Dial-up Networking in Software

Paint Quick Response Code in Software Dial-up Networking

The software side of dial-up networks requires configuration within Figure 2213 A CNR modem Windows to include information provided by your ISP The ISP provides a dial-up telephone number or numbers, as well as your user name and initial password In adCross Check dition, the ISP will tell you about any special configuration options Installing a PCI Modem you need to specify in the software Installing a PCI modem card involves pretty much the same process as setup The full configuration of installing any other PCI card Refer to 6, Expansion Bus, and dial-up networking is beyond the cross check your knowledge of the process scope of this book, but you should at least know where to go to follow 1 What do you need to guard against when installing a PCI card instructions from your ISP Let s 2 Any issues involving drivers, plug and play, or other hardware take a look at the Network and topics Internet Connections applet in Windows XP

Network Connections To start configuring a dial-up connection in Windows XP, open the Control Panel Select Network and Internet Connections from the Pick a category menu (Figure 2215), and then choose Set up or change your Internet connection from the Pick a task menu (Figure 2216) The Internet Properties dialog box opens with the Connections tab displayed All your work will proceed from here (Figure 2217) Click the Setup button to run the New Connection Wizard, and then work through the screens (Figure 2218) At this point, you re going to need information provided by your ISP to configure your connection properly When you finish the configuration, you ll see a new Connect To option on the Start menu if your system is set up that way If not, open up Network Connections

and your new dial-up connection will be available Figure 2219 shows the option to connect to a fictitious ISP, Cool-Ridescom PPP Dial-up links to the Internet have their own special hardware protocol called Point-to-Point Protocol (PPP) PPP is a streaming protocol developed especially for dial-up Internet access To Windows, a modem is nothing more than a special type of network adapter Modems will have their own configuration entry in the Network Connections applet Most dial-up I can t connect to the Internet type problems are user errors Your first area of investigation is the modem itself Use the modem s properties to make sure the volume is turned up Have the user listen to the connection Does she hear a dial tone If she doesn t, make sure the modem s line is plugged into a good phone jack Does she hear the modem dial and then hear someone saying, Hello Hello If so, she probably dialed the wrong number! Wrong password error messages are fairly straightforward remember that the password may be correct, but the user name may be wrong If she still fails to connect, it s time to call the network folks to see what is not properly configured in the Dial-up Networking settings

A standard telephone connection comprises many pieces First, the phone line runs from your phone out to a network interface box (the little box on the side of your house), and into a central switch belonging to the telephone company (In some cases, intermediary steps are present) Standard metropolitan areas have a large number of central offices, each with a central switch Houston, Texas, for example, has nearly 100 offices in the general metro area These central switches connect to each other through highcapacity trunk lines Before 1970, the entire phone system was analog; over time, however, phone companies began to upgrade their trunk lines to digital systems Today, the entire telephone system, with the exception of the line from your phone to the central office, is digital During this upgrade period, customers continued to demand higher throughput from their phone lines The old telephone line was not expected to produce more than 288 Kbps (56 K modems, which were a big surprise to the phone companies, didn t appear until 1995) Needless to say, the phone companies were very motivated to come up with a way to generate higher capacities Their answer was actually fairly straightforward: make the entire phone system digital By adding special equipment at the central office and the user s location, phone companies can now achieve a throughput of up to 64 K per line (see the paragraphs following) over the same copper wires already used by telephone lines This process of sending telephone transmission across fully digital lines end-to-end is called integrated services digital network (ISDN) service ISDN service consists of two types of channels: Bearer, or B, channels and Delta, or D, channels B channels carry data and voice information at 64 Kbps D channels carry setup and configuration information and carry data at 16 Kbps Most providers of ISDN allow the user to choose either one or two B channels The more common setup is two B/one D, usually called a basic rate interface (BRI) setup A BRI setup uses only one physical line, but each B channel sends 64 K, doubling the throughput total to 128 K ISDN also connects much faster than modems, eliminating that long, annoying, mating call you get with phone modems The monthly cost per B channel is slightly more than a regular phone line, and usually a fairly steep initial fee is levied for the installation and equipment The big limitation is that you usually need to be within about 18,000 feet of a central office to use ISDN The physical connections for ISDN bear some similarity to analog modems An ISDN wall socket usually looks something like a standard RJ-45 network jack The most common interface for your computer is a device called a terminal adapter (TA) TAs look much like regular modems, and like modems, they come in external and internal variants You can even get TAs that are also hubs, enabling your system to support a direct LAN connection

Another type of ISDN, called a primary rate interface (PRI), is composed of twenty-three 64-Kbps B channels and one 64-Kbps D channel, giving it a total throughput of 15 megabits per second PRI ISDN lines are rarely used as dial-up connections they are far more common on dedicated lines

The two most common forms of DSL you ll find are asynchronous (ADSL) and synchronous (SDSL) ADSL lines differ between slow upload speed (such as 128, 256, or 384 Kbps) and faster download speed (usually 2 Mbps) SDSL has the same upload and download speeds, but telecom companies charge a lot more for the privilege DSL encompasses many such variations, so you ll often see it referred to as xDSL

Digital subscriber line (DSL) connections to ISPs use a standard telephone line but special equipment on each end to create always-on Internet connections at blindingly fast speeds, especially when compared with analog dial-up connections Service levels vary around the US, but the typical