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Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Third Edition The Internet Chapter 25 © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Overview Third Edition • In this chapter, you will learn how to – Explain how the Internet works – Connect to the Internet – Use Internet software tools © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Internet Tiers Third Edition • Tier 1 (main tier) – Seven to twelve companies – Own long-distance, high-speed fiber-optic networks called backbones – Interconnect at network access points (NAPs) in major cities across the globe © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Internet Tiers (continued) Third Edition • Tier 2 – Smaller regional networks – Larger ISPs that provide Internet access are often Tier 2 providers • Tier 3 – Even more regional networks • Built-in redundancy – Decentralized – Can easily adapt to failures on network © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs TCP/IP: Language of the Internet Third Edition • TCP/IP is the common language of the Internet – Suite of protocols – Many services—such as HTTP—plus the capability to create new services • This vast routed network, running TCP/IP is the Internet • How do we tap into it? © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Internet Service Providers Third Edition • Internet service providers (ISPs) gain access to the Internet from leased Tier 1 and Tier 2 connections • Users gain access to the Internet by leasing connections from ISPs • ISPs come in many sizes – National companies – Local shops © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Connection Concepts Third Edition • Connecting to an ISP requires – Hardware for connectivity • Modem and working phone line • DSL or cable modem • Some other high-speed connection – Software (protocols) • Governs the connection and data flow – Software (services) • E-mail, browsing © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Many Ways to Connect Third Edition • Dial-up – Analog – ISDN • Dedicated – DSL – Cable – Fiber – LAN © 2010 The McGraw-Hill Companies, Inc. All rights reserved • Wireless – Wi-Fi – Cellular • Satellite Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Dial-up Requires a Modem Third Edition • The term modem is an abbreviation for modulator/demodulator – Enables computers to communicate with each other via standard telephone lines – Converts analog signals into digital signals – Converts digital signals into analog signals © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Modems Third Edition • A modem uses serial communication – Transmits data as a series of individual 1s and 0s • Universal asynchronous receiver/transmitter (UART) – Converts serial into 8-bit parallel data © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Baud Rate Third Edition • Baud rate is the basic cycle of time that a modem uses as its carrier frequency – Maximum baud rate of a phone line is 2400 baud • The modem speed is measured in bits per second (bps) – Modems can pack multiple bits into a single baud – 14 bits × 2400 baud = speed of 33.6 Kbps © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Communication Standards Third Edition • Modern modem standards are referred to as V standards – Set by the International Telecommunication Union—Telecommunications Standardization Sector (ITU-T) – Both standards offer download speeds of just under 56 Kbps • V.90 upload speeds of up 33.6 Kbps • V.92 upload speeds of up to 48 Kbps • Rarely get download speeds greater than 48 Kbps © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Modem Connections Third Edition • Modems connect to the PC in one of two ways – Internal modems connect to a PCI or PCI Express expansion slot – External modems connect through a serial port or USB port © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Dial-up Networking Third Edition • Dial-up networking – Uses information from your ISP • The dial-up phone number, user name, password, and other special configuration parameters – Configured in Network and Internet Connections option in Windows XP • Select Set up or change your Internet connection and use the wizard – Configured in the Network and Sharing Center in Vista • Set up a connection or network © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Dial-up Networking (continued) Third Edition • Uses PPP protocol – Point-to-point protocol (PPP) – Streaming protocol developed especially for dial-up Internet access • Most dial-up errors are user errors – Turn the volume up and verify the connection – Listen for a dial tone – Listen for “modem talk” instead of a person answering the phone © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs ISDN Third Edition • Integrated Services Digital Network (ISDN) – Phone companies have upgraded their network infrastructures to all digital lines (except for the line from your phone to the central office) – ISDN goes fully digital – Uses channels • B (Bearer) used for data and voice at 64 Kbps • D (Delta) used for setup and configuration information at 16 Kbps • Basic Rate Interface (BRI) – Most common setup – Two B (total of 128 Kbps) and one D channel – ISDN uses terminal adapters rather than modems © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs DSL Third Edition • Digital subscriber line (DSL) – Uses a regular phone line but special equipment at both ends – Much faster than dial-up • Upload: 128-384 Kbps • Download: 2-6 Mbps or greater – Installation requires a NIC and DSL receiver (often called a DSL modem) – Must be within 18,000 feet from the closest main phone service switching center © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Cable Third Edition • Uses cable TV connections – Connect the RG-6 or RG-59 coaxial cable to a cable modem – Connect modem to a NIC in the PC with UTP cable • Very fast speeds—often much faster than DSL (20+ Mbps download) • Bandwidth is shared with other users, which can affect performance © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Fiber Third Edition • FiOS from Verizon – Fiber direct to the home – Download speeds vary from 5 Mbps down/2 Mbps up to 50 Mbps down/20 Mbps up – Average is 15 Mbps down/5 Mbps up • U-verse from AT&T – Mix of fiber and local copper at the house – Average download of 3-6 Mbps down/1 Mbps up, with 24 Mbps down possible © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Other Internet Connections Third Edition • LANs – Most companies connect their network to the Internet through an ISP – Users connect through the LAN • Wireless – Wireless connections require access via wired network – If wired network has access, wireless devices can use this wired network via a WAP • Satellite – Uploads previously done through modem – Initial connections still must be made through a modem © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Internet Connection Sharing Third Edition • Internet connection sharing (ICS) – Allows one computer to share a single Internet connection with multiple devices – Available since Windows 98 SE – Requires a LAN between the devices © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Hardware Connection Sharing Third Edition • SOHO routers like this WRT54G are very popular hardware connections between your network and the ISP • Provide hardware firewall protection • Built-in WAP • Built-in switch © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Network Address Translation (NAT) Third Edition • NAT enables multiple devices to share a single Internet address • Most ISPs provide a single Internet address – Without routers that supported NAT, you would have to purchase separate IP addresses for every device that needed Internet access – Alternatively you could use your own IP addresses, but only if you didn’t connect to the Internet • NAT = GOOD! © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Basic Router Configuration Third Edition • All routers have an administrative user name/password that enables you to configure the router • Change from the default © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs DHCP or Not DHCP Third Edition • All home routers are DHCP servers by default • You should only have one DHCP server • Disable DHCP if you already have a DHCP server © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Set the WAN Address Third Edition • WAN addresses can be static or dynamic • If you’re allocated a static IP address, update your WAN connection per ISP instruction © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Updating Firmware Third Edition • SOHO routers often have firmware updates – check with the manufacturer © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Internet Software Tools Third Edition • Once you’ve made the connection to the Internet, you can now use the thousands of Internet applications • CompTIA wants you to know about the following applications – – – – – – World Wide Web (HTTP and HTTPS) E-mail (POP and SMTP) Newsgroups FTP Telnet VoIP © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs TCP/IP Ports Third Edition • Every Internet application is assigned one or more TCP/IP port number(s) – 1-65536 • The first 1024 port numbers are reserved for the most popular and common applications © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs World Wide Web Third Edition • The World Wide Web (Web) provides a graphical face for the Internet – Web servers house Web sites – Web browsers access the files on Web servers • Web browsers are highly configurable – A proxy server enables multiple connections to the Internet to go through one protected PC – Similar to ICS, but more sophisticated • Typically used in corporate connections • Uses Layer 7 – browsers communicate directly with the proxy server software when desiring a Web site © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Proxy Server Third Edition • A proxy server is a device or software that acts as an intermediary between Internet servers and clients • Commonly used to filter Internet access • Clients must be configured to use a proxy server © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs World Wide Web Third Edition • Security and scripts – Active programs and scripts such as Java and Active Server Pages • Can be useful and powerful • Can be malicious – Internet Explorer has configurable options • Tools | Internet Options| Security tab lets you set security levels © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs HTTP vs. HTTPS Third Edition • HTTP provides no encryption • HTTP over Secure Sockets Layer (HTTPS) – Provides encryption – Use when submitting personal information such as credit card numbers, phone numbers, etc. – Verify HTTPS is being used two ways • Lock icon • HTTPS appears in address bar © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs E-mail Third Edition • Popular e-mail programs – Microsoft Outlook – Mozilla Thunderbird • E-mail protocols – Post Office Protocol version 3 (POP3) • Used for receiving e-mail – Internet Message Access Protocol (IMAP) • Used for receiving mail, but with more features than POP3 – Simple Mail Transfer Protocol (SMTP) • Used for sending e-mail © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs E-mail (continued) Third Edition • Configuring e-mail – Can use name or IP © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Web Mail Third Edition • Available anywhere you have Internet access • Free, but requires some sort of connection • Most services offer lots of storage, searchable messages, flagging of messages for follow-up, etc. • Most popular – Gmail – Hotmail – Yahoo! Mail © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs E-mail Security Third Edition • Digital signatures confirm identity of sender of e-mail • Concepts are simple, implementations not so much – Requires that you get a certificate from an issuing authority (same folks who create certificates for secure e-commerce) • Try Thawte’s Personal e-mail certificates • http://www.thawte.com/resources/personal-emailcertificates/index.html – Then must add to e-mail application • Easy in Outlook, barely possible in Web mail © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Newsgroups Third Edition • Use a newsreader program to access newsgroups – Outlook Express was common newsreader (free) – News servers run Network News Transfer Protocol (NNTP) – Get NNTP address from ISP © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs FTP Third Edition • File Transfer Protocol (FTP) – Used to share files – Address usually ftp.[whatever].com – Requires an FTP server on one end and an FTP client on the other • WS_FTP is a popular client • Some Web browsers also support FTP – Public FTP servers allow anonymous login • User Name: Anonymous • Password: e-mail address • Sends user name and password in clear text © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Telnet and SSH Third Edition • Text-based terminal emulation programs for controlling a remote computer • They look the same but – Telnet is unencrypted – SSH is encrypted © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs VoIP Third Edition • Voice over IP (VoIP) – Enables voice calls over the network – Works with any type of high-speed connection • DSL, cable, satellite, etc. – VoIP is a collection of protocols • Not a single protocol – Vendors • Skype • Vonage © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Terminal Emulation Third Edition • Enables access to other computers as if you were there • Windows Remote Desktop • University of Cambridge’s VNC – Free and totally cross-platform – Can run and control Windows from a Macintosh system and vice versa © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Terminal Emulation (continued) Third Edition • Remote Desktop – Microsoft’s implementation – Free and built into system © 2010 The McGraw-Hill Companies, Inc. All rights reserved • Remote Assistance – End user requests help – Helper can take control of desktop • If permission granted Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Remote Desktop Third Edition • Remote Desktop enables you to access computers over the network • Excellent tool for managing headless servers • Here’s how to get there – Start | Run or Start Search | mstsc – Start | All Programs | Accessories | Communications | Remote Desktop © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Virtual Private Networks (VPN) Third Edition • Allows you to connect to a private network via the Internet © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Beyond A+ Third Edition • Online gaming – World of Warcraft (WoW) – Counter-Strike • Chat – Internet Relay Chat (IRC) © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Beyond A+ Third Edition • File sharing – Allows users to share files with other users – Users can access any shared files (such as MP3s) on any computer anywhere on the Internet – Napster and Kazaa are file-sharing programs • Music industry trying to stop file sharing • BitTorrent protocol to counter music industry – Also used for Linux distributions – µTorrent is one program using BitTorrent protocol © 2010 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to Managing and Troubleshooting PCs Third Edition © 2010 The McGraw-Hill Companies, Inc. All rights reserved