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Internet Business Foundations © 2004 ProsoftTraining All rights reserved Lesson 2: Web Browsing Objectives Identify the basic functions of Web browsers Install a Web browser Identify the components of Web addresses Use browsers to authenticate and encrypt Identify considerations in selecting a browser Identify and locate resources for technical data Identify how businesses use browsers Use various browsing techniques Configure Web browser preferences Define and use cookies Configure browser security settings Identify the function of proxy servers Troubleshoot common Internet client problems Basic Functions of Web Browsers Provide a way for users to access and navigate Web pages Display Web pages properly Provide technology to enable multimedia features Provide access to Internet services (such as FTP, Telnet, news servers and e-mail) Perform authentication and encryption functions Installing a Web Browser Microsoft Internet Explorer 6.0 is packaged with Windows XP Professional Most browser software is available on the Web or through a vendor CD ISPs provide browser software on installation CDROMs You should install the latest version of a browser because it will have the most recent security features Look for and install browser updates as they become available Web Addresses Every Web page has a unique address called a URL URLs typically include the protocol, the Internet resource (server or host name) and the domain name You enter absolute URLs into your browser’s Address or Location box Relative URLs can be used for coding Web sites How Browsers Work 1. 2. 3. 4. 5. 6. 7. 8. You enter a URL into the browser Browser breaks the URL into three parts: protocol, server and domain name, and file name Browser contacts a domain name server to translate server name into an IP address Browser uses IP address to connect to server Browser uses HTTP to request a page from the server Some level of authentication takes place Server sends the requested page (coded in HTML) to the browser Browser reads and interprets the HTML and displays the Web page Authentication Authentication – the process of verifying the identity of a user who logs on to a system, or the integrity of transmitted data General authentication types: • Anonymous logon – no user name or password is required and authentication is handled transparently by the browser and server • Basic authentication – a user name and password are required, and that information is sent as plain text • Secure authentication – a user name and password are required, and they are encrypted before being sent across the Internet • Digital certificates – you must have the proper digital certificate to gain access Encryption Encryption – the process of converting data into an unreadable form of text Decryption – the process of converting the encrypted data back to its original form Encryption and decryption are performed using keys Key – a mathematical algorithm The more complex the encryption algorithm, the harder it is to decipher the encrypted message without access to the key Authentication protocols Password Authentication Protocol (PAP) – used to authenticate dial-up sessions for remote users Challenge Handshake Authentication Protocol (CHAP) – authenticates through a server sending a challenge phrase to a client and comparing the client response (generated through a one-way hash function) with its own calculation of the expected hash value Microsoft Challenge Handshake Authentication Protocol (MS-CHAP) – a proprietary version of CHAP used by servers running IIS SSL and TLS Secure Sockets Layer (SSL) – a protocol for secure exchanges • authenticates using digital certificates • provides for data encryption Transport Layer Security (TLS) – successor to SSL • becoming more common • based on SSL 3.0 • provides for encryption and authentication Secure Protocols Various protocols in the TCP/IP suite can be made secure by running them over SSL/TLS, including: • HTTPS • S/FTP • IMAP/S • POP3S Browser Choices Most popular browsers in use today are Microsoft Internet Explorer and Netscape Navigator Alternative browsers include: • Mozilla • Opera • Konqueror • Lynx • Arachne Resources for Technical Data The following Web sites are among the many you can visit for technical data: • www.netcraft.com • www.whatis.com • www.howstuffworks.com • www.learnthenet.com • www.microsoft.com/technet Business Uses of Browsers intranet – an internal or in-house Web site used only by employees within a company extranet – an internal network designed to provide access to selected external users; is not available to the Internet public Webinars and Web conferences – online training or conference sessions that utilize Internet technology to provide interactive and presentation elements to users Browsing Techniques Techniques available to make your browsing sessions more efficient: • Using Bookmarks and Favorites • Using multiple windows • Following links Configuring Browser Preferences Browser preferences you can configure to suit your working style include: • Browser fonts • Home page • History folder • Controlling pop-up and pop-under windows • Browser cache settings • Image loading • Cookie handling • Cookie warnings Configuring Browser Security You can configure your browser’s security settings to accept, reject or prompt before accepting: • ActiveX controls • Java applets To restrict these items in Internet Explorer, set safety levels accordingly Proxy Servers Proxy servers come between corporate networks and the Internet Proxy servers can provide the following services: • Web document caching • Corporate firewall access Browsers must be properly configured to work with proxy servers Netscape Navigator can be manually configured to work with a proxy server, or can use a proxy server’s URL to automatically configure itself Internet Explorer can automatically scan the network for a proxy server; it can also use a configuration script; or you can configure it manually Troubleshooting Internet Client Problems By adjusting browser functions and settings, you can troubleshoot the following client problems: • Poor rendering • Slow connection • No connection • Inability to render images • Slow browser and other system functions