow instructions come with each certificate we supply).
Created in 1977 by Ron Rivest, Adi Shamir, and Leonard Adleman, RSA is a highly secure cryptography method using a two-part key. The private key is kept by the owner to decrypt data; the public key to encrypt data is published. See more about encryption methods here.