What Is a Leased Line in Networking?

A leased line, also known as a dedicated line, connects two locations for private voice and/or data telecommunication service. A leased line is not a dedicated cable; a leased line is actually a reserved circuit between two points.

Leased lines can span short or long distances. They maintain a single open circuit at all times, as opposed to traditional telephone services that reuse the same lines for many different conversations through a process called “switching.”

What Are Leased Lines Used For?

Leased lines are most commonly rented by businesses to connect branch offices of the organization. Leased lines guarantee bandwidth for network traffic between locations. For example, T1 leased lines are common and offer the same data rate as symmetric DSL (1.544 Mbps).

Individuals can theoretically also rent leased lines for high-speed Internet access, but their high cost deters most, and there are far more affordable home options available higher bandwidth than a simple dial-up phone line, including residential DSL and cable internet broadband service.

Fractional T1 lines, starting at 128 Kbps, reduce this cost somewhat and can be found in some apartment buildings and hotels.

Virtual Private Networks (VPNs) are an alternative technology to leased lines, allowing an organization to create a virtual and secure connection between locations, and even between locations and remote clients like employees.

Broadband Internet Services

For consumers looking for internet access, a leased line is generally not a feasible option. There are fast broadband internet connections available that are much more affordable.

Access to these broadband services varies depending on location. Generally, the further from a populated area you live, the fewer broadband options will be available.

Broadband options commonly available to consumers include:

  • Digital Subscriber Lines (DSL): DSL service uses existing telephone wiring to deliver broadband service. Voice telephone service does not use all of the broadband capacity of the telephone system’s copper twisted pair of wires, and DSL utilizes that free space.
  • Cable modems: Cable service represents another pre-existing wire into many homes. The coaxial cable is used to carry the additional broadband internet signal.
  • Wireless broadband: Wireless broadband uses a radio link between the user’s location and the service provider’s facility. Range is limited, making availability more limited as well.
  • Wireless cell phone internet: Broadband service is often available using 3G and 4G cellular signals that are commonly used by smartphones. Though not as fast as DSL or cable and it can be expensive if you have high data usage, it is a faster option than dial-up for rural customers.
  • Satellite broadband: Satellite broadband service may be the only broadband service available in rural areas. The service often accompanies satellite television service and uses the same receiver for downloading. Speed, however, is not as fast as other services, but it is much faster than dial-up service.

WiMax vs. LTE for Mobile Broadband

Question: WiMax or LTE for Mobile Broadband?

WiMax and LTE are the two emerging technologies for high-speed mobile broadband Internet service. Both WiMax and LTE appear to have similar goals for enabling worldwide wireless data network connectivity for cell phones, laptops, and other computing devices. Why then do these two technologies continue to compete with each other, and what are the differences between WiMax and LTE?

Answer: Different wireless providers and industry vendors back either WiMax or LTE, or both, depending on how these technologies benefit their businesses. In the U.S., for example, cellular provider Sprint backs WiMax while its competitors Verizon and AT&T supports LTE. Manufacturing companies may prefer one or the other depending on their ability to produce hardware more or less expensively.

Neither technology is expected to replace Wi-Fi home networks and hotspots. For consumers, then, the choice between LTE and WiMax comes down to which services are available in their region and offer better speed and reliability.​
Availability

Cellular network providers like Verizon in the U.S. intend to roll out Long Term Evolution (LTE) technology as an upgrade to their existing networks. Providers have installed and began testing some LTE equipment in trial deployments, but these networks are not yet open to the public.

Estimates for when the first LTE networks will be available range from later in 2010 to sometime in 2011.

WiMax, on the other hand, is already available in some locations. WiMax makes sense especially in areas where 3G cellular service is not currently available. However, the initial deployments done for WiMax have been concentrated in densely populated areas like Portland (Oregon, USA), Las Vegas (Nevada, USA) and Korea where other high-speed Internet options like fiber, cable, and DSL already exist.
Speed

Both WiMax and LTE promise higher speed and capacity compared to earlier 3G and wireless broadband network standards. Mobile Internet service can theoretically reach between 10 and 50 Mbps connection speeds. Do not expect to see such speeds regularly until these technologies mature over the next several years. Existing customers of the Clearwire WiMax service in the U.S., for example, generally report speeds below 10 Mbps that fluctuate depending on location, time of day and other factors.

Of course, as with other types of Internet service, the actual speed of connections depends on the type of subscription chosen as well as the quality of the service provider.
Wireless Spectrum

WiMax has not defined any one fixed band for its wireless signaling. Outside the U.S., WiMax products have conventionally targeted 3.5 GHz as that is an emerging standard for mobile broadband technologies generally. In the U.S., however, the 3.5 GHz band is mostly reserved for use by the government. WiMax products in the U.S. have typically utilized 2.5 GHz instead although various other ranges are also available. LTE providers in the U.S. intend to use a few different bands including 700 MHz (0.7 GHz).

Using higher signaling frequencies allows a wireless network to theoretically carry more data and thus potentially provide higher bandwidth.

However, higher frequencies also tend to travel shorter distances (affecting the coverage area) and are more susceptible to wireless interference.

Use and Misuse of the Word Broadband in Networking

The term broadband technically refers to any type of signal transmission technique that carries two (or more) different types of data in separate channels over a common wire, either wired or wireless. In popular usage, it refers to any sufficiently high-speed Internet connection.
Definitions of Broadband

As old dial-up network connections to the Internet began to be replaced with newer, higher speed alternatives, all of these newer technologies were typically marketed as “broadband Internet.” Government and industry groups have attempted to set official definitions for what distinguishes broadband services from non-broadband, primarily based on the maximum data rates they supported.

These definitions have varied over time and also by country. For example:

in the Philippines, download data rates of 256 Kbps qualify as broadband (as of 2016)
in India, the official broadband speed threshold was raised from 256 Kbps to 512 Kbps downloads in 2014.
in the U.S. the Federal Communications Commission (FCC) raised its broadband rate limit in 2015 from 4 Mbps to 25 Mbps for downloads (and from 1 Mbps to 3 Mbps for uploads). Originally, back in 1999, the FCC set its broadband threshold at 200 Kbps for downloads.

Types of Broadband Network Technologies

Among the Internet access technologies routinely classified as “broadband” are

Digital Subscriber Line (DSL) – Internet service that combines separate voice and data channels over a single telephone line. In DSL, voice traffic fills the low end of the frequency spectrum and data fills the high end.
Cable modem – Internet service combining high-speed data with video signals supplied over cable TV lines.

Mobile broadband – Internet data connections made through smartphones and other mobile devices to cellular networks
Fiber Internet (FTTH) and fixed wireless broadband – types of Internet service that qualify as broadband Internet under popular definition even though these technologies carry only a single type of data traffic (dedicated to Internet connectivity)

Broadband home networks share access to a broadband Internet connection through local network technologies like Wi-Fi and Ethernet. Although both operate at high speeds, neither of these are considered “broadband.”
Issues with Broadband

People living in less populated or underdeveloped areas tend to suffer from lack of access to broadband Internet services as providers have less financial motivation to service areas with relatively fewer potential customers. So-called municipal broadband networks that offer government supported Internet service to residents have been built in some areas, but these have limited reach and have reportedly caused tensions with privately-owned service provider businesses.

Building large-scale broadband Internet access networks can be very expensive due to the extensive infrastructure and industry regulation involved. High infrastructure costs make it difficult for service providers to lower the prices of their subscriptions and reliably offer customers the connection speeds they want. In the worst case, a household can be charged high additional fees for exceeding their monthly data plan allowance, or have their service temporarily restricted.