What is bandwidth ?
Bandwidth ( or Data Transfer ) The web hosting service is the amount of traffic the website for a period of one month (starting from the first day of every month), the total bandwidth to use website, email and FTP both inbound and outbound. For Web hosting company Triple Systems Co. is a unit of bandwidth, such as GB package etc. Hosting-1 = 1GB.
And bandwidth in web hosting services are not related to the speed of opening web pages or send and receive email all.
Bandwidth usage examples
- Including email messages and attached files of 1MB = 1 the use of bandwidth 1MB.
- Including email messages and attached files of 1MB = 50 edition of the bandwidth 1 * 50MB (= 50MB).
What is SSL ?
Security and Secure Socket Layer (SSL) is a protocol for managing the security of Internet-based communication system. Data between the client and the server. Normally, the data is sent to the data is not encrypted in any way. The information is easily intercepted. It is a system that uses SSL to send data from the client to the server are encrypted before it is sent to the server that makes data transfer more secure.
SSL was developed by Netscape Communications began To use the application level protocol is Hypertext Transfer Protocol (HTTP) provides secure communication over the Web. Developed in the early electronic trade. Which is gaining increasing popularity in the Internet world.
The SSL encryption feature has two modes
- 40 bits encryption
- 128 bits encryption
The encoding of the two is used only in the United States. The principle of operation of SSL is an encrypted data to the client. The web browser will be encrypted. The web browser will be encrypted with Public Key Master Key from the server to the browser created. Then use these keys to encrypt data sent to the server. The encrypted data is then sent to the server. To decode it back to normal as paying through a credit card through the VISA and Master Card cards of all banks by the buyer does not have to notify the bank in advance on request. The service is integrated directly connected to the bank. Prior Information Server to access the bank has had to go through security before entering the bank. 40 bits of data code
SSL protocol allows to choose a method of encryption. How to create a digest and digital signature freely before communication begins to meet the needs of both Web servers and browsers. For added flexibility of use. The opportunity to try out new ways of encoding methods. Including reducing the export of encryption methods to countries that do not allow them.
Netscape developed the SSL version is version 2.0 and version 3.0, which supports the safer side. And a final version before standardized protocols on the Internet. By renamed as Transport Layer Security, or TLS standard care by Internet Engineering Task Force (IETF).
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The process to initiate communication through the SSL
Divided into 4 steps:
Step 1 announced a set of encryption methods. Digest and digital signature support of both the client and server.
Default messaging client and server communication (Hello message), which includes the version of the protocol. How to encrypt the Web server and client support. Communication identifier (Session identifier), including compression methods to communicate information that supports a specific communication to happen is for checking the connection between client and server. If there is a connection previously happened. Shows that have already been agreed communication methods. Can begin sending data immediately. This shortens the communication down.
Step 2 authentication server to the client
Next, the Web server sends the Certificate or confirmation of the identity of the server. Client Certificate authentication service with the Certificate Authority that was set. To confirm the validity of the Certificate Server.
Step 3 authentication of the client to the server (if necessary)
Certificate can be requested from the server to the client to determine the validity of the Client as was the case with the limited specialized applications that require only SSL client authentication support from both the server and client. Depending on the selected applications in communication, as it happens.
Step 4 client and server agreed set of encryption methods, creating digest and the use of digital signatures
Step examination Certificate requests from the client to the server are optional. Depending on the settings on the server. After the investigation is completed. Server and the client will agree to use the same encryption method using. The announcement of the first steps.
How to exchange encryption keys (Key Exchange Method) is to set up a mechanism to exchange keys used to encrypt the communication. Both the client and the server uses this key to encrypt and decrypt data in SSL version 2.0 will support RSA key exchange algorithm of SSL version 3.0 and higher support in other ways. More like using RSA with the Certificate or Diffie-Hellman and so on.
Encryption methods currently divided into 2 ways
1. Using the same key for encryption and decryption. This may be the key to the Session Key or Secret Key.
2. To use a different key for encoding and decoding. Comprising a public key and a private key, which is always matched. With any encryption keys Must be decoded with a key pair, and conversely only. Usually by means of A different encryption key used to encrypt the Session Key and sends it to the opposite side before communication will occur collectively, ways. In exchange encryption keys
SSL uses a symmetric key encryption algorithm or a single key for encryption and decryption. As discussed above, How is encryption Encrypted with DES and 3DES (Data Encryption Standard), an encryption method with the IDEA of RC2 and RC4 is an encryption algorithm of RSA, including how encryption Fortezza for the length of the encryption used is 40 bit, 96 bit and 128 bit
To track Message Authentication Code (MAC) to confirm the accuracy of the information, communications and defense. The false data The function creates a digest and select the SSL support is currently available in 128-bit MD5 and SHA-1 (Secure Hash Algorithm) with 160-bit, which means that both parties can support, and the right which is the last step. Communications are encrypted before it begins.
The security of the computer system or computer network is to realize a more compelling today. Because in today's world is a world of information. Keeping information secure is important to the individual and the organization. Therefore, to allow any individual to access information is what to watch because some of the individuals and organizations are important and can not be disclosed to third party
Authentication is so important because the person to login. It must be recognized that actually allowed. The first step is to examine the evidence before allowing login. Verification means that even very sophisticated data security have increased.
How to Select SSL
SSL is able to distinguish the three major items are as follows.
Initially, each SSL can work. Data encryption is the same for all but one thing that makes the price difference is that Brand because SSL is related to its credibility so as Verisign Brand, the brand has been the most popular. It's always been reliable. From website visitors and the result of Verisign's SSL in a higher price than other SSL brands.
2. Encryption Technology
Each SSL even under the same brand, but if that work with different technologies. It is priced differently. Which by all SSL with higher prices. It is packed with sophisticated encryption technology, such as Verisign Secure Site Pro True 128 Bit encryption technology will be more complex than conventional Verisign Secure Site, which will make the data more secure.
3. Extended Validation
Furthermore, the difference in the first and second, there are the so-called EV (Extended Validation), which is designed to check the existence of that order SSL in order to display the green and enables visitors to the site with the utmost confidence, SSL with EV category, it will cost more.
So how to choose the appropriate SSL can be either three reasons for this is primarily to use as your website to use SSL as a bank or business that needs a lot of credibility. Verisign in the type of visitors to the site with EV with probably the best choice. But if your site to use SSL as web pages within a company can be a Web Based Email internal use SSL123 will be sufficient.