What are the Wired Broadband Technologies?
What are the Wired Broadband Technologies?
Wired broadband essentially means there is a physical connection to a physical location (a home or business) through a cable. There are three main types of wired broadband connections for consumer or residential use: DSL, coaxial cable, and fiber. DSL uses traditional copper wire telephone lines. Cable television companies traditionally provide service over coaxial cables. Fiber systems are comprised of glass fiber strands over which optical (light) signals are sent. (Other options for wired broadband include T1 or T3 lines and Broadband over Power Lines (BPL)). With the use of a router, all wired technologies can also provide a Wi-Fi network within the home or business.
DSL is a wired transmission that uses traditional copper telephone lines already installed to homes and businesses. Availability and speed of DSL service may depend on the distance from a home or business to the closest broadband-equipped telephone company central office or telephone exchange.
A modem in your home connects the computer or wireless router to a copper telephone line using an Ethernet cable. The phone line connects to a digital subscriber line access multiplexer (DSLAM) at the telephone central office or, in some instances, at a remotely located junction box in outlying neighborhoods. The DSLAM, combines multiple signals into one aggregate connection and routes it to the ISPs Internet backbone.
An advantage of DSL service is that it works with existing wiring. The only equipment needed is a modem plugged into an existing phone jack and filters for each telephone in your home or office. Another benefit of DSL service is that each user has a dedicated link and the speed is constant and will not diminish if more people in your neighborhood are also using DSL. DSL provides reliable broadband service for most residential and small business customers.
A disadvantage of DSL service is the inability to deliver the service further than 18,000 feet from the central phone office or other DSLAM location. DSL cannot be reliably delivered to homes or businesses beyond this distance. Another disadvantage is that the upload speeds do not match download speeds. While DSL connections are adequate for the average consumer, with technology enhancements and innovation, the bandwidth that DSL offers may be outdated for many due to its bandwidth constraints.
Cable television companies provide broadband using the same coaxial cables that deliver pictures and sound to your TV set. A cable modem is an external device that normally has two connections: one to the cable wall outlet, the other to a computer. Cable Internet is usually faster than DSL.
Subscribers can access their cable modem service by simply turning on their computers, without dialing-up an ISP which is referred to as an “always on” connection. You can still watch cable TV while using broadband and get telephone service through Voice over Internet Protocol (VoIP) phone technology. Cable provider’s market their services in bundles, which can be a cost effective way to purchase internet services. While cable broadband is faster than DSL, transmission speeds vary depending on the type of modem, cable network, and how many people in the neighborhood are using a cable connection.
A benefit of cable modem service is its availability to all cable company customers where the cable network has been upgraded to deliver cable modem service. The distance between your residence and the cable company will not affect your Internet speed. Cable is also generally faster than DSL.
A disadvantage of cable modem service for rural communities is the lack of cable service beyond the edges of the larger towns. Another disadvantage is that the connection is shared between you and other people on the network segment and therefore speed may vary greatly at different times of the day and can slow down significantly in a neighborhood where many residents using cable connections access the Internet simultaneously. For example, if you live in a neighborhood where cable modem penetration is high you may notice a significant increase in the time it takes to upload and download information in the evening when people return home from work and school. Another disadvantage is that upload speeds never match download speeds.
Fiber optic technology converts electrical signals to light pulses (on/off) and sends the light pulses through transparent glass fibers about the diameter of a human hair. There is less signal loss or degradation with fiber optic technology than conventional copper wires or coaxial cables. Fiber transmits data at speeds far exceeding current DSL or cable modem speeds.
There are advantages to using fiber optic cable for telecommunications; the main advantage is the ability to provide higher bandwidth and greater distance between terminals. Compared to conventional copper wire, fiber optic cable can deliver more bandwidth than conventional metal wire. Because of its size, many optical fibers can be bundled into one outer covering, or jacket, allowing for a higher carrying capacity—more phone or cable lines going through one channel. Fiber optic cable can deliver more bandwidth than other broadband technologies at a lower cost of maintenance and allows for future expansion and opportunities as innovative and entrepreneurial concepts evolve.
Installing fiber and lighting the fiber cable is expensive and maybe cost-prohibitive for many providers serving rural areas. Fiber cable is fragile and also requires equipment to convert electrical signals into light signals and then reconvert them back into an electrical signal at the receiving end.
Broadband over Power Lines
BPL is the delivery of broadband over the existing low- and medium-voltage electric power distribution network. BPL speeds are comparable to DSL and cable modem speeds. BPL can be provided to homes using existing electrical connections and outlets.
Broadband over Power Lines: Advantages
BPL can use existing power lines decreasing the cost of installing a new transport infrastructure and the ability to connect a modem to any electric receptacle. BPL also sends and receives data at the same high speed. You can upload mail, video files, and business data as quickly as you can download similar files.
Broadband over Power Lines: Disadvantages
A major hurdle for BPL in rural areas is the cost of equipping the power lines to carry the broadband signal. Financial analysis of several pilot projects determined that there would need to be between four and six homes per transformer to deliver broadband service at prices equivalent to DSL or cable modem service.
Dial-up connections are not typically considered broadband Internet; however, in some locations, dial-up Internet access is the only available connection technology. Dial-up is less expensive than other broadband offerings and it may be adequate for some uses (i.e., text only email), but may not support other uses like gaming, watching videos, etc. because of inadequate bandwidth.
T1 (or T3) lines are reserved circuits that are usually leased or rented from a company for telecommunications. These lines operate over copper or fiber cables and are used mainly by businesses to connect offices that are geographically separated with voice and data communications. Leased lines are expensive and rarely used for residential purposes.
Source: Information from Wisconsin’s Broadband Reference Guide produced by: WI Public Service Commission, UW-Extension Madison, and the Center for Community Technology Solutions, January 2014