A cable modem is a type of device that provides access to a data signal sent over the cable television infrastructure. Cable modems are mainly used to deliver broadband Internet access in the form of cable Internet, using unused bandwidth on a cable television network. They are found in Australia, New Zealand, Canada, Europe, the United Kingdom, and the USA. In USA alone there are more than 22.5 million cable modem users but when it comes to seeing and selecting a cable modem there are many choices to choose from.
With the help of a modem you can also send and receive faxes using your PC, eliminating the need for a fax machine. As no major difference exists in the basic functionality between modems today, manufacturers have begun adding special features, such as the ability to send voice messages to other users while communicating online or to automatically differentiate between voice, fax, and data calls. Broadband Internet access methods, such as cable and DSL, need a different type of device. Cable and DSL "modems" do not work in the same way as the standard V.90 modem, and most of them need to be matched to the specific vendor offering the service. You can purchase a modem for DSL access, but unless it's the one specified by the DSL provider, it might not work. External modems need an available port to plug into, but they're easier to install and offer handy status lights. Internal modems require a free slot inside your PC, and are generally cheaper. If you use a laptop, you'll definitely want to choose a PC Card modem for maximum portability. Wireless modems are also available but then in regards to effective functioning it does not have much of a difference from the wired modems. The "best" cable modem would differ from one user to the other, therefore here are the specifications of each configuration and now you can certainly the "best" one for you.
The ADTRAN Express 3000 series is a family of ISDN modems that are ideal for remote access and corporate connectivity. The series is capable of transmitting data at speeds up to 230.4 kbps, when using hi/fn compression or up to 512 kbps when using Microsoft compression. They include both ISDN terminal adapter and network termination (NT1) functionality.Configuring the Express series is fast and simple. ADTRAN's patented Expert ISDN automatically detects the telephone company parameters such as Switch Type and SPID numbers. In areas where the telephone company automatically downloads this information to the modem, the units becomes plug-and-play with the ISDN line.The Express series supports two analog devices such as telephone, fax machine, or analog modem in addition to the computer connection for data transmissions on the Express 3000. When transmitting data at maximum throughput over both B channels using Multilink PPP, the unit automatically detects calls on the analog ports. Upon detection, the data speed is adjusted to 64 kbps using one B channel and accepts the analog/voice call, on the other B channel. Upon completion of the analog/voice call, the data automatically resumes transfer over both B channels.Remote configuration allows MIS managers the flexibility of adjusting the configuration of remote units over the ISDN line. The Express transmits data over an RS-232 interface and transfers synchronous data at rates from 2400 to 128 kbps (Express 3010 only) and asynchronous data at rates from 1200 bps to 230.4 kbps. At rates over 64 kbps, BONDing or MLPPP is used to synchronize the data across the two B channels. Configuration of the unit is achieved using a VT 100 interface or AT commands. Dialing is initiated in-band over the RS-232 interface using AT commands, V.25 bis or DTR assertion.
Wireless modem is a useful device that helps people to access Internet through a wireless network on your computer or electronic device, such as PDA. A wireless modem allows you to use your Internet-enabled device anywhere in your home.
Origin:sanbobo
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