When you connect to the Internet, you might connect through a regular modem (dial-up), through a local-area network (LAN) connection in your office, through a cable modem (Cable Internet) or through a Digital Subscriber Line (DSL) connection.
For me DSL connection is the most cost-effective solution that home based and small business office can leverage to grow a business. It is not only widely available but its reliability and high-speed capability is what it makes one of the most preferred access service.
DSL is a broadband high-speed connection that uses the same wires (2-wire) as a regular telephone line. Simultaneous use of voice and data (internet) one can log on to the internet while also using the line to make voice calls. The speed connection is much higher than a regular modem which can hit to a max of 56Kbps only. DSL can use existing phone line or delivered as stand-alone DSL connection. The company that offers DSL will usually provide the modem as part of the installation.
A drawback with DSL is that a DSL connection works better when you are closer to the provider’s central office. The connection is faster for receiving data than it is for sending data over the Internet. The service is not available everywhere again owing to distance limitation.
All types of DSL service fall into one of two basic categories: symmetric and asymmetric. Symmetric types of DSL support the same bandwidth between the subscriber and the service provider in both directions.
Asymmetric types of DSL or ADSL support relatively more bandwidth in the downstream direction (from the service provider to the subscriber) and less bandwidth in the upstream (from the subscriber to the service provider). ADSL is popular among Internet Service Providers (ISP).
ADSL uses two pieces of equipment, one on the customer end and one at the Internet service provider which is usually telephone company or other provider of DSL services. At the customer’s location there is a DSL transceiver also called Customer-Premise Equipment or CPE, which may also provide other services. The DSL service provider has a DSL Access Multiplexer (DSLAM) to receive customer connections.
A DSL Modem or CPE is like transceiver equipment, it transmit and receive data packets (information) over ordinary telephone cable. This data packets are actually digital signals but since digital signal cannot travel far, the DSLAM from the ISP’s head end transform the signal from digital to analog signal for transmission over an analog channel (two-wire telephone cable) usually at a distance of up to 5Km from central office and the DSL Modem or CPE converts the signal back to digital. The DSL Modem is the equipment where data from the user’s computer or network is connected to the DSL line. DSL Modem can connect to a customer’s equipment in several ways, though most residential installation uses USB or 10 base-T Ethernet connections (RJ-45).
The DSLAM at the service provider is the equipment that really allows DSL to happen. A DSLAM is the point-of-contact where a dedicated, high-speed link to the internet called backhaul connection is terminated. An E1 (2048Kbps) or T1 (1536Kbps) Dedicated Internet is an example of a backhaul internet link that can be use to service between 80-100 DSL subscribers. DSL technology is the reason why internet connection is becoming cheaper by the days. It is able to share or distributed for greater use a dedicated connection (backhaul) to several subscribers while maintaining quality of service. Cost-of-service is significantly lowered.
The DSLAM takes connections from many DSL subscribers and aggregates them onto a single, high-capacity connection to the Internet. DSLAMs are flexible and able to support multiple types of DSL in a single central office, and different varieties of protocol and modulation. In addition, the DSLAM may provide additional functions including routing or dynamic IP address assignment for the customers.
ADSL is a distance-sensitive technology: as cable connection’s length increases, the signal quality decreases and the connection speed goes down. Connection is much more stable the nearer the user is to the central office. With a maximum 18,000 Feet (5,640 meters) effective service length, some ADSL providers generally limit distance it serves to a max of 3.5Km. Beyond this some subscribers enjoy speeds below the promised maximums.
Bursting and Committed Information Rate (CIR) are two factors to consider in choosing a DSL service. Remember, DSL is a shared internet connection service depending on the port configuration or package variation of the service providers. Bursting is the term use to describe a service which does not guarantee a certain speed. Connection bandwidth may vary from maximum of the port-speed subscribed (as provided by the ISP) to a minimum of as much as 32Kbps. DSL that offers Committed Information Rate (CIR) or minimum guaranteed speed is much more desirable for it assures a sure connection to the international internet gateway.
In choosing an ADSL package fit for your home-based or small business requirements, try to ask the ISP of the recommended count of users and type of application that the DSL package can support. Usually, residential package can support only up to 1 or 2 PC. However, with competition and greater availability of other broadband internet access, ADSL packages currently being offered by ISPs can support all type voice, data and video applications and at greater speed.