data communication part 11
TRANSCRIPT
Data CommunicationPart 11
INTERNETINFORMATION SERVICES (IIS)
◎ IIS enables you to set a maximum connection limit on your Web server based on available bandwidth and memory.
◎ This enables you to protect your network against an overwhelming number of requests due to a particularly popular page or a type of malicious attack called a denial of service(DoS) attack.
APACHE◎ UNIX/Linux-based operating systems runApache HTTP
Server.
◎ Apache serves well over 50 percent of the Web sites on the Internet. Apache is incredibly popular, runs on multiple operating systems
◎ (including Windows), and, best of all, is free!
◎ Apache is nothing more than an executable program and a bunch of text files, so it isn’t much to look at.
◎ To ease configuration, most Web administrators use add-on graphical user interfaces (GUIs) such as Webmin that make administering Apache a breeze
WEBMIN
WEB CLIENTS
◎ programs used to surf the Web.
◎ A client program (a Web browser) reads Web pages supplied by the Web server. r
◎ Web browsers are Microsoft Internet Explorer, Mozilla Firefox, Apple, Safari, Opera, and Google Chrome.
SECURE SOCKETS LAYER AND HTTPS
◎ HTTP is not a secure protocol
◎ SSL - Secure Sockets Layer (SSL) .
◎ SSL is a protocol developed by Netscape for transmitting private documents over the Internet.
◎ SSL works by using a public key to encrypt sensitive data. This encrypted data is sent over an SSL connection, and then decrypted at the receiving end using a private
◎ key. All the popular Web browsers and Web servers support SSL, and many Web sites use the protocol to obtain confidential user information, such as credit card numbers.
◎ HTTPS stands for Hypertext Transfer Protocol over SSL.
◎ HTTPS uses TCP port 443.
TELNET
◎ Operating systems didn’t have windows and pretty icons.
◎ The interface to the mainframe was a command line
◎ Connect remotely to another computer via the command line
◎ Telnet is rarely used on the Internet and has been replaced with Secure Shell (SSH) , a terminal emulation program that looks exactly like Telnet but encrypts the data.
TELNET SERVERS AND CLIENTS
◎ The oldest Telnet server, found on UNIX and Linux systems, is the venerable telnetd.
◎ A Telnet client is the computer from which you log onto the remote
◎ server. Most operating systems have a built-in Telnet client that you run on a command prompt.