There are several basic types of Internet connections:
The speed of your connection is usually measured in Kbps or Mbps. Kbps stands for kilobits per second (thousands of bits per second) and is a measure of bandwidth (the amount of data that can flow in a given time) on a data transmission medium. Higher bandwidths are more conveniently expressed in megabits per second (Mbps, or millions of bits per second) and in gigabits per second (Gbps, or billions of bits per second).
Direct full-time connections usually use the T-carrier system, introduced by the Bell System in the U.S. in the 1960s. This was the first successful system that supported digitized voice transmission. The original transmission rate (1.544 Mbps) in the T-1 line is in common use today by Internet service providers (ISPs) and private company connections to the Internet. Another level, the T-3 line, providing 44.736 Mbps, is also commonly used by ISPs.
There are various speeds and technologies from which you can connect to the Internet from your house (depending where you live and sometimes on how much you want to pay). Here are some of the home connection technologies.
V.90 is a standard, approved by the International Telecommunications Union (ITU), for transmitting data downstream to modems at 56 Kbps (thousand bits per second). The V.90 standard was arrived at by combining the x2 technology from US Robotics (now part of 3Com) and the K56flex technology from Rockwell. Transmission upstream from a computer modem is slower than downstream (about 33 Kbps) since it requires digital-to-analog conversion.
56 Kbps transmission technologies exploit the fact that most telephone company offices are interconnected with digital lines. Assuming your Internet connection provider has a digital connection to its telephone company office, the downstream traffic from your local Internet access provider can use a new transmission technique on your regular twisted-pair phone line that bypasses the usual digital-to-analog conversion. A V.90 modem doesn't need to demodulate the downstream data. Instead, it decodes a stream of multi-bit voltage pulses generated as though the line was equipped for digital information.
Integrated Services Digital Network (ISDN) is a set of CCITT/ITU standards for digital transmission over ordinary telephone copper wire as well as over other media. Home and business users who install ISDN adapters (in place of their modems) can see highly-graphic Web pages arriving very quickly (up to 128 Kbps). ISDN requires adapters at both ends of the transmission so your access provider also needs an ISDN adapter. ISDN is generally available from your phone company in most urban areas in the United States and Europe.
DSL (Digital Subscriber Line) is a technology for bringing high-bandwidth information to homes and small businesses over ordinary copper telephone lines. xDSL refers to different variations of DSL, such as ADSL, HDSL, and RADSL. Assuming your home or small business is close enough to a telephone company central office that offers DSL service, you may soon be able to receive data at rates up to 6.1 Mbps (of a theoretical 8.448 Mbps), enabling continuous transmission of motion video, audio, and even 3-D effects. More typically, individual connections will provide either 512 Kbps or 1 Mbps. During 1998 and 1999, DSL is being installed in a number of communities in the U.S. and elsewhere. Compaq, Intel, and Microsoft are among companies working with manufacturers to accelerate deployment of an easier-to-install form of DSL called "DSL Lite." Within a few years, DSL is expected to replace ISDN in many areas and to compete with the cable modem in bringing multimedia and 3-D to homes and small businesses.
ADSL (Asymmetric Digital Subscriber Line) is probably the most popular variation and allows transmitting digital information at high speeds on existing copper phone lines to homes and businesses. ADSL is asymmetric in that it uses most of the channel to transmit downstream to the user and only a small part to receive information from the user. ADSL simultaneously accommodates POTS (plain old telephone service). ADSL can transmit data at speeds ranging from 1.544 Mbps to 8 Mbps.
A cable modem is a device that enables you to hook up your PC to a local cable TV line and receive data at about 1.5 Mbps. This data rate far exceeds that of the prevalent 28.8 and 56 Kbps telephone modems and the up to 128 Kbps of ISDN and is about the data rate available to subscribers of Digital Subscriber Line (DSL) telephone service. A cable modem can be added to or integrated with a set top box that turns your TV set into an Internet channel. For PC attachment, the cable line must be split so that part of the line goes to the TV set and the other part goes to the cable modem and the PC.
A cable modem is really more like a network interface card (NIC) than a computer modem. All of the cable modems attached to a cable TV company coaxial cable line communicate with a Cable Modem Termination System (CMTS) at the local cable TV company office. All cable modems can receive from and send signals to only to the CMTS, but not to other cable modems on the line.
The actual bandwidth for Internet service over a cable TV line is up to 27 Mbps on the download path to the subscriber with about 2.5 Mbps of bandwidth for interactive responses in the other direction.
This is a fiber to the premises telecommunications service first offered by Verizon. It is what is called a Passive Optical Network (PON) configuration in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises, typically 32. A PON consists of an Optical Line Termination (OLT) at the communication company's office and a number of Optical Network Units (ONUs) near end users. It is, in other words, a point-to-multipoint configuration, which reduces the amount of fiber required compared with point to point. Depending on how much you want to pay, there are various speed configurations such as 5 Mbps Downstream/2 Mbps Up, 15 Mbps Downstream/2 Mbps Up, and 30 Mbps Downstream/5 Mbps Up.
Often termed Wi-Fi is a set of product compatibility standards for wireless
local area networks (WLAN) based on the IEEE 802.11 specifications. New
standards beyond the 802.11 specifications offer many enhancements, anywhere
from longer range to greater transfer speeds. The speed for Wi-Fi depends on the
specification being used. This can be into the range of 100 Mbps while moving
and 1 Gbps while still.
Wi-Fi was intended to be used for mobile devices and LANs, but is now often used for Internet access. It enables a person with a wireless-enabled computer, tablet, netbook, phone, etc. to connect to the Internet when in proximity of an access point. The geographical region covered by one or several access points is called a hotspot. While commercial services attempt to move existing business models to Wi-Fi, many groups, communities, cities, and individuals have set up free Wi-Fi networks, often adopting a common peering agreement in order that networks can openly share with each other. At one point, free wireless mesh networks were considered the future of the internet. The problem is that free networks become a haven for criminal activity.
There are a number of sites that allow you to test how fast your Internet connections. To find out how fast your connection is, follow this link to broadband reports, pick one of the speed tests, and run the test.
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