Types of Internet Connections

As technology grows, so does our requirement for greater, better and speedier Internet connections. Throughout the years the way content is displayed by means of the Web has additionally changed radically. Ten years back having the capacity to show striking messages in diverse colors on a page was something to respect. Today, Flash, animations, internet gaming, video streaming, database-driven sites, e-trade are the norm. Hence following are the different Internet Connection Types as indicated by the diverse data bandwidth necessities: 

1. Dial-Up Connections 
2. Cable Connections
3. DSL Connections
4. Leased Line Connections
5. Optical Carrier Connections
6. Internet over Satellite Connections

Let us now discuss each of them in detail.

Dial-Up Connections

Status: OBSOLETE

Mode of Functioning: They are the slowest and the most inexpensive type of Internet Connections available from ISPs. A dial-up connection allows you to connect to the Internet via a local server using a standard 56k modem. Your PC literally dials a phone number provided by your ISP and connects to the server and therefore the Internet.

Advantages: Dial-up connections can be very economic as these connections use a standard 56k modem which most modern laptops have built-in. The fact that you only need a standard phone line to connect makes dial-up connections great when you are on the move, especially if you find yourself in a location without a WIFI connection point.

Disadvantages: Dial-up connections are very slow compared to other connection types. When connected to the Internet the same phone line cannot be used for phone calls. Also Dial-up connections transfer data over an analogue line so before the data is sent it has to be converted from digital to analogue, likewise when data is received it has to be converted from analogue to digital. This adds a performance overhead which affects the speed of the connection.

Cable Connections

Status: Still exist, in very few parts of the world.

Mode of Functioning: Cable Internet access requires a cable modem at the customer's premises and a cable modem termination system at a cable operator facility. The two are connected via coaxial cable. Cable Internet systems can typically operate where the distance between the modem and the termination system is up to 160 kilometers. Downstream Bit rates can be between 400 Mbit/s to 250 Mbit/s. While Upstream Bit rates range from 384 kbit/s to more than 20 Mbit/s.

Advantages: Cable Internet Connections offer much higher speeds than Dial-up Connections. Cable connections transfer data digitally, eliminating any digital/analogue conversion overhead. Cable connections are Always on, eliminating long waits to make a connection and start surfing the web. Also since they don’t transfer data using telephone lines, they don’t affect your ability to make calls when connecting to the Internet.

Disadvantages: Because cable connections are Always on you will need a firewall to protect your PC. 

DSL Internet Connections

Status: The widest form of Internet Connection Type currently in use.

Mode of Functioning: Digital subscriber line (DSL) provides Internet access by transmitting digital data over the wires of a local telephone network. DSL service is delivered simultaneously with wired telephone service on the same telephone line. This is possible because DSL uses higher frequency bands for data. The bit rate of consumer DSL services typically ranges from 256 kbit/s to over 100 Mbit/s (downstream). In ADSL, the data throughput in the upstream direction, (the direction to the service provider) is lower, hence the designation of asymmetric service. In symmetric digital subscriber line (SDSL) services, the downstream and upstream data rates are equal. Asymmetric digital subscriber line (ADSL) is the most commonly installed DSL technology.

Advantages: DSL technology eliminates the need for a second phone line by allowing voice and data transfer at the same time. Because ADSL transfers data digitally it eliminates the usual performance overhead associated with standard dial-up connections. ADSL connections are Always on, which makes the usual long wait to connect a thing of the past.

Disadvantages: The hardware costs can be quite significant as you will need a special ADSL modem and ADSL filters to use the service. Most ISPs allow you to hire these items which can reduce the initial cost. Because ADSL connections are Always on you will need a firewall to protect your PC.

Leased Line Connections

Status: In contemporary use.

Mode of Functioning: A leased line connects two locations for private voice and/or data telecommunication service. Not a dedicated cable, a leased line is actually a reserved circuit between two points. 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." The fastest leased lines are called T3 dedicated lines supporting data rates of about 43 to 45 Mbps. T3 lines are used mainly by Internet Service Providers (ISPs) connecting to the Internet backbone and for the backbone itself.

Advantages: Leased lines most commonly are rented by businesses to connect branch offices, because these lines guarantee bandwidth for network traffic. So-called T1 leased lines are common and offer the same data rate as symmetric DSL (1.544 Mbps).

Disadvantages: Individuals can theoretically also rent leased lines for high-speed Internet access, but their high cost (often more than $1000 USD per month) deters most. Fractional T1 lines, starting at 128 Kbps, reduce this cost somewhat and can be found in some apartment buildings and hotels.

Optical Carrier Connections

Status: In contemporary use.

Mode of Functioning: Optical Carrier (OC) lines, typically used by telecom companies and large enterprises, provide a solid solution for businesses looking for a robust high-powered connection. They are also used by large enterprise businesses to connect to the Internet and to transmit data between offices. The “n” in OC-n can be 1, 3, 12, 24, 48, 192, or 768, and would be multiplied by 51.84Mbps to calculate the actual bandwidth of the circuit. These circuits are delivered via SONET (Synchronous Optical Network) over optical fiber.

Advantages: OC-n is typically used by enterprise businesses for the following:

1. OC service is a great product for Business Class VoIP
2. More than capable of support your Business Email needs
3. Run any E-Commerce platform over OC
4. OC has plenty of bandwidth for supporting Software-as-a-Service
5. Great for General Internet browsing, researching potential clients
6. Supports any type of Web Conferencing applications
7. Great for Disaster Recovery and Business Continuity
8. Plenty of bandwidth for Data Center Applications
9. Great for connecting offices.

Disadvantages: Only big Corporation Data Centers can finance such expensive Internet connectivity lines. It is well beyond the reach of an individual and due to their huge costs, their uses are limited to highly specific uses. An example of the cost overheads involved are that currently, Cisco CRS-1 System features OC-768 line cards. These cards are priced at $2,000,000 USD each.

Internet over Satellite Connections

Status: In Contemporary use.

Mode of Functioning: Satellite Internet access is Internet access provided through communications satellites. Modern satellite Internet service is typically provided to users through geostationary satellites that can offer high data speeds, with newer satellites achieving downstream data speeds up to 15 Mbps.

Advantages: Satellite Internet service provides fixed, portable, and mobile Internet access. It is the only choice available in remote areas. One obvious advantage of getting satellite Internet is the availability of a constant internet connection. Satellite Internet is easy to access and available across several remote regions like includes mountainous regions and other distant areas that cables cannot access; it’s impossible to run miles of cable through rough areas after all.

Disadvantages: Satellite communication typically requires a clear line of sight, will not work well through trees and other vegetation, is adversely affected by moisture, rain, and snow (known as rain fade), and may require a fairly large, carefully aimed, directional antenna. It is among the most expensive forms of broadband Internet access.

To further your knowledge, I'd advise you to read about Types of Network Connections. Take care :)