The Windows 98 communications subsystem allows users to make simultaneous connections to a variety of communications services, including electronic mail and online services. With Windows 98, connecting to a communications service is as easy as connecting to your network.
Users need select and configure a modem only once for it to work with all applications created for Windows 98. You can install a modem in the Modems option in Control Panel, or in an application created for Windows 98—the first time the application is run.
Two other communications tools facilitate modem calling: HyperTerminal connects two computers over a modem or a serial connection and transfers files between them, and Phone Dialer dials voice telephone calls.
Windows 98 provides the basic protocols and utilities users need to connect a computer to a server that has access to the Internet, and the software they need to browse and download information from the Internet.
The Windows 98 communications subsystem allows applications to transmit data quickly and reliably, and to cooperatively share communications devices. The new kernel and new communications architecture in Windows 98 provide the following benefits.
High-speed reliability.
The data-transmission speed in Windows 98 is limited only by the hardware characteristics of the computer, such as the processor speed and the type of communications port. Windows 98 supports communications with devices of high transmission speeds, such as ISDN, which can communicate at speeds of 64 or 128 kilobits per second (Kbps).
High data throughput.
The 32-bit communications subsystem and preemptive multitasking architecture provide high data throughput and an instant response.
Support for Plug and Play and legacy communications devices.
Plug and Play support and device installation wizards, simplify installation and configuration of Plug and Play and legacy modems and communications devices.
Device sharing among communications applications.
The Telephony Application Programming Interface (TAPI) arbitrates among applications that want to share the same communications ports and devices.
This section contains a brief summary of the communications tools included in Windows 98. The tools are described in more detail later in this chapter.
Modem is short for modulator/demodulator. It is a communications tool that enables a computer to transmit information over a standard telephone line. Because a computer is digital (works with discrete electrical signals representing binary 1 and binary 0) and a telephone line is analog (carries a signal that can have any of a large number of variations), modems are required to convert digital to analog and vice versa.
You can use HyperTerminal with a modem to connect two computers so you can send and receive files or connect to computer bulletin boards and other information programs. For example, you can use HyperTerminal to connect to an online service and to download files from a bulletin board on the online service. You can also use HyperTerminal to connect a computer directly to another computer.
The Phone Dialer application lets you dial telephone numbers using the calling card and location information defined in Dialing Properties. It also stores frequently dialed numbers, dials stored telephone numbers, and logs telephone calls.
Dial-Up Networking provides remote users with complete network capabilities, including downloading and browsing electronic mail, accessing shared files, and running a client/server application. Dial-Up Networking lets you make a dial-up connection to remote networks, such as the Internet over a telephone or ISDN line.
Mobile computing features include Briefcase, which keeps documents up-to-date on two computers; Direct Cable Connection, which allows two computers to share resources when connected by a serial cable; and deferred printing capability, which lets you generate print jobs from a remote site and print them when you return to the office.
For more information about Dial-Up Networking, see Chapter 19, "Remote Networking and Mobile Computing."
Microsoft Outlook Express is a universal information client that can read and send electronic mail from any message application that supports MAPI services.
For more information about Outlook Express, see Chapter 22, "Electronic Mail with Outlook Express."
The Win32 communications APIs in Windows 98 provide an interface for using modems and communications devices. Applications call the Win32 communications APIs to configure modems and perform data I/O through them.
Windows TAPI provides a standard way for communications applications to control telephony functions for data, fax, and voice calls. The TAPI manages all signaling between a computer and a telephone network, including basic functions, such as dialing, answering, and hanging up a call. It also supports supplementary functions, such as hold, transfer, conference, and call park found in PBX, ISDN, and other telephone systems.
The universal modem driver (Unimodem) is a layer that provides services for data and fax modems and voice so that users and application developers will not have to learn or maintain difficult modem AT commands to dial, answer, and configure modems. Instead, Unimodem does these tasks automatically by using INF files supplied by modem hardware vendors.
Unimodem is both a VCOMM device driver and a TAPI Service Provider. Other Service Providers (for example, those supporting other devices, such as an ISDN adapter, a telephone on a PBX system, or an AT command modem) can also be used with TAPI.
Microsoft provides Integrated Services Digital Network (ISDN) for remote computing in Windows 98. ISDN, with speeds of up to 128 Kbps, offers higher bandwidth than modems over analog telephone lines. ISDN can be used over an existing telephone network and can provide connections to the Internet that support World Wide Web browsing, multimedia, and video presentation applications.
To use your modem with the built-in communications features of Windows 98, including HyperTerminal and Dial-Up Networking, you must configure your modem using the Modems option in Control Panel. Settings made in the Modems Properties dialog box do not affect modem operation in programs designed for MS-DOS or Windows version 3.1.